Laboratory Safety and Chemical Hygiene Plan

A sustainable safety culture in research is built on leadership engagement, hazard awareness, enhanced communication, and behavior changes. The Laboratory Safety and Chemical Hygiene Plan provides information and guidance to help conduct laboratory work safely and in compliance with environmental health and safety regulations and University policy. It is also a useful training resource for principal investigators, other supervisory personnel, safety designates, and laboratory members. While it primarily addresses work in laboratory spaces, much of the information is applicable to non-laboratory spaces where hazardous chemicals or processes are used.

The Laboratory Safety and Chemical Hygiene Plan is required by the Occupational Safety and Health Administration (OSHA) Laboratory Standard 29 CFR 1910. 1450. The Lumen Profile is the laboratory-specific portion of the chemical hygiene plan. Lumen Profiles are required for all research, research-support, and teaching laboratory spaces.

Although the information in this document is compiled from sources believed to be reliable, it is not all-encompassing and is intended only to serve as a starting point for good laboratory practice. The laboratory manager or supervisor is responsible for laboratory-specific information, for developing and maintaining a safe workplace, and for complying with federal, state, and local laws and University policy.

Whenever used, the word shall indicates required procedures. The word should indicates a recommendation for good practice.

Policies and procedures for work with radioactive materials are administered by the Radiation Safety Committee in the  Radiation Safety Handbook. The Laser Safety Handbook covers policies and procedures for work with lasers. Policies and procedures for work with potentially infectious agents and recombinant DNA are covered in the Institutional Biological Safety Manual, which references the CDC Biosafety in Microbiological and Biomedical Laboratories, 5th Ed. and the OSHA Bloodborne Pathogen Program.

This document has been reviewed by the Laboratory and Chemical Safety Committee and approved by the Vice President for Research.

1.1 Federal Laws and Regulations

There are a number of federal, state, and local laws, regulations, ordinances and standards that pertain to laboratory activities and conditions that affect the environment, health and safety. International regulations apply to air and marine transport of laboratory materials. Safety standards and codes are created by nongovernmental bodies, but are important to know because they may be required by a law (by reference), as condition of occupancy, by an insurance company, by an accrediting body, or as a p. 7 widely accepted industry standard. In some cases, following a safety guideline is a condition of receiving a research grant¹.

There are a number of guideline setting governmental and non-governmental agencies. The main guideline for chemical and laboratory safety is the National Research Council’s Prudent Practices in the Laboratory 2011, which is referenced throughout this document.

Other notable agencies include the National Fire Protection Agency (NFPA), the National Institute for Occupational Safety and Health (NIOSH), National Institutes of Health (NIH), the National Toxicology Program (NTP), the Compressed Gas Association (CGA), the American Conference of Governmental Industrial Hygienists (ACGIH), the American Chemical Society (ACS), the American Industrial Hygiene Association (AIHA) , the American Institute of Chemical Engineers (AIChE) and other standard developing agencies under the American National Standards Institute (ANSI).

Table 1.1

Federal Safety Laws and Regulations That Pertain to Laboratories – Regulations of Chemical, Physical and Mechanical Hazards in Laboratories².

Table 1.2

Federal Safety Laws and Regulations That Pertain to Laboratories – Environmental Regulations

Table 1.3

Federal Safety Laws and Regulations That Pertain to Laboratories – Shipping, Export, and Import of Laboratory Materials

Table 1.4

Federal Safety Laws and Regulations That Pertain to Laboratories – Regulation of Laboratory Injuries, Accidents, and Spills

Table 1.5

Federal Safety Laws and Regulations That Pertain to Laboratories – Other regulations

1.2 Local Laws

• City of Evanston Recovery of Hazardous Substance Removal and Abatement Costs Ordinance: provides for recovery of emergency response costs.
• City of Chicago Liability for Fire Suppression and Other Emergency Costs Ordinance: provides for recovery of emergency response costs.
• The Metropolitan Water Reclamation District of Greater Chicago Sewage and Waste Control Ordinance.

1.3 Regulation of Laboratory Design and Construction

Laboratory design, construction, and renovation are regulated mainly by state and local laws that incorporate, by reference, generally accepted standard practices, such as the International Building Code (IBC) 2012, the International Fire Code (IFC) 2012 in Evanston, and the National Fire Protection Association (NFPA) standards and the City of Chicago Building Code in Chicago. For laboratory buildings where hazardous chemicals are stored or used, detailed requirements usually cover spill control, drainage, containment, ventilation, emergency power, special controls for hazardous gases, fire prevention, building height, and allowable quantities.

In addition, OSHA standards affect some key laboratory design and construction issues, for example eyewashes, safety showers, and special ventilation requirements. Other consensus standards prepared by organizations such as the American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) are relevant to laboratory space design. It is common for various codes and consensus standards to be incorporated into state or federal regulations.

This section describes and assigns those responsibilities that deal directly with laboratories using chemicals, biological materials, radioactive materials, other sources of ionizing radiation, and/or lasers.

All faculty, staff, and students are required to complete mandatory training assigned through Lumen based on their hazard and risk profile.  For some training, this is an annual requirement.  For other training, it only needs to be completed once.

2.1 Vice President for Research

The President of the University has delegated administrative responsibility for the chemical, biological, radiation, and laser safety programs to the Vice President for Research.

2.2 Department Heads, Center Directors, and Other Facility Directors

The term department head will be used in this text to include center directors and other facility directors.

Department heads should coordinate with Northwestern Environmental Health and Safety to develop evacuation plans for buildings, appoint building safety committees, and appoint building safety managers and alternates.

The department head shall maintain discipline, enforce rules and regulations, and take prompt, effective corrective action when necessary. The department head shall also provide assistance to Research Safety staff when situations arise involving PIs and other personnel in the department.

The department head shall be familiar with and understand the federal, state, and local regulations and University policies applicable to the department’s work and shall ensure compliance through PIs and other supervisory personnel.

The department head may delegate safety and health-related responsibilities to PIs or other supervisors, but it is the department head’s responsibility to see that the requirements are met.

The department head is responsible for ensuring that engineering controls and safety equipment are inspected and maintained according to the required maintenance schedule. The department head shall ensure that the PIs institute medical surveillance programs for personnel with occupational exposure to certain agents.

When a PI vacates a laboratory space, the department head is responsible for ensuring that the lab space is properly cleaned out and prepared for the next occupant. The department head shall be responsible for providing decontamination of the lab space if the PI fails to do so.

2.3 Principal Investigators and Shared and Core Facilities Managers

The term principal investigator (PI) as used in this document shall include laboratory and other supervisors (such as managers or directors of shared and core facilities). A PI is defined as any faculty member who has been granted permission by the Office for Sponsored Research to serve as a PI on a project or to submit a proposal. All persons granted faculty-level research appointments are eligible to be PIs. The Vice President for Research may authorize others to be PIs or core facility managers for the Office for Research.

The PI is responsible to the department head for the safe and legal conduct of research under his or her purview. Shared or core facility managers are responsible to the faculty director and the respective administration. This safety responsibility shall not be delegated. The PI shall be aware of the physical and health hazards associated with all materials present in the laboratory space. The PI shall record all acquisitions of Chemicals of Interest within 30 days.

The supervisor of a teaching laboratory is also considered a PI in the context of the Research Management Platform Lumen. The supervisor of a teaching laboratory does not need to register students in Lumen who participate in laboratory activities as part of a Northwestern University class. Laboratory teaching assistants are required to be registered as laboratory workers in Lumen.

In the event of an incident including infectious exposure, the PI shall initiate appropriate emergency procedures, follow the incident reporting requirements and formulate a temporary laboratory shutdown plan.

The PI shall add all supervised laboratory members to their Lumen Profile, make all laboratory members aware of the profile, and enforce the safety rules and procedures described therein. The PI shall be familiar with and understand the rules, regulations, and University policies pertaining to the workplace. These encompass but are not limited to the following items: standard operating procedures, training, record keeping, maintaining and providing easy access to SDSs, labeling chemicals, labeling and proper disposal of surplus and waste materials, posting warnings, medical surveillance, inventory reporting, engineering controls, safe work practices, personal protective clothing and equipment, and access restrictions.

The Occupational Safety and Health Administration (OSHA) states that it is “clear that it is the employer’s responsibility to compel compliance… it is the employer, and not the employee, who controls the conditions of work at a given workplace.” According to University interpretation, the PI is defined as the individual responsible for ensuring adherence to safety regulations and proper use of safety equipment in the laboratory space. The PI shall correct any deficiencies that could compromise health and safety or compliance.

The PI shall not assign pregnant women to clean hazardous materials spills or work with chemicals that are particularly hazardous to a fetus.

When closure of a laboratory space becomes imminent, the PI is responsible for following the lab closeout process in the Laboratory Closeout Checklist. The PI ensures removal of all chemical and other health and safety hazards so the laboratory space is safe for renovation or subsequent use. The PI shall report to the department head that all hazardous materials have been removed and work surfaces (lab furniture, refrigerators, freezers, chemical fume hoods, etc.) decontaminated with an appropriate and Research Safety-approved method. Should a PI abandon hazardous material, the department becomes responsible for arranging disposal, both in terms of inventory and funding.

The PI may choose a proxy or Safety Designate to enter information into the Lumen Profile; however, it is the PI/Supervisor responsibility to verify that the data is complete and accurate.

The Safety Designate shall be a senior lab member. It is inappropriate to delegate the Safety Designate role to a junior member of the lab team.

2.4 Laboratory Members

Each individual who works in a laboratory where hazardous materials are used is considered a laboratory member. Each laboratory member shall know and comply with the University’s safety policies and rules and shall follow both oral and written instructions from the PI or supervisor. The individual shall report to the PI any unsafe conditions and any accident or exposure. If the individual receives no response or an unsatisfactory response, (s)he shall contact the department head or Research Safety. The department head or Research Safety shall ensure confidentiality for the individual reporting a safety concern. Northwestern University has selected EthicsPoint to provide a simple way to report activities that may involve misconduct or violations of Northwestern University policy. Laboratory safety concerns may also be submitted directly to Research Safety using the ObservNow function in Lumen.

The individual shall know the hazards in the workplace as well as proper hazardous material handling and disposal procedures. Training shall be provided or arranged by the PI. Avoid working alone in a building; do not work alone in a laboratory if the procedures being conducted are hazardous³.

Research Safety encourages pregnant women to voluntarily declare their pregnancy and receive consultation from an occupational health services provider. Contact Risk Management for a free Clinic Passport and bring a list of hazardous chemicals, infectious materials or radioactive materials you are exposed to in your occupational environment.

If you are pregnant or planning to become pregnant, contact Research Safety so we can provide guidance in minimizing an exposure risk.

2.5 Students

Although the federal and state laws apply only to employees (including student employees), it is the policy of Northwestern University to ensure that all students who might be exposed to hazardous materials in the course of their activities at the University are also adequately protected and trained. Therefore, Lumen Profiles shall also be prepared for teaching laboratories. The laboratory supervisor shall instruct students in the appropriate safety precautions and enforce the given rules.

Working alone is especially dangerous when those involved have little research experience, such as undergraduates or those who have not demonstrated competency working with a new hazard. Working alone in a laboratory is strongly discouraged for many reasons. If something serious happens, you may not be able to self-rescue. Your judgment may be impaired; for example, if you have a major spill or even a minor emergency, fatigue may impede or adversely affect your response.

2.6 High School Students

Proper supervision is the responsibility of the host Principal Investigator.

High school students must be registered through the NU Human Resources volunteer system and must complete the liability waiver required by Risk Management. For access to registry and safety training, unpaid high school students must be assigned a NetID and Person Outside the Institution (POI) number.

Assigned science projects should be commensurate with existing knowledge, skills and abilities. High school students cannot work with potential pathogens, radioactive materials or particularly toxic or reactive chemicals.

High school students must be properly supervised at all times and not allowed unaccompanied access or work in the laboratory.

Appropriate training, dress, lab coat and use of personal protective equipment is expected.

2.7 Research Safety

Research Safety helps faculty, staff, students, and visitors to work safely, to create safe workplaces, and to achieve and maintain compliance related to health, safety, and protection of the environment.

In carrying out this mission, Research Safety performs a basic risk management function in facilitating protection of the University and individual interests against loss from injury, accident, civil or criminal penalties, and litigation.

Research Safety provides information, training, and technical resources to department heads, center directors, and principal investigators to assist them in implementing the chemical, radiation, laser and biological safety programs.

Research Safety’s responsibilities for laboratory safety include:

• Compiling chemical inventory information and submitting reports to federal, state, and local agencies
• Collecting and disposing of waste and surplus chemicals
• Surveying laboratory facilities and offering recommendations for improved practice
• Maintaining records of laboratory facilities in Lumen
• Coordinating the registration programs required by the Institutional Biosafety Committee and the Radiation Safety Committee
• Providing 24-hour emergency response to spills or other accidents and investigating incidents involving hazardous materials
• Advising University personnel in safe work practices, personal protective clothing and equipment, engineering controls, and regulatory requirements
• Conducting or arranging for environmental monitoring
• Inspecting chemical fume hoods and other engineering controls
• Recommending policies and procedures for the safe conduct of work with chemicals 

Research Safety representatives are authorized to enter University facilities within their jurisdiction at any time to observe working conditions, monitor equipment, and sample for contaminants. The director and the chemical hygiene officer are authorized to close a facility or stop a process or procedure that poses an imminent danger to life or property.

2.8 Committees

2.8.1 Laboratory and Chemical Safety Committee

A Laboratory and Chemical Safety Committee may convene ad hoc for cause. Members are drawn from each campus and a variety of disciplines, including chemistry, engineering, and biomedical sciences respectively. They are appointed by the vice president for research.

The committee’s responsibilities do not include research involving ionizing and non-ionizing radiation, recombinant DNA molecules, human blood, or pathogenic microorganisms. Such activities are under the jurisdictions of the Radiation Safety Committee, the Laser Safety Committee and the Institutional Biosafety Committee. Research involving animals is under the jurisdiction of the Institutional Animal Care and Use Committee. 

The general purposes of the committee are to:

• Formulate and recommend to the vice president for research policies governing the use of chemical carcinogens and other chemicals in the laboratory
• Monitor the compliance of the University with respect to federal, state, and local regulations pertaining to hazardous materials in the laboratory

The Committee has a number of specific responsibilities, including:

• Recommending policies and procedures for a chemical safety program, including, but not limited to, educational programs, laboratory inspections, containment requirements, waste disposal programs, and medical surveillance
• Reviewing incident reports

2.8.2 Institutional Biosafety Committee (IBC)

All regulatory and safety issues related to the use of recombinant DNA, human blood, select agents, pathogenic microorganisms and biosafety level 3 laboratories are governed by the Institutional Biosafety Committee.

2.8.3 Radiation Safety Committee

All regulatory and safety issues related to the use of radioactive materials and X-ray are governed by the Radiation Safety Committee.

2.8.4 Laser Safety Committee

All regulatory and safety issues related to the use of Class 3b and 4 lasers are governed by the Laser Safety Committee. For licensing requirements, policies, and procedures see the Laser Safety Handbook.

In University buildings, always call 911 if there is an explosion, fire, injury, or spill-related evacuation. If calling from a cell phone, report the incident’s building address, which is posted in each laboratory.

If applicable, know the appropriate emergency procedures for non-University locations. Call for assistance when needed. If there is a chemical, radioactive or biological material spill beyond the laboratory member’s ability to safely contain or clean up, call University Police at 456 at any time, and that office will contact Research Safety. During business hours, you may call Research Safety directly at 3-8300 (Chicago) or 1-5581 (Evanston).

During Human Resources’ new employee orientation, each new University employee receives basic safety instructions through the Employee Safety Handbook . 

3.1 University Emergency Response Plan

The University Police maintains the University’s Emergency Response Framework for emergencies. The Emergency Response Framework formalizes responses to all classes of emergencies, from small events to catastrophes. In emergency situations, the role of UP is to investigate the situation, provide site security, implement the emergency plan, and establish communications. Research Safety will advise and assist with hazardous-material spill control and cleanup. When the ability to respond adequately to an emergency is beyond the capability of the University personnel, UP will call the local fire department or local hazardous materials response team. Research Safety may direct UP to make this call.

3.2 Building Emergency and Evacuation Plans

The University Emergency Response Framework requires that department heads cooperate to establish building safety committees and appoint building safety managers and alternates. The building safety committees develop evacuation plans for each building. The plans include a telephone tree for notifying key persons in case of emergency. All building occupants receive training in their respective evacuation plan. Safety wardens are appointed for each building.

In the event of a fire, hazardous material release, or other hazardous situation requiring emergency response in a safety warden’s zone, the warden will:

• Activate the fire alarm, if needed
• Call University Police and report the incident
• Notify occupants to evacuate the zone
• Assist emergency personnel by providing information regarding location of the incident, origin, and persons involved

The senior officials of Research Safety, University Police, Risk Management, and Facilities are authorized to initiate evacuation of buildings.

3.3 Loss of Power⁴

Most laboratory buildings experience occasional brief periods of power loss. Such instances may be minor disturbances or could damage equipment or ruin experimentation. Longer term power outages may cause significant disruption and loss. It is prudent to consider the effects of long-term and short term power loss and implement plans to minimize negative outcomes.

3.3.1 Short-Term Power Loss

Consider what can happen in the event of short-term power loss. If the outcome is more than just an inconvenience, implement steps to reduce the impact. For example, if temperature is regulated by a heating mantle and loss of heat for even a few minutes could create an unacceptable variation, the result may be loss of that particular experimental run.

When developing a plan for handling a short-term power loss, consideration should be given as to what state a piece of equipment goes to during a loss of power or a resumption of power. Equipment should enter a fail-safe state and it should be tested for this state by purposely shutting off power to it and then reenergizing the circuit. Any interlocks (e.g., against high temperatures on heating mantles) should be rechecked after a loss of power. Some equipment must be restarted manually after a shutdown, resulting in longer term power loss even when power is restored. Uninterruptable power supplies and automatic generators should be considered for freezers and refrigerators that are used to store unstable compounds.

Laboratory Procedures

If laboratory personnel are present when power is lost, and power is not restored immediately, consider the following actions:

• Turn off equipment, particularly if leaving before power is restored. Some equipment can be damaged if turned on abruptly once power comes back online. If no one is in the laboratory when the power is restored, equipment that does turn on will be running unattended.
• Discontinue operations requiring local ventilation, such as laboratory chemical hoods. The building ventilation system may not be on emergency power.
• Close laboratory chemical hood sashes.

3.3.2 Long-Term Power Loss

Damaged power distribution systems and other conditions may result in power loss that lasts hours or days. This has implications for security, safety, and experimental work that go well beyond those for a short-term power loss.

Security Issues

For laboratory spaces with specialized security systems, such as card readers or electronic locks, know if the locks are locked or unlocked in the event of power failure. Develop a backup plan for laboratory security in the absence of such systems.

Environmental and Storage Conditions

The most common problem during a power outage is storage of materials that require specialized environmental conditions, such as refrigeration and humidity controls. For example, sub-80 C freezers, may hold their temperature for a few hours after a power loss but will eventually warm. This warming may lead to loss of samples or, for materials that become unstable when warmed, to more hazardous conditions, including fire, over pressurization, or release.

Discontinuation of Experiments

Experiments that rely on power may need to be discontinued and disassembled. Leaving the materials in place may not be prudent. Assign responsibility to identify problems and ensure that materials are safely stored.

Preplanning

There are many options for minimizing the effects of a power loss, including alternative energy sources and, when that is not practical, prioritizing experimental needs, consolidating, and using dry ice. Do not depend on safety showers or eyewashes. This safety equipment relies on a booster pump that may not be operational. Emergency telephones and manual pullbox stations should continue to operate properly. Be prepared by keeping flashlights in the work area.

Generator Power

A laboratory building may be connected to an emergency generator. If so, know what circuits or outlets are supported by emergency power. In some buildings, for example, the generator may only run emergency lighting and security systems. In others, power for the ventilation system, all or in part, may be backed up by the generator. Some buildings may have specially marked outlets that are connected to the generator. One potentially negative aspect of a generator is that there is usually a slight delay, up to several seconds, from the time the power is lost to the time that the power load is taken up by the generator. Equipment that is sensitive to a minor power disruption may be affected and a generator may not provide power without an interruption.

Know what will continue to operate during a power loss. Determine how long the laboratory operation can rely on the generator. If there is equipment that would benefit from generator backup, inquire about the making of such a connection.

Uninterruptible Power Supply (UPS)

When generator power is not available or if equipment is sensitive to the slight power delay, UPS systems may be the right choice for continued power. UPS systems are composed of large rechargeable batteries that immediately provide emergency power when the main supply is interrupted. UPS systems come in a variety of types and sizes. The three basic types are offline, line interactive, and online. The differences among the three are related to the level and type of surge protection, with the offline providing the least amount of surge protection and the online providing the most sophisticated protection. Size varies based on power needs. When purchasing an UPS for equipment other than a computer, consult with the equipment manufacturer to help choose the right solution. All UPS systems require some degree of maintenance. The battery needs to be replaced at an interval specified by the manufacturer. Batteries may be expensive and should be figured into the cost of the system.

3.4 Floods⁵

Floods could be due to rain, water pipe breaks, or accidental or deliberate acts. Some areas are more prone to flooding than others. Laboratory spaces on the basement or ground level are more likely to be flooded in a storm than those on higher floors. Safety showers and eyewash stations that are not properly plumbed or do not have floor drains nearby may also be a source of flooding. Consider the likelihood of flooding and its impact. Also consider whether the laboratory space contains equipment that is very sensitive to water damage. If flooding occurs, could it affect the space below the flood? If so, is the floor sealed appropriately? Are there overhead pipes?

 To avoid flooding, do not block the sink drains. Place rubber matting in the bottom of the sinks to prevent breakage of glassware and to avoid injuries. While the use of water as a coolant in laboratory condensers and other equipment remains common practice, there are alternative means for example a FindenserTM. Many flooding incidents occur when the tubing supplying the water to the condenser disconnects. Hoses can pop off when building water pressure fluctuates, causing irregular flows, or can break when the hose material has deteriorated from long-term or improper use. Floods also result when exit hose jump out of the sink from a strong flow pulse or sink drains are blocked by an accumulation of extraneous material. Proper use of hose clamps and maintenance of the entire cooling system or alternative use of a portable cooling bath with suction feed can resolve such problems.

3.5 Incident (Accident) Reporting

Laboratory incidents shall be investigated. The PI shall submit an Incident Report Form to Research Safety in case of injury, minor spills, fires, or hazardous material release. In the event of a work related injury the PI follows the Occupational Health protocol for the respective campus: Lab Injury Protocol – Evanston or Lab Injury Protocol – Chicago and fill out a Supervisor’s Injury or Illness Investigation Report .

Research Safety may ask for safety committee assistance to investigate and prepare an investigation report. Investigations are made and reports written not only to satisfy certain laws but more importantly to learn the cause of the problem and what changes in procedures, equipment, or training should be made to avoid other accidents.

All lost time claims shall be reported to Occupational Health. Work related injuries are entered in the OSHA Injury Log. In case of a fire, injury, or other accident requiring outside assistance, the Safety and Loss Prevention Division may write an investigation report.

3.5.1 Research Safety Assistance

Research Safety will respond to chemical, radioactive and biological materials spills. However, if the spilled material is not volatile and there is no immediate fire or toxic hazard, cleanup may be done by laboratory members (under direction of the PI or Research Safety). Research Safety will provide cleanup supplies and equipment, and cleanup instructions. In situations involving a fire of research chemicals or toxic hazards, Research Safety will advise on evacuation or other precautions to protect persons or property in the immediate area.

3.6 Personal Injury

At least two members of each lab group should receive first aid and CPR training. PIs/supervisors must determine whether to arrange for and/or sponsor first aid and CPR training for their staffs. In the event of a work related injury follow the Occupational Health protocol for the respective campus: Lab Injury Protocol – Evanston or Lab Injury Protocol – Chicago.

3.6.1 Burn from Fire

• If your clothing catches fire, immediately get under a safety shower or other water source.
• Assess the condition of the skin’s burn area. If skin is not broken, run water over the burn area to remove heat. Don’t put ice on the burn. If skin is broken, apply a dry, sterile dressing over the wound.
• Seek medical attention as soon as possible.

3.6.2 Inhalation

A person exposed to smoke or fumes shall be removed to fresh air. Any victim overcome by smoke or fumes shall be treated for shock. Call 911. Give cardiopulmonary resuscitation (CPR) if necessary and if trained personnel are available. If a person needs to be rescued from a contaminated area, evaluate the possibility of harm to the rescuer before anyone enters or remains in the contaminated area without proper protective equipment. If a printed SDS is available for the material inhaled, it should accompany the victim to the medical treatment facility.

3.6.3 Shock

Shock is likely to develop in any serious illness or injury. Shock is a condition in which the circulatory system fails to deliver blood to all parts of the body. When the body’s organs do not receive adequate blood supply, they fail to function properly. The following signals are indicators that the victim is suffering from shock:

• Restlessness or irritability (often the first sign that the body is experiencing a significant problem)
• Altered consciousness
• Pale, cool, moist skin
• Rapid breathing
• Rapid pulse

In caring for shock, have the victim lie down. Help the victim rest as comfortably as possible to minimize pain and thereby slow the progression of shock. Control any external bleeding. Help the victim maintain a normal body temperature and avoid chilling. Elevate the victim’s legs about 12 inches unless you suspect broken bones or possible head, neck, or back injuries. If in doubt, leave the patient lying flat.

Do NOT give the victim anything to eat or drink although they may complain of thirst. Obtain medical assistance promptly since shock cannot be managed by first aid alone.

3.6.4 Ingestion

If a person ingests a toxic chemical, determine, if possible, what was ingested and notify the emergency medical personnel. Contact the Poison Control Hotline at (800) 222-1222 for emergency response information for the specific compound.

Inform the hotline personnel of the first aid treatment shown on the container label or the SDS. The printed SDS should accompany the victim to the medical treatment facility.

3.6.5 Puncture or Cut

When treating a victim with a puncture wound or cut, wear personal protective equipment (e.g., gloves) to minimize exposure to human blood, body fluids, or other chemical or biological contamination. Apply a pressure pad or clean cloth firmly to the wound. Raise the wounded area above the level of the heart to slow the bleeding. For severe bleeding or spurting, very firmly press a pressure pad directly on the wound and apply pressure at the applicable body pressure point above the wound to stop the flow of blood. In a severe injury, keep the victim warm, calm, and oriented to prevent shock.

3.6.6 Needlestick

Immediately wash needlesticks or other accidents involving skin punctures by a chemical or biological agent. Appropriate medical testing, treatment, and follow-up may be indicated and shall be provided as appropriate.  See the Exposure Control Plan for more information on needlestick exposures to human blood and other potentially infectious human materials.

3.6.7 Dermal Contact

If a chemical spills on a person, the first goal is to remove the chemical from the person’s skin as soon as possible, without spreading it onto yourself. For chemicals that can cause burns, the stronger the chemical and the longer the contact, the worse the burn. The chemical continues to burn as long as it remains on the skin. For all chemicals except hydrofluoric (HF) acid (see section 5.1.1 First Aid Procedure for Responding to Hydrofluoric Acid Burns), flush the skin under running water or a safety shower for at least 15 minutes. For limited skin exposure on a small area, a drench hose may be adequate for flushing.

Remove contaminated clothing while the person is under the shower stream, taking care not to spread contamination from the clothing onto more of the person’s skin. If the clothing must be pulled over the head or down along the legs to be removed, cut it away with first aid kit scissors instead. Many safety showers are equipped with curtains to give privacy to the victim. Don’t let modesty keep you from removing contaminated clothing that remains against skin.

Do not treat the burn. Do not puncture any blisters that may develop. Allow trained medical personnel to administer treatment after flushing is complete. Your first aid kit will probably contain antibiotic ointment and sterile gauze for burns. These are intended only for minor burns such as those you might encounter in your household, e.g., small burns from cooking at a stove and sunburns.

It is advisable for pregnant women to avoid touching anything in a laboratory space bare-handed. Disposable gloves provide a barrier from low level contamination of common surfaces.

3.6.8 Eye Contact

Should a chemical enter a person’s eye(s), wash the eye(s) with running water for at least 15 minutes, while waiting for medical help to arrive. Keep the affected eye (if only one has been contaminated) lower than the unaffected eye to prevent the spread of contamination.

Be aware that particulates and liquids can become trapped in the conjunctiva where they may continue to cause damage. The entire interior of the eye socket must be flushed as well as the exposed cornea.

A “buddy” in the laboratory space is vital to the injured person to help find the eyewash, call for help, keep the eyes open under the water stream, and prevent the person from rubbing the eye(s) and aggravating the damage.

3.7 Critical Failures

Critical failures in research processes or research equipment require immediate action towards cessation. Examples include:

• Unsafe processes that led to work-acquired injury–permanent eye damage or hospitalization
• Apparently work-acquired infection or possibly work-acquired high contaminant levels found in body fluids, hair, etc.
• Any containers for flammables, reactives, toxics that show evidence of rupture in storage (broken cap, vessel rupture)
• Toxic or highly toxic gas cylinders mounted in use outside of a vented enclosure. In-use cylinders of this content type should be mounted for use in a vented gas cabinet or fume hood.
• For high-pressure flammable gases: no flash arrestor downstream of gas cylinder to usage device
• In-use flammable or toxic gas cylinders with regulators where pressure is greater than the ASME B40.100 (accuracy classes from 0.1 to 5% range) out of spec.
• In-use flammable/toxic gas leakage alarm systems or waste abatement systems without PM/calibration records for last 12 months
• In-use flammable and toxic gas manifolds without an updated process flow diagram
• In-use flammable and toxic gas manifolds missing a check valve preventing accidental back flow conditions. Especially critical for oxy/fuel systems
• In liquid cryogenic flow systems a pipe/tube/vessel area/section that can be valved off without a safety relief valve in place
• Heating devices for flammable or toxic chemistry where the temperature gauge is >5% out of spec
• Inappropriate use of toxic and flammable gas fitting adapters (i.e., wrong CGA type)
• Use of cheater plugs or cheater adaptors to connect devices to a >=110V electrical power source

Laboratory safety and chemical hygiene programs consolidate the compliance programs for the OSHA Hazard Communication Standard, the OSHA Occupational Exposure to Hazardous Chemicals in Laboratories Standard (the “Laboratory Standard”), and other general laboratory safety programs.

4.1 Lumen and the Research Safety Website

PIs use the Research Management Platform Lumen to submit applications and registrations for review. Lumen helps PIs build a lab-specific laboratory-spcific profile and serves as an educational resource for PIs and laboratory members.

The information in Lumen and the Research Safety website is intended to be a central safety resource for the laboratory, shop, and department.

 A PI’s Lumen Profile is the laboratory-specific part of the chemical hygiene plan required by the OSHA Laboratory Standard for research labs, teaching labs, and common facilities (those shared by more than one researcher). In the case of shared facilities, the director, coordinator, or designated facility supervisor is responsible for their Lumen Profile.

If chemical, radioactive or biological agents or processes with lasers, physical or health hazards are used, the PI shall request a Lumen Profile.

PIs are responsible for keeping their Lumen Profile current. At a minimum, a review and update should be conducted annually and when there are changes to personnel, space or required registrations. The  Laboratory Safety Profile shall reflect current job activities which affect occupational exposure.

If a PI opens a new laboratory space or moves to an alternate location, advise Research Safety.

4.2 Laboratory Inspections

The University provides an inspection program for all laboratories. Laboratory inspections are conducted by Research Safety staff.

The inspection consists of an interview with the laboratory representative followed by a visit to the laboratory. Investigators may be asked to update their Lumen Profile and other information. The Research Safety representative may examine general laboratory conditions, engineering controls, work practices, chemical storage, use of personal protective clothing and equipment, signs and postings, and availability of documents such as SDSs. Laboratory members may be interviewed. Inspection findings are detailed in the Lumen Profile. If corrections are needed, PIs are required to respond within two weeks.

Working safely in a laboratory requires having the proper containment equipment and engineering controls, wearing appropriate personal protective equipment, using proper work practices, knowing safety information for the materials and equipment used, and following safety instructions and laboratory protocols.

Because each laboratory situation is different, judgment is required in interpreting general concepts for individual settings. The Lumen Profile provides specific information for individual laboratories.  

5.1 First Aid Kits

Medical care at the University is available through the University Health Service, the occupational medicine providers for each respective campus, and local hospitals. On the campuses, a 911 call summons paramedics within minutes.

PIs are responsible for supplying at least one first aid kit for their lab groups. If the same group occupies spaces that are not in immediate proximity (i.e., labs in different buildings or on different floors), a first aid kit shall be available for each set of labs.

First aid kits and first aid training are also required for research activities away from the campus especially in remote areas where medical care is not readily available.

Factors to consider in selecting a kit include the following:

• The supplies should be consistent with the types of injuries anticipated in this research space (e.g., will there be burns, cuts, fractures, contusions, or allergic reactions).
• Supplies should be provided in single-use or -dose unit-type packs with suitable wrapping to ensure sterility and hygiene.

As a practical model, the American National Standards Institute’s Minimum Requirements for Workplace First Aid Kits (ANSI Z308.1-1998) recommends that basic units should contain:

• 1 absorbent compress (32 sq. in. with no side smaller than 4 in.)
• 16 adhesive bandages (1 x 3 in.)
• Adhesive tape (total of 5 yd.)
• 10 individual-use antiseptic applications (0.5 g each)
• 6 individual-use burn treatment applications (0.5 g each)
• 2 pairs of medical exam gloves
• 4 sterile pads (3 x 3 in.)
• 1 triangular bandage (40 x 40 x 56 in.) and
• 1 scissors

It shall be inspected regularly to ensure that no items are missing and that none of the remedies (e.g., saline solution, ointment) in the kit have expired.

The LCSC and Research Safety encourage CPR and first aid training for at least 2 lab members in each lab group. Such training can be arranged through Research Safety.

If there are lab members who have particular sensitivities or medical problems that could interfere with first aid procedures, consider discussing this issue with the entire staff. Barring any confidentiality concerns, it is wise to prepare colleagues for possible reactions or symptoms should an employee suffer from an illness that demands special care. An employee with a given medical condition (e.g., severe allergies, asthma, heart disease) may require prescription drugs during a respiratory attack or illness episode.

5.1.1 First Aid Procedure for Responding to Hydrofluoric Acid Burns

Hydrofluoric acid (HF) is an extremely hazardous liquid. It can cause severe skin and eye irritation or deep-seated, slow-to-heal burns. In certain cases, exposure can prove fatal. For any major exposure to HF, immediate paramedic assistance is necessary.

HF’s mode of action is to bind calcium whenever contact occurs with skin or other body tissues. Unlike the action of other acids, which are rapidly neutralized, tissue destruction and action of HF may proceed for days. Because calcium is necessary for cell life, its binding can bring about rapid cell death. If the HF exposure is extensive, excessive amounts of calcium may be inactivated and inadequate supplies of calcium may be available for vital bodily functions.

Some fluorinated compounds may generate HF either as a reaction side-product or as a result of decomposition.  Labile fluorine in fluorinated organic or inorganic materials may produce HF, particularly through contact with water.  Fluoride ions also form HF when in equilibrium in aqueous solution.  Researchers should consult the SDS of the compound with which they are working and the scientific literature during their preliminary risk assessment to identify whether HF formation is a possible hazard.

Inform the physician treating the HF injury to the nature of the chemical involved in the exposure and deliver a SDS. Some medical providers may not commonly encounter HF. Offer as much information as possible regarding the chemical and its effects. Encourage the physician to consult an occupational specialist for further information, if needed. See also the CDC’s HF page.

For skin exposure ⁶:

• Immediately start rinsing under safety shower or other water source and flush affected area thoroughly with large amounts of water, removing contaminated clothing while rinsing. Speed and thoroughness in washing off the acid is of primary importance.
• Call for emergency response.
• While wearing neoprene or butyl rubber gloves to avoid a secondary aqueous HF burn, massage 2.5% (w/w) calcium gluconate gel onto the affected area after 5 minutes of flushing with water. If calcium gluconate gel is unavailable, continue flushing the exposed areas with water until medical assistance arrives.
• Send a copy of the SDS with the victim.

For eye exposure:

• Immediately flush the eyes, holding eyelids open, for at least 15 minutes with large amounts of gently flowing water, preferably using an eyewash station.
• Do not apply calcium gluconate gel directly onto the eye.
• Seek medical attention.
• Send a copy of the SDS with the victim.

For inhalation:

• Immediately move to fresh air.
• Call 911.
• Send a copy of the SDS with the victim.

For ingestion:

• Seek immediate medical attention.
• Drink large amounts of water or milk as quickly as possible to dilute the acid.
• Do not induce vomiting. Do not ingest emetics or baking soda. Never give anything by mouth to an unconscious person.
• If medical attention must be delayed and the materials are available, drink several ounces of milk of magnesia or other antacids.
• Send a copy of the SDS with the victim.

PIs should assign and require completion of Research Safety developed training content. Calcium gluconate gel (2.5% w/w) must be readily accessible in work areas where any potential HF exposure exists. Check the expiration date of your supply of commercially obtained calcium gluconate gel and replace as needed to ensure a supply of fresh stock. Research Safety provides calcium gluconate gel for labs working with HF and HF-generating materials.

5.2 Personal Hygiene

Personal hygiene is extremely important in a laboratory. Contamination of food, beverages, or smoking materials is a potential route of exposure to toxic chemicals, radioactive materials, or biological agents through ingestion. Thus, laboratory personnel shall not prepare, store, or consume food or beverages, pipette by mouth, smoke, apply lip balm or cosmetics, or handle contact lenses in the work area. This elementary safety rule shall be followed by everyone working in or visiting a laboratory space.

Hand washing is a primary safeguard against inadvertent exposure to toxic chemicals, radioactive materials or biological agents. Always wash your hands before leaving the laboratory space, even though you use gloves. Wash your hands after removing soiled protective clothing, before leaving the laboratory space, and before eating, drinking, smoking, or using a rest room.

Wash your hands periodically during the day at intervals dictated by the nature of your work. Wash with soap and running water, with hands held downward to flush the contamination off the hands. Turn the tap off with a clean paper towel to prevent recontamination and dry your hands with clean towels.

Confine long hair and loose clothing when in the laboratory or in a shop area to keep them from catching fire, dipping into chemicals, or becoming entangled in moving machinery. Avoid wearing finger rings, fingernail extensions and wrist watches which may become contaminated, react with chemicals, or be caught in the moving parts of equipment.

Remove contaminated laboratory coats and gloves before you leave the laboratory. Keep a clean spare coat to wear outside the laboratory. Do not wear gloves outside the laboratory.  

5.3 Personal Protective Clothing and Equipment

You have a responsibility to dress sensibly for laboratory work. Some protection is afforded by ordinary clothing and eyeglasses.

Personal protective clothing and equipment protects you from injury due to absorbing, inhaling, or coming into physical contact with hazardous materials. You are responsible for using special protective clothing and equipment when they are required for safety. Protective wear may include laboratory coats, wraparound gowns, cloth masks, coveralls, aprons, gloves, shoe covers, and respirators. Select garments and fabric based on the nature of the hazardous agent. Laboratory workers must check their PPE for signs of wear or damage and replace the affected equipment immediately.

Research Safety provides a basic set of PPE – lab coat, gloves and eye protection – to all registered laboratory workers. The standard lab coat fabric is 100% cotton. Flame-resistant (FR) lab coats provide additional protection when working with flammable chemicals or processes. FR-rated clothing has a distinctive label affixed to it.

Research Safety facilitates lab coat laundry service. Simply bring a dirty lab coat to the Evanston Research Safety Office or the Chicago Fisher Stockroom. You will receive a clean one of the same size. For those who wish to have their own personal lab coat returned to them, you will need to have it cleaned through Procurement and Payment Services and your department assumes the cost.

Do not wash lab coats or contaminated clothing with other personal laundry.

5.3.1 Clothing

Cover unprotected skin whenever possible. Suitable clothing shall be worn in the laboratory space; shorts are not appropriate. Clothing may absorb liquid spills that would otherwise come in contact with your skin. Long sleeves protect arms and shall fit snugly, especially when you are working around machinery. Nomex and wool affords more protection from flash burns or corrosive chemicals than cotton or synthetic fabrics. Some synthetic fabrics may increase the severity of injury in case of fire. Cotton is less prone to static electricity buildup than nylon or other synthetics.

Wear substantial closed-toed shoes in the laboratory space to protect against chemical splashes or broken glass. Do not wear sandals, cloth sport shoes, perforated shoes, or open-toed shoes. If you clean up a spill from the floor, you may need the added protection of rubber boots or plastic shoe covers. Steel-toed shoes may be required for handling heavy items, such as gas cylinders or heavy equipment components.

Aprons, laboratory coats, gloves, and other protective clothing, preferably made of chemically inert material, shall be readily available and used. Laboratory coats are essential to protect street clothing from biological agent aerosols or chemical and radioactive material splashes and spills, vapors, or dusts. For work involving carcinogens, disposable coats may be preferred. For work with mineral acids, acid-resistant protective wear is desirable.

When the potential for fire exists, consider wearing a laboratory coat specifically designed to be flame retardant. Several types of flame-resistant clothes are available from safety suppliers. A low-cost option is a disposable cotton coat that has been treated with a flame-resistant material. The treatment slows combustion and provides an additional level of protection from fire and heat. However, repeated washing degrades the chemical treatment and compromises fire protection.

More durable flame-resistant cotton laboratory coats are also available. A fabric known as Nomex provides the best protection against flame hazards. This material has a structure that thickens and carbonizes when exposed to heat. This unique characteristic gives Nomex lab coats excellent thermal protection. Because the characteristics of the material are inherent to the fiber, repeated laundering does not change the thermal protection capabilities.

5.3.2 Eye Protection

Eye protection is mandatory in laboratory spaces because of the obvious hazards of flying objects, splashing chemicals, and corrosive vapors. Eyes are very vascular and can quickly absorb many chemicals. Regulations require protective eye and face equipment where there is a reasonable probability that using them can prevent injury. Eye protection shall be required in all laboratories where chemicals are used or stored. Eye protection is not interchangeable among employees and shall be provided for each individual unless disinfected after use.

Safety glasses with clear side shields are adequate protection for general laboratory use. Goggles shall be worn when there is danger of splashing chemicals or flying particles, such as when chemicals are poured or glassware is used under elevated or reduced pressure. A face shield with goggles offers maximum protection (for example, with vacuum systems that may implode).

Corrective lenses in spectacles do not in themselves provide sufficient protection. Wear goggles over your eyeglasses, or order prescription safety glasses through Eyelation. Online Eyelation access for Northwestern University faculty, staff and students is available through the Research Safety offices.  

TABLE 5.3.1  PROPERTIES OF PROTECTIVE CLOTHING MATERIALS*

* Based on manufacturer’s claims. From Chemical Safety Manual for Small Businesses, American Chemical Society, third edition, 2007.  

5.3.3 Gloves

Gloves are worn to prevent skin contact with toxic, radioactive or biological agents, burns from hot or extremely cold surfaces or corrosives, or cuts from sharp objects. Glove usage and artificial fingernail extensions are not compatible. Many gloves are made for specific uses. For adequate protection, select the correct glove for the hazard in question.

Leather and Kevlar gloves provide good protection for picking up broken glass, handling objects with sharp edges, and inserting glass tubing into stoppers. Cuts from forcing glass tubing into stoppers or plastic tubing are a common laboratory accident and are often serious. However, because they absorb liquid, these gloves do not provide protection from chemicals, nor are they adequate for handling extremely hot or cold surfaces. Gloves designed to insulate against hot surfaces and dry ice are not suitable for handling other chemicals.

Sometimes the ideal glove is actually two gloves worn together. Wearing one pair of gloves (such as reusable nitrile, neoprene, butyl, or Viton) over a flexible laminate combines the advantages of both.

⁷When choosing an appropriate glove, consider the required thickness and length of the gloves as well as the material. Consult the glove manufacturer for chemical-specific glove recommendations and information about degradation and permeation times. Certain disposable gloves should not be reused.

• Butyl is a synthetic rubber with good resistance to weathering and a wide variety of chemicals.
• Natural rubber latex is a highly flexible and conforming material made from a liquid tapped from rubber plants. Use of latex is not recommended as it can cause allergic reactions.
• Neoprene is a synthetic rubber having chemical and wear-resistance properties superior to those of natural rubber.
• Nitrile is a copolymer available in a wide range of acrylonitrile content; chemical resistance and stiffness increase with higher acrylonitrile content.
• Polyethylene is a fairly chemical-resistant material used as a freestanding film or a fabric coating.
• Poly (vinyl alcohol) is a water-soluble polymer that exhibits exceptional resistance to many organic solvents that rapidly permeate most rubbers.
• Poly (vinyl chloride) is a stiff polymer that is made softer and more suitable for protective clothing applications by the addition of plasticizers.
• Polyurethane is an abrasion-resistant rubber that is either coated into fabrics or formed into gloves or boots.
• 4H® or Silvershield® is a registered trademark of North Hand Protection; it is highly chemical-resistant to many different classes of chemicals.
• Viton®, a registered trademark of DuPont, is a highly chemical-resistant but expensive synthetic elastomer.

Chemicals can eventually permeate all glove materials. Select glove materials resistant to the chemical being used, and change gloves periodically to minimize penetration. The chemical resistance of common glove materials varies according to the glove manufacturer, as manufacturers may vary the thicknesses and formulations of materials. Consult Research Safety for concerns regarding glove selection.

General guidelines to the selection and use of protective gloves:

• Do not use a glove beyond its expiration date. Gloves degrade over time, even in an unopened box.
• When not in use, store gloves in the laboratory space but not close to volatile materials. Do not don or doff gloves in offices, in break rooms, lunchrooms or common hallways.
• Inspect gloves for small holes, tears, and signs of degradation before use.
• Replace gloves periodically because they degrade with use, depending on the frequency of use and their permeation and degradation characteristics relative to the substances handled.
• Replace gloves immediately if they become contaminated or torn.
• Decontaminate or wash gloves appropriately before removing them. [Note: Some gloves, e.g., leather and poly (vinyl alcohol), are water permeable. Unless coated with a protective layer, poly (vinyl alcohol) gloves will degrade in the presence of water.]
• Gloves on a glovebox should be inspected with the same care as any other gloves. Disposable gloves appropriate for the materials being handled within the glovebox should be used in addition to the gloves attached to the box. Protect glovebox gloves by removing all jewelry prior to use.

5.3.4 Respirators

When feasible, engineering controls shall be provided to minimize exposure to airborne hazards. If accepted engineering control measures are not available to prevent or protect against harmful levels of airborne contaminants, employers are required to provide respirators at no cost to employees and employees are required to wear them. Respirators are considered a last resort of protection against exposure to inhalation hazards after all practicable engineering options have been exhausted.

Persons desiring to use a respirator shall inform Research Safety and obtain information on the requirements. These requirements are mandated by the OSHA Respiratory Protection Standard and are described in the University’s Respiratory Protection Program.

A hazard evaluation shall be conducted to determine whether the employee or student is required to wear a respirator or whether engineering controls can eliminate the hazard. If the need for a respirator is established, or if a researcher wishes to wear a respirator on a voluntary basis, the wearer must register with Research Safety.  

5.4 General Laboratory Protocol

All laboratory protocols shall include basic safety precautions. These include personal hygiene, work practices, and the appropriate personal protective clothing and equipment needed to protect from exposure to chemicals, radioactive materials or biological agents.

5.4.1 Housekeeping

Wise up, suit up, clean up!

Keeping things clean and organized helps provide a safer laboratory space. Laboratory surface cleanliness is especially important for laboratory workers of reproductive age and pregnant women. Keep drawers and cabinet doors closed and electrical cords off the floor to avoid tripping hazards. Keep aisles clear of obstacles such as boxes, chemical containers, and other storage items that might be put there even temporarily. Avoid slipping hazards by cleaning up spilled liquids promptly and keeping the floor free of stirring rods, glass beads, stoppers, and other such items. Never block or even partially block the path to an exit or to safety equipment, such as a fire extinguisher or safety shower.

Make sure that supplies and equipment on shelves provide sufficient clearance so that fire sprinkler heads operate correctly. There shall not be any storage within 18 inches of a sprinkler head.

Put ordinary wastepaper and wrappings in a labeled trash can. When discarding empty boxes or other containers bearing hazardous materials labels, the labels shall be defaced or removed before disposal. Dispose of broken glass and other sharp items in a rigid, puncture-resistant container to protect persons collecting the waste materials. Needles and syringes must be disposed of in a rigid, puncture-resistant sharps container.

Chemical wastes and unwanted chemicals shall be disposed of promptly and not left to clutter a laboratory space. Follow all procedures of the Hazardous Waste Disposal Guide (Purple Guide). Additional information is available on disposal of human body fluids or other potentially infectious materials.

5.4.2 Cleaning Glassware

When cleaning laboratory glassware, wear appropriate cut-resistant gloves. Avoid accumulating too many articles in the cleanup area around the sink; space is usually limited and piling up glassware leads to breakage.

Many fingers have been badly cut by broken glass from glassware that was intact when put into the sink water. Handle glassware carefully and watch out for broken glass at the bottom of the sink. A rubber or plastic mat in the sink will help minimize breakage.

If you must use hazardous substances such as solvents or acids for cleaning glassware, you must be thoroughly familiar with those materials’ hazards and use appropriate protective equipment.

Avoid using strong cleaning agents such as nitric acid, chromic acid, sulfuric acid, strong oxidizers, or any chemical with “per” in its name (perchloric acid, ammonium persulfate, etc.) unless no alternatives are available.

Flammable solvents such as acetone should be used in minimum quantities for cleaning and with appropriate precautions taken during their use.

Acids and solvents shall not be rinsed down the drain during cleaning but shall be collected for proper treatment and disposal.

5.4.3 Laboratory Animals

Federal regulations require that the Institutional Animal Care and Use Committee (IACUC) review and approve the use of animals in research. The Center for Comparative Medicine (CCM) administers all activities related to the care and use of animals and mandates compliance with standard operating procedures.

Laboratory animals may be potential sources of hazardous chemical exposure from metabolic products, wastes, cage litter, and contaminated cages. The preparation of food and water containing toxic substances under investigation shall be done with all precautions ordinarily taken to protect the health and safety of personnel. The OSHA Laboratory Standard guidelines for animal work with chemicals of high chronic toxicity shall be followed. The guidelines cover administration of the toxic substance, aerosol suppression, personal protection, and waste disposal.

Another possible concern in handling laboratory animals is the potential for exposure to inherent biological hazards. Aside from the biological agents to which the animals are deliberately exposed, lab animals may harbor indigenous pathogens that can be transmitted to humans. This is of particular concern with nonhuman primates. In the case of macaque monkeys, animal handlers may contract Cercopithecine herpesvirus ([CHV-1], commonly referred to as Herpesvirus simiae or “B-virus”) infection that can be deadly. The virus is primarily transmitted through bites, scratches, or other contamination of broken skin; however, a fatality due to a splash of a macaque’s body fluid in the eye has been reported. The high risk of infection places particular importance on the wearing of personal protective equipment to prevent exposure. Animal handlers working with macaques and other nonhuman primates shall follow the standard operating procedures from CCM and the Training and Occupational Health Program required by IACUC. Always don appropriate gloves, surgical masks, splash goggles, and lab coats or other suitable covering that leaves no exposed skin or mucous membranes.

Access to gaseous anesthetics and the operation of anesthesia machines shall be limited to authorized users. Authorized users, in this context, shall have completed safety awareness training.

5.4.4 Relocating or Closing a Laboratory Space

Disposition of all unwanted chemicals is the responsibility of the PI. All chemicals that will not be relocated shall be listed on the Hazardous Waste Pickup Request. The PI remains responsible until all hazardous materials are removed. The department of record is responsible for the safe and lawful cleanup and disposition of all chemical, biological and radioactive materials that are abandoned.

The PI ensures that surfaces and equipment potentially contaminated with hazardous chemicals, radioactive materials or biological agents are decontaminated before the laboratory space is vacated. Accessible surfaces (chemical fume hoods, sinks, bench tops) should be cleaned, when practical, by the PI and staff. If this is not possible, an outside contractor specializing in the testing and cleaning of contaminated laboratory equipment should be contacted. The PI shall provide the contractor with thorough and accurate information pertaining to the past uses of the equipment.

To confirm that a vacated laboratory space is properly emptied of hazardous materials, decontaminated, and ready for new occupants, the PI or laboratory supervisor shall prepare the Laboratory Closeout Checklist. Should the PI fail to complete the items required on the form, the department becomes financially and administratively responsible for the safe disposition of the hazardous materials and the decontamination of work surfaces.

Research Safety offers a laboratory survey to any PI vacating a laboratory space to assist in identifying the tasks that must be finished for clearance of the space.

5.4.5 Transportation and Shipping of Hazardous Materials

The U.S. Department of Transportation (DOT) requires that a licensed hazardous materials transporter be employed if hazardous materials are transported on a public highway, air, or water. DOT also requires that all individuals offering a hazardous material for transport receive appropriate training. Follow the Hazardous Materials Shipping Policy for Laboratories. If in doubt, consult with Research Safety before shipping any hazardous chemicals, radioactive materials, or biological materials. Export control restrictions may apply.

5.4.6 Laboratory Doors

Fire and life safety codes may require that corridor doors be fire rated and equipped with door closers. Doors with door closers are generally kept closed at all times, unless the door release is tied into the building’s fire alarm system. Keeping laboratory doors to corridors closed helps ensure that ventilation systems work properly and maintain contaminant-containing pressure differentials between labs and corridors. This is especially important in newer buildings with sensitive energy conservation systems. Doors in internal laboratory suites may have less stringent door closing requirements.

Viewing windows in corridor halls shall be kept unobstructed unless there is hazardous laser energy that requires curtains or blocking.

5.4.7 Visitors to Laboratory Spaces

Do not allow visitors, including children and pets, in laboratory spaces where hazardous substances are stored or are in use or hazardous activities are in progress. Students from primary and secondary schools occasionally may enter laboratories as part of educational programs under carefully controlled and supervised conditions. Colleagues, prospective students, and others may be invited into laboratory spaces for legitimate academic and research purposes. Each individual working in a laboratory should prudently evaluate the risks to visitors, especially to persons of increased risk such as children and immune-suppressed individuals. Human Resources requires registration of volunteers and interns. Occupational Health requires a signed Volunteers and Visitors Lab Use Agreement.

CCM standard operating procedures require a signed Visitor Hazard and Declaration of Compliance Form.  

5.5 General Laboratory Techniques

5.5.1 Static Electricity

Static electricity may be generated whenever two surfaces are in contact with one another. Examples are processes such as evaporation, agitation, pumping, pouring of liquids, or grinding of solids or powders. Equipment used in these operations shall be bonded and grounded to prevent static charges from accumulating on the containers. Blanketing with inert gas may also prevent sparks in equipment where flammable vapors are present. The buildup of static charge increases at low absolute humidity, as is likely in cold weather. Some common potential sources of electrostatic discharges are ungrounded metal tanks and containers, metal-based clamps, nipples, or wire used with non-conducting hoses, high-pressure gas cylinders upon discharge, and clothing or containers made of plastic or synthetic materials.

5.5.2 Centrifuges

If a tabletop centrifuge is used, make certain that it is securely anchored in a location where its vibration will not cause bottles or equipment to fall. Ensure that the disconnect switch is working properly and shuts off the equipment when the top is opened. Centrifuge rotors shall be balanced each time they are used. Securely anchor and shield each unit against flying rotors. Regularly clean rotors and buckets with non-corrosive cleaning solutions. Always close the centrifuge lid during operation, and do not leave the centrifuge until full operating speed is attained and the machine appears to be running safely without vibration. Stop the centrifuge immediately and check the load balances if vibration occurs. Check swing-out buckets for clearance and support.

5.5.3 Vacuum Work and Apparatus ⁸

Vacuum work can result in an implosion and the possible hazards of flying glass, spattering chemicals, and fire. Set up and operate all vacuum operations with careful consideration of the potential risks. Although a vacuum distillation apparatus may appear to provide some of its own protection in the form of heating mantles and column insulation, this is not sufficient because an implosion could scatter hot flammable liquid. Use an explosion shield and a full-face shield to protect laboratory personnel, and carry the procedure out in a laboratory chemical hood. Glassware under vacuum should be kept behind a shield or hood sash, taped, or resin (plastic) coated.

Equipment at reduced pressure is especially prone to rapid pressure changes, which can create large pressure differences within the apparatus. Such conditions can push liquids into unwanted locations, sometimes with undesirable consequences.

Do not allow water, solvents, and corrosive gases to be drawn into a building vacuum system. When the potential for such a problem exists, use a cold trap. Water aspirators are not recommended.

Precautions to be taken when working with vacuum lines and other glassware used at sub ambient pressure are mainly concerned with the substantial danger of injury in the event of glass breakage. The degree of hazard does not depend significantly on the magnitude of the vacuum because the external pressure leading to implosion is always 1 atmosphere. Thus, evacuated systems using aspirators merit as much respect as high-vacuum systems. Injury due to flying glass is not the only hazard in vacuum work. Additional dangers can result from the possible toxicity of the chemicals contained in the vacuum system, as well as from fire following breakage of a flask (e.g., of a solvent stored over sodium or potassium).

Because vacuum lines typically require cold traps (generally liquid nitrogen) between the pumps and the vacuum line, precautions regarding the use of cryogens should be observed also. Liquid nitrogen–cooled traps open to the atmosphere condense liquid air rapidly. When the coolant is removed, an explosive pressure buildup occurs, usually with enough force to shatter glass equipment if the system has been closed. Hence, only sealed or evacuated equipment should be so cooled. Vacuum traps must not be left under static vacuum; liquid nitrogen in Dewar flasks must be removed from these traps when the vacuum pumps are turned off.

Residues from vacuum distillations have been known to explode when the still was vented suddenly to the air before the residue was cool. To avoid such explosions, vent the still pot with nitrogen, cool it before venting, or restore pressure slowly. Sudden venting may produce a shock wave that explodes sensitive materials.

Vacuum Pumps

Distillation or similar operations requiring a vacuum must use a trapping device to protect the vacuum source, personnel, and the environment. This requirement also applies to oil-free Teflon-lined diaphragm pumps. Normally the vacuum source is a cold trap cooled with dry ice or liquid nitrogen. Even with the use of a trap, the oil in a mechanical vacuum trap can become contaminated and the waste oil must be treated as a hazardous waste.

Vent the output of each vacuum pump to a proper air exhaust system. Vent lines may be Tygon, rubber or copper. If Tygon or rubber lines are used, they should be supported so that they do not sag or cause a trap for condensed liquids. Safe venting is essential when the pump is being used to evacuate a system containing a volatile toxic or corrosive substance. Failure to observe this precaution results in pumping volatile substances into the laboratory atmosphere.

Oil lubricated vacuum pumps should carry tags indicating the date of the most recent oil change. Vacuum pump oil should be changed once a month, or sooner if it is known that the oil has been unintentionally exposed to reactive gases. It may be desirable to maintain a log of pump usage as a guide to length of use and potential contaminants in the pump oil.

Belt-driven mechanical pumps must have protective guards. Such guards are particularly important for pumps installed on portable carts or tops of benches where laboratory personnel might accidentally entangle clothing,hair,or fingers in the moving belt or wheels.

Glass Vessels

Although glass vessels are frequently used in low-vacuum operations, evacuated glass vessels may collapse violently, either spontaneously from strain or from an accidental blow. Therefore, conduct pressure and vacuum operations in glass vessels behind adequate shielding. Check for flaws such as star cracks, scratches, and etching marks each time a vacuum apparatus is used. These flaws can often be noticed if the vessel is help up to a light. Use only round-bottom or thick-walled (e.g., Pyrex) evacuated reaction vessels specifically designed for operations at reduced pressure. Do not use glass vessels with angled or squared edges in vacuum applications unless specifically designed for the purpose (e.g., extra thick glass). Repaired glassware must be properly annealed and inspected with a cross-polarizer before vacuum or thermal stress is applied. Never evacuate thin-walled, Erlenmeyer, or round-bottom flasks larger than 1 liter.

Dewar Flasks

Glass dewar flasks are under high vacuum and can collapse as a result of thermal shock or a very slight mechanical shock. Shield them, either by a layer of fiber-reinforced friction tape or by enclosure in a wooden or metal container, to reduce the risk of flying glass in case of collapse. Use metal jacketed Dewar flasks whenever there is a possibility of breakage.

Styrofoam buckets with lids can be a safer form of short-term storage and conveyance of cryogenic liquids than glass vacuum Dewar flasks. Although they do not insulate as well as Dewar flasks, they eliminate the danger of implosion.

Assembly of Vacuum Apparatus

Assemble vacuum apparatus to avoid strain. Joints must allow various sections of the apparatus to be moved if necessary, without transmitting strain to the necks of the flasks. Support heavy apparatus from below as well as by the neck. Use a bubbler to protect vacuum and Schlenk lines from overpressure. Gas regulators and metal pressure-relief devices must not be relied on to protect vacuum and Schlenk lines from overpressure. If a slight positive pressure of gas on these lines is desired, the recommended pressure range is not in excess of 1 to 2 psi. This pressure range is easily obtained by proper bubbler design (depth of the exit tubing in the bubbler liquid).

Place vacuum apparatus well back onto the bench or into the laboratory chemical hood where it will not be inadvertently hit. If the back of the vacuum setup faces the open laboratory, protect it with panels of suitably heavy transparent plastic to prevent injury to nearby personnel from flying glass in case of implosion.

5.5.4 Drying Ovens and Furnaces

Volatile organics shall not be dried in ovens that vent to the room air. Glassware rinsed with organics should not be oven dried unless it is first re-rinsed with water. Bimetallic strip thermometers rather than mercury thermometers are recommended for measuring oven temperatures. If a mercury thermometer breaks in an oven, the oven shall be turned off and cooled before cleanup is attempted. Wear heat-resistant gloves and appropriate eye protection when working at ovens or furnaces. ANSI-approved eyewear (i.e., heat-absorbing, reflective goggles) offers protection against projectiles and infrared radiation.

5.5.5 Syringes and Scalpel Blades

Syringes used with hazardous agents shall have needle-locking or equivalent tips to assure that the needles cannot separate during use. Do not recap disposable needles after use. Recapping of needles potentially contaminated with human blood, blood products, or other potentially infectious materials is prohibited.

Syringes, needles, or scalpels shall be disposed of immediately after use in sealable, puncture-resistant, disposable containers that are leak-proof on the sides and bottom. The containers shall be appropriately labeled as to the chemical or biological hazard. Sharps containers shall be easily accessible to personnel in the immediate area of use.

5.5.6 Glassware and Plastic Labware

Borosilicate glassware, such as Pyrex 7740, is the type preferred for laboratory experimentation, except in special experiments involving ultraviolet or other light sources or hydrofluoric acid, for which polypropylene containers are most appropriate. Measuring glassware, stirring rods, tubing, and reagent bottles may be ordinary soft glass. Vacuum or suction flasks shall be designed with heavy walls. Dewar flasks and large vacuum vessels shall be taped or otherwise screened or contained in metal to prevent glass from flying if they should implode. An ordinary thin-walled thermos bottle is not an acceptable replacement for a Dewar flask.

Because glassware can be damaged in shipping, handling, or storage, inspect it carefully before using it to be sure it does not have hairline cracks or chips. Even the smallest flaw renders glassware unacceptable and possibly dangerous. Flawed glassware shall be discarded in a rigid, puncture-resistant broken-glass bin. Where the integrity of glassware is especially important, examine for strains using polarized light.

⁹Do not store strong oxidizing agents in plastic labware except that made of Teflon. Prolonged oxidizer exposure causes plastic embrittlement and failure.

5.5.7 Eliminating Mercury Thermometers and Mercury Containing Devices

Metallic mercury is highly toxic by skin absorption, inhalation, and ingestion. Lab members face limited potential exposure whenever they break mercury-filled thermometers. The mercury contamination may infiltrate cracks in benches and the floor or spread beneath equipment and instruments. The contamination is insidious and difficult to remove completely. The difficulty is magnified if the thermometer breaks in a water bath or sink.

One of the best methods for eliminating this hazard and metallic mercury in laboratory spaces is to replace all mercury thermometers with non-mercury instruments. Alternatives to mercury thermometers are spirit-filled or digital units. Research Safety strongly urges you to substitute non-mercury thermometers whenever possible.

Laboratories should pursue alternatives to other mercury-containing laboratory equipment—such as mercury bubblers—whenever feasible.  Replacement of such equipment eliminates mercury-based spill and/or exposure hazards.

Alkyl mercury compounds are extremely toxic and require prior approval from Research Safety before purchase or use.

5.5.8 Ultraviolet, Visible, and Near-Infrared Radiation¹⁰

Ultraviolet, visible, and infrared radiation from lamps and lasers in the laboratory space can produce a number of hazards. Medium-pressure Hanovia 450 Hg lamps are commonly used for ultraviolet irradiation in photochemical experiments. Ultraviolet lights used in biosafety cabinets, as decontamination devices, or in light boxes to visualize DNA can cause serious skin and corneal burns. Powerful arc lamps can cause eye damage and blindness within seconds. Some compounds (e.g., chlorine dioxide) are explosively photosensitive.

When incorrectly used, the light from lasers poses a hazard to the eyes of the operators and other people present in the room and is also a potential fire hazard. See the Laser Safety Handbook for further details about laser registration and hazard control. Glassblowing and the use of laser or ultraviolet light sources require special eye protective glasses or goggles.

5.5.9 Magnetic Fields

See Magnetic Fields on the Research Safety website.

5.5.10 Radio Frequency and Microwave Hazards

Radio frequency (rf) and microwaves occur within the range 10 kHz to 300,000 MHz and are used in rf ovens and furnaces, induction heaters, and microwave ovens. Extreme overexposure to microwaves can result in the development of cataracts or sterility or both. Microwave ovens may be used in laboratory spaces for organic synthesis and digestion of analytical samples. Only microwave ovens designed for laboratory or industrial use should be used in a laboratory. Use of metal in microwave ovens can result in arcing and, if a flammable solvent is present, in fire or explosion. Superheating of liquids can occur. Capping of vials and other containers used in the oven can result in explosion from pressure buildup within the vial. Inappropriately selected plastic containers may melt.¹¹

Microwave heating presents several potential hazards not commonly encountered with other heating methods: extremely rapid temperature and pressure rise, liquid superheating, arcing, and microwave leakage. Microwave ovens designed for the laboratory have built-in safety features and operation procedures to mitigate or eliminate these hazards. Users of such equipment must be thoroughly knowledgeable of operation procedures and safety devices and protocols before beginning experiments, especially when there is a possibility of fire (flammable solvents), over-pressurization, or arcing (Foster and Cournoyer, 2005).

To avoid exposure to microwaves, never operate ovens in disrepair. Do not place wires and other objects between the sealing surface and the door on the oven’s front face. Keep the sealing surfaces absolutely clean. To avoid electrical hazards, the oven must be grounded. If use of an extension cord is necessary, use only a three-wire cord with a rating equal to or greater than that for the oven. To reduce the risk of fire in the oven, do not overheat samples. The oven must be closely watched when combustible materials are in it. Do not use metal containers or metal-containing objects (e.g., stir bars) in the microwave, because they can cause arcing.

In general, do not use heat sealed containers in a microwave oven, because of the danger of explosion. If sealed containers must be used, select their materials carefully and the containers properly designed. Commercially available microwave acid digestion bombs, for example, incorporate a Teflon sample cup, a self-sealing Teflon O-ring, and a compressible pressure-relief valve. Do not exceed the manufacturer’s loading limits. For such applications, properly vent the microwave oven using an exhaust system. Placing a large item, such as a laboratory microwave or an oven, inside a chemical fume hood is not recommended.

Heating a container with a loosened cap or lid poses a significant risk. Microwave ovens can heat material (e.g., solidified agar) so quickly that, even though the container lid is loosened to accommodate expansion, the lid can seat upward against the threads and the container can explode. Screw caps must be removed from containers being microwaved. If the sterility of the contents must be preserved, screw caps may be replaced with cotton or foam plugs.

Although industrial ovens may reduce the risk of such hazards, significant caution is required in their use. In general, the use of closed vessels should be avoided. Any reactions conducted in a microwave oven should be regarded with the same caution as those conducted with highly reactive and explosive chemicals. Reactions should use the smallest scale possible to determine the potential for explosions and fires. Precautions should be taken for proper ventilation and potential explosion.¹²

5.5.11 Extreme Noise

Any laboratory operation that exposes trained laboratory personnel to a significant noise source of 85 decibels(A) or greater for an 8-hour average duration should have a hearing conservation program to protect from excessive exposure. Consult Research Safety to determine the need for such a program and to aid in developing one.

Ultra-sonicators may expose lab members to inaudible mechanical frequencies between 16 and 100 kHz.  Resulting subharmonic frequencies may be audible.  Airborne conduction, direct contact through a liquid-coupling medium, and direct contact with a vibrating solid are routes of exposure.  Avoid direct body contact with liquids or solids subjected to a high-intensity ultrasonic source.    Low intensity ultrasound is safely used for imaging of the human body.  

5.6 Facility Cleaning and Maintenance

A custodial service is contracted to wet-mop floors (including laboratory space) regularly. However, building services and custodial staff are prohibited from cleaning up chemical and biological materials (including spills), and custodians shall not be expected to mop any floors that have not been properly decontaminated after a spill.

In preparation for the cleaning service, the laboratory staff shall remove hazards that the custodians might encounter during their activities. Laboratory occupants shall move chemical and biohazardous waste containers off the floor to a safe and secure location before custodians perform floor cleaning. In the event that a laboratory supervisor does not wish a particular laboratory space to be disturbed, custodial floor cleaning can be suspended. To have the floor cleaning discontinued, post a sign on the lab door. Signs are available from the Research Safety office.

Likewise, if maintenance is required on any component of the laboratory, such as a sink or piece of equipment, the same principles of preparation apply. The supervisor shall ensure that the immediate area is decontaminated and any infectious agents or chemicals are removed to another secure area prior to initiation of work. The laboratory supervisor shall inform maintenance personnel of the presence of any hazardous materials to which they might become exposed. Facility maintenance and custodial staff shall not handle or remove hazardous waste bags or other containers.

Cleaning duties that are the specific responsibility of laboratory personnel shall be conducted on a regular basis to prevent accidental contact with hazards and to reduce clutter in the laboratory space. Laboratory equipment, including refrigerators, freezers, and work surfaces, shall be cleaned by laboratory staff. In laboratories using large amounts of powdered carcinogens, reproductive toxins, or acutely toxic materials, lab members should avoid dry mopping or sweeping with a broom if this could cause the materials to become airborne. Pregnant women shall not be assigned to clean hazardous materials spills.

Facility maintenance and custodial staff shall not handle or remove hazardous waste bags or other containers.  

5.7 Signs and Labels for Laboratories

An “Emergency Information” sign shall be posted outside all laboratories, either on the outside of the door or on the wall beside the door. This sign shall provide information on special precautions for entry, and telephone numbers of responsible faculty and staff.  

5.8 Laboratory Safety and Chemical Hygiene Training

Laboratory member safety training is required under the OSHA Laboratory Standard and additional general industry standards (e.g., the OSHA Personal Protective Equipment Standards, Respiratory Protection Standard, etc.). University policy prohibits persons without appropriate training from being assigned to work independently in laboratory spaces and other areas where hazardous chemicals are used.

Research Safety provides general, regulatory-required laboratory safety training to laboratory members in order to begin their training process. PIs shall provide personalized, hands-on training that ensures lab members are familiar with safe work practices, engineering controls, and personal protective equipment required to safely conduct the hazardous processes, operate equipment or machinery, and handle chemicals specific to their laboratory.

PIs can manage training requirements for Research Safety-provided training inside the Training Module of Lumen. Lab members can use the Training Module to view their training status and enroll in safety training courses.

Research Safety is available to assist with evaluation of training requirements and can provide general safety seminars for laboratory or department groups.

7.1 Corrosives: Acids and Bases

Under hazardous waste regulation a pH <2 or >12.5 indicates corrosive characteristics. Corrosive acids and bases attack the skin and can cause permanent damage to the eyes. Therefore, exercise great care in attempting neutralization.

All the hydrogen halide acids are serious respiratory irritants. Hydrofluoric (HF) acid poses a special danger; both its gas and solutions are toxic, and it is rapidly absorbed through the skin, penetrating deeply into the body tissues. Contact with dilute solutions of hydrofluoric acid may cause no pain for several hours but result in serious burns. In all cases, immediate and thorough flushing with water for 5 minutes, followed by calcium gluconate antidote gel application and prompt attention by a physician are necessary.

Oxyacids such as sulfuric and nitric acid have widely differing properties. Sulfuric acid is a very strong dehydrating agent. When preparing solutions, always add the acid to water and remember that the heat of solution may produce a large increase in temperature. Nitric acid is a strong oxidizing agent that acts rapidly and turns exposed skin yellow to brown as a denaturing reaction occurs. Paper that has been used to wipe up nitric acid spills can ignite spontaneously when dry and should not be thrown into a wastebasket until first rinsed with water and neutralized.

Chromic acid is generally prepared as a cleaning solution; Research Safety recommends the use of replacement cleaners without chromium, which is carcinogenic. All chromic acid waste shall be collected and disposed of through Research Safety. For information regarding chromic acid substitutes, contact Research Safety.

Perchloric acid is a powerful oxidizing agent that may react explosively with organic compounds and other reducing agents. Small quantities of perchloric acid <72% at room temp or below can be used in a regular chemical hood. Any work with perchloric acid heated above ambient temperature requires Research Safety approval. If heated, it shall be used only in a perchloric-acid hood of noncombustible construction. Special hood wash-down features may be required. Perchloric acid should be handled with extreme care and kept from organic matter to prevent a serious explosion. Beakers of fuming perchloric acid >86% shall be handled with tongs rather than rubber gloves. Perchloric acid hoods shall be washed down after every perchloric acid digestion.

Perchloric acid containers shall be stored in glass outer containers and shall not be stored on wood shelving, as drips or leaks may render the wood shock-sensitive. Keep perchloric acid bottles on glass or ceramic trays that are large enough to hold all the acid if the bottle breaks. Storage of perchloric acid containers should not exceed one year. Digest organic matter with nitric acid before addition of perchloric acid. Never heat perchloric acid with sulfuric acid because dehydration may produce anhydrous perchloric acid, which is explosive.

Perchlorate esters have the same shattering effect as nitroglycerine. Transition metal perchlorates are capable of exploding. Perchlorates shall not be used without prior consultation with Research Safety.

Concentrated Bases

The most common bases found in laboratory spaces include the alkali metal hydroxides and aqueous solutions of ammonia. Sodium and potassium hydroxides are extremely destructive to both skin and eye tissues. When concentrated solutions are prepared, the heat of solution can raise the temperature to dangerous levels. Because ammonia solution vapors are such strong irritants, they should be used only in a chemical fume hood.

Table 7.1

Procedure for Inorganic Acid Neutralization (Does not apply to chromic acid)

7.2 Flammable and Combustible Liquids

Definitions

According to most fire codes and regulations, including those for laboratory spaces, a flammable liquid is a liquid with a flash point below 100°F and a vapor pressure not exceeding 40 psi (absolute) at 100°F; it is called a Class I liquid. A liquid with a flash point at or above 100°F is classified as a combustible liquid and may be referred to as a Class II or Class III liquid. See also OSHA Flammable and Combustible Liquids.

The U.S. Department of Transportation (DOT) and the U.S. Environmental Protection Agency (EPA) use a different definition. These agencies define flammable liquids as those with a flash point of 140°F or lower and combustible liquids as those with a flash point greater than 140°F but less than 200°F. DOT and EPA definitions apply primarily to chemicals in transit and hazardous waste.

Flash point is the minimum temperature at which the liquid gives off vapors in sufficient concentration to form an ignitable mixture with air. The classes of liquids are further divided into subclasses, depending on the flash points and boiling points of the liquids (Table 7.2A). The classifications are important because regulations governing storage and use of a liquid are largely based on the liquid’s flash point.

Flammable liquids shall be handled only in areas with no ignition sources and shall not be heated with open flames. If flammable liquids in metal containers or equipment are transferred, the equipment and containers shall be bonded to avoid static-generated sparks.

A more thorough hazard review should be done when flammable reagents are used where the flash point is <10°C, the lower flammable limit is <10%, the auto ignition temperature is <200°C, or the minimum ignition energy is <0.5mJ.³³

Storage

Flammable liquids shall not be stored in ordinary refrigerators or cold rooms. If it is necessary to refrigerate flammable materials, “explosion-proof,” “explosion-safe” or flammablestorage refrigerators shall be used. Combustible liquids are less of a fire hazard, although a rise in temperature increases their evaporation rate and the potential for ignition. If the quantity of flammable liquids in storage exceeds 40 liters (including liquid waste), flammable-liquid storage cabinets shall be used.

Allowable Quantities

The maximum allowable size of containers and portable tanks for flammable and combustible liquids is shown in Table 7.2B. Although the table indicates that the maximum allowable size of glass containers for Class IA and Class IB are 500 ml and one liter respectively, the liquids may be stored in glass containers of not more than 4 liter capacity if the required liquid purity (such as ACS analytical reagent grade or higher) would be affected by storage in metal containers or if the liquid would cause excessive corrosion of the metal container.

Bonding and Grounding

When a flammable liquid is poured into or withdrawn from a metal drum, the drum and the secondary container shall be electrically bonded to each other and to the ground to avoid the possible buildup of a static charge. Quantities no larger than 4 liters³⁴ can be transferred to a glass container. If the liquid is transferred from a metal container to glass, the metal container should be grounded. Greater than 20 liter drums of flammable liquids are not permitted in laboratory spaces unless the quantity is necessary for daily use and is approved by Research Safety. In Evanston, transfer of a flammable liquid by gravity from a drum or carboy is permitted only through a self-closing valve or faucet. Chicago Fire Code for Flammable Liquids prohibits gravity transfer and requires that the liquid be transferred by pumping from an opening in the top of the container.

TABLE 7.2 A – Flammable Liquid Classification

TABLE 7.2 B – Maximum Allowable Size of Flammable and Combustible Liquid Containers in Laboratory Spaces

Reference: NFPA 45, Fire Protection for Laboratories Using Chemicals, National Fire Protection Association, 1996

7.3 Highly Reactive Chemicals

Highly reactive and explosive materials used in the laboratory require appropriate procedures.³⁵

 

7.3.1 Organic Peroxides³⁶

Organic peroxides are among the most hazardous chemicals normally handled in laboratory spaces. In addition to reading the SDS, consult the Bretherick’s Handbook of Reactive Chemical Hazards for more in depth information on reactive hazards and associated incidents. As a group, organic peroxides are flammable, low-power explosives and powerful oxidizers that are sensitive to shock, heat, sparks, friction, impact, and light. Many of them are much more shock-sensitive than typical explosives such as TNT.

Purchase and use of peroxides shall be kept to a minimum. Unused peroxides shall not be returned to the container. Glass containers with screw caps or glass stoppers shall not be used. Polyethylene bottles with screw caps are acceptable. Store liquid organic peroxides at the lowest possible temperature consistent with the solubility or freezing point. Liquid peroxides are particularly sensitive during phase changes. Follow the manufacturer’s guidelines.

Reduce the sensitivity of most peroxides to shock and heat by dilution with inert solvents, such as aliphatic hydrocarbons. However, do not use aromatics (such as toluene), which are known to induce the decomposition of diacyl peroxides.

Do not use solutions of peroxides in volatile solvents under conditions in which the solvent might vaporize because this will increase the peroxide concentration in the solution. See also Section 6.9.4 Distillations.

Do not use metal spatulas to handle peroxides because contamination by metals can lead to explosive decomposition. Magnetic stirring bars can unintentionally introduce iron, which can initiate an explosive reaction of peroxides. Ceramic, Teflon, or wooden spatulas and stirring blades may be used if it is known that the material is not shock sensitive.

7.3.2 Peroxide-Forming Chemicals³⁷

Certain common laboratory chemicals form peroxides on exposure to oxygen in air. Essentially all compounds containing C—H bonds pose the risk of peroxide formation if contaminated with various radical initiators, photosensitizers, or catalysts. Over time, some chemicals continue to build peroxides to potentially dangerous levels, whereas others accumulate a relatively low equilibrium concentration of peroxide, which becomes dangerous only after being concentrated by evaporation or distillation. The peroxide becomes concentrated because it is less volatile than the parent chemical.

A related class of compounds includes inhibitor-free monomers prone to free radical polymerization that on exposure to air can form peroxides or other free radical sources capable of initiating violent polymerization. Note that care must be taken when storing and using these monomers—most of the inhibitors used to stabilize these compounds require the presence of oxygen to function properly, as described below. Always refer to the SDS and supplier instructions for proper use and storage of polymerizable monomers.

Excluding oxygen by storing potential peroxide formers under an inert atmosphere (N2 or argon) greatly increases the safe storage lifetime. Purchasing the chemical stored under nitrogen in septum capped bottles is also possible. In some cases, stabilizers or inhibitors (free-radical scavengers that terminate the chain reaction) are added to the liquid to extend its storage lifetime. Because distillation of the stabilized liquid removes the stabilizer, the distillate must be stored with care and monitored for peroxide formation. Furthermore, high-performance liquid chromatography–grade solvents generally contain no stabilizer, and the same considerations apply to their handling.

Types of Compounds Known to Autoxidize to Form Peroxides

• Ethers containing primary and secondary alkyl groups (never distill an ether before it has been shown to be free of peroxide)
• Compounds containing benzylic hydrogens
• Compounds containing allylic hydrogens (C=C—CH)
• Compounds containing a tertiary C—H group (e.g., decalin and 2,5-dimethylhexane
• Compounds containing conjugated, polyunsaturated alkenes and alkynes (e.g., 1,3- butadiene, vinyl acetylene)
• Compounds containing secondary or tertiary C—H groups adjacent to an amide (e.g., 1- methyl-2-pyrrolidinone)

Procedures for Peroxide Testing

1.   Identify and label all peroxide forming chemicals. Peroxide testing labels are available from Research Safety.
2. Date when (1) received and (2) when opened.
3. Visually inspect each container. If there is crystallization or discoloration, treat the bottle as if it contains a dangerous level of peroxides. Notify Research Safety IMMEDIATELY.
4. Dispose of all peroxide formers by the expiration date on the bottle. If the expiration date is not printed, use the following rules: i. Group I- 3 months from manufactured date ii. Group II & III- 12 months from manufacture date (if inhibited); 3 months if uninhibited.
   1. Group I-3 months from manufacture date
   2. Group II & III-12 months from manfucature date (if inhibited); 3 months if uninhibited
5. Test each peroxide former monthly. Record the (1) date, (2) your initials, and (3) the peroxide concentration (if any) on the peroxide testing label. If the concentration of peroxides is above 10 ppm, contact Research Safety for neutralization and disposal.
6. Store peroxide formers in sealed, dark containers with a tight-fitting cap. Avoid heat and light.

Peroxide test strips are available without charge from Research Safety. Use the key below to determine the concentration of peroxides (if any):

Peroxide Table

7.3.3 Peracids and Peroxy Compounds³⁸

Reactions and subsequent operations involving peracids and peroxy compounds should be run behind a safety shield. For relatively fast reactions, the rate of addition of the peroxy compound should be slow enough so that it reacts rapidly and no significant unreacted excess is allowed to build up. The reaction mixture should be stirred efficiently while the peroxy compound is being added, and cooling should generally be provided since many reactions of peroxy compounds are exothermic. New or unfamiliar reactions, particularly those run at elevated temperatures, should be run first on a small scale. Reaction products should never be recovered from the final reaction mixture by distillation until all residual active oxygen compounds (including unreacted peroxy compounds) have been destroyed. Decomposition of active oxygen compounds may be accomplished by the procedure described in Korach, M.; Nielsen, D. R.; Rideout, W. H. Org. Synth. 1962, 42, 50 (Org. Synth. 1973, Coll. Vol. 5, 414).

7.3.4 Polynitro Compounds

Many polynitroaromatic compounds are shock-sensitive, as are some aliphatic compounds containing more than one nitro group. Many of these compounds are sold and stored with 10 to 20 percent water, which desensitizes their reaction to shock, although they are still flammable solids. In addition to reading the SDS consult the Bretherick’s Handbook of Reactive Chemical Hazards for more in depth information on reactive hazards and associated incidents.

Storage

Polynitro compounds shall be stored separately from most chemicals and labeled so they will be easily identified as reactive. They shall not be placed in long-term storage without special posting indicating their presence and removal date. Long-term storage without checking for proper water content may allow the compounds to dehydrate sufficiently to make them highly reactive.

Surplus and waste polynitro compounds shall be given to Research Safety promptly for proper disposal or recycling and not left on a shelf to be forgotten.

If old containers of polynitro compounds are found, including picric acid or dinitrophenyl hydrazine, do not move them without consulting Research Safety. If they are moved, handle them only by the bottom of the container and never by the cap or lid, as friction may cause a violent explosion.

Picric Acid

Dry picric acid is highly explosive and should be brought into a laboratory space only when specifically required. Users should have a thorough understanding of its hazards. Although not explosive when wetted, picric acid solutions may evaporate to leave the hazardous solid. Picric acid should be stored away from combustible materials and should not be kept for extended periods. Old containers of picric acid shall be handled only by Research Safety.

Methyl nitronitrosoguanidine

Methyl nitronitrosoguanidine is a carcinogenic agent that is also shock-sensitive. It shall be stored in a separate area, preferably locked. Waste paper, plastic, and glass contaminated with this material shall be given to Research Safety for proper disposal.

7.3.5 Catalysts

Catalysts such as raney nickel or palladium on carbon shall be filtered from catalytic hydrogenation reaction mixtures with care. The catalyst has usually become saturated with hydrogen and will produce flames spontaneously on exposure to air. The filter cake should not be allowed to become dry. The funnel containing the still-moist catalyst filter cake should be put into a water bath immediately after completion of the filtration. Use a purge gas (nitrogen or argon) for hydrogenation procedures so that the catalyst can be filtered and handled under an inert atmosphere.

7.3.6 Sodium Azide

Sodium azide is a toxic, highly reactive, heat-sensitive, and potentially shock-sensitive material. Because it reacts with metals, Teflon or other nonmetal spatulas shall be used. It shall be stored in a locked cabinet and used with appropriate personal protective gear.

Sodium azide should only be purchased in small quantities, ideally the minimum amount needed in the laboratory space. Consult Research Safety for a list of vendors who supply 10-gram containers of sodium azide. Storage of solid sodium azide is strongly discouraged.

Solid sodium azide, in quantities above 25 g, shall be dissolved when it arrives in the laboratory space. Solutions of sodium azide do not pose the danger of shock-sensitivity associated with the solid form; however, the hydrazoic acid generated when the azide is dissolved is extremely toxic. Therefore, the solution shall always be prepared inside a chemical fume hood.

Consult with Research Safety if planning for a reaction with greater than 5 grams of sodium azide.

7.3.7 Organometallics

Organometallics are organic compounds comprised of a metal or nonmetal attached directly to carbon (RM). Examples are Grignard compounds and metallic alkyls such as alkyl lithiums, triethylaluminum, and trimethylindium. Many organometallics are highly toxic or flammable. Many are also waterreactive and spontaneously combustible in air. Trialkyltins are the most toxic as a group. Most are highly reactive chemically. Special firefighting equipment (e.g., dry chemical powder fire extinguisher) may be needed where organometallics are handled.

7.3.8 Hydrides

Hydrides are inorganic compounds composed of hydrogen and another element, often a metal. Examples include arsine (AsH3), phosphine (PH3), diborane (B2H6), germane (GeH4), stibine (SbH3), and silane (SiH4). The listed hydrides are highly toxic and flammable. They react violently with water and oxidizing agents and pose a dangerous fire risk. Phosphine, diborane, and silane are spontaneously flammable (pyrophiric³⁹) in air.

Certain hydride gases, notably arsine and phosphine, are commonly used as dopants in semiconductor research applications. Arsine is one of the most toxic gases known. It is a potent hemolytic agent (symptoms: red discoloration of the urine and sclera). Phosphine is extremely toxic to organs of high oxygen flow and demand. Thorough emergency planning for accidental releases shall be in place when such gases are to be used in the laboratory space. Provision of air-supply respiratory protection may be called for as well as continuous system monitoring for releases.

When waste gas streams of hydride gases are concentrated they shall be treated (e.g., scrubbing or thermal decomposition) before release into an exhaust duct. Inform Research Safety of the treatment procedures to be applied.

7.3.9 Piranha Solution, Aqua Regia and Related Etches

The preparation of these solutions requires the development of standard operating procedures. Disposal issues are addressed in the Hazardous Waste Disposal Guide.

7.4 Select Agents

Select agents/toxins are agents that the Department of Health and Human Service (HHS) considers to have the potential to pose a severe threat to human health. A list of these agents is found in the select agent regulation (42 CFR 73). A few of the Select Agents are highly toxic chemicals.

High Consequence Livestock Pathogens and Toxins are agents that the Department of Agriculture (USDA) considers to have the potential to pose a severe threat to animal or plant health, or to animal or plant products.

The plant pathogens listed by USDA have been deemed a threat to plant health or products. Agents that post a severe threat to animal health, animal products and also public health are referred to as “Overlap Agents.” These agents appear on both the HHS and USDA list of agents and toxins.

All regulatory and safety issues related to the use of select agents at NU are governed by the Institutional Biosafety Committee.

7.5 Safety Guidelines for Research with Engineered Nanomaterials

7.5.1 Definitions

Engineered nanoparticle⁴⁰  means intentionally created (in contrast with natural or incidentally formed) particle with one or more dimensions greater than 1 nanomater and less than 100 nanometers. The following types of nanoparticles are beyond the scope of this definition:

• Biomolecules (proteins, nucleic acids, and carbohydrates)
• Materials for which an occupational exposure limit (OEL) or national consensus or regulatory standards exists for the nanoscale particles
• Unbound engineered nanoparticles incapable of becoming airborne or not expected to be generated or released
• Nanoscale forms of radiological materials
• Nanoparticles incidentally produced by human activities or natural processes, such as diesel engines and forest fires

Unbound engineered nanoparticle (UNP)⁴¹ means those engineered nanoparticles that, under reasonably foreseeable conditions encountered in the work, are not contained within a matrix that would be expected to prevent the nanoparticles from being separately mobile and a potential source of exposure. An engineered nanoparticle dispersed and fixed within a polymer matrix, incapable, as a practical matter, of becoming airborne, would be “bound,” while such a particle suspended as an aerosol or in a liquid would be “unbound.”

Universal Precautions⁴² is an approach to infection control that assumes human biological materials are potentially infectious. Under this approach, Personal Protective clothing and Equipment (PPE), work practices, and engineering controls are always used.

7.5.2 Health and Safety

Engineered very small particles exhibit properties different from larger particles of the same chemical composition, making them of interest to researchers and of potential benefit to society. Only limited information is currently available on the toxicity of engineered nanomaterials such as carbon or metal nanotubes, nanowires and sheets, fullerenes, quantum dots, carbon and metalorganic frameworks, metal or silica nanoparticles and other compounds. It is believed that exposure to some unbound engineered nanomaterials may result in health effects. Solid or liquid materials that are comprised (in part) of engineered nanomaterials may be sources of airborne nanoparticles, for example, as a result of abrasion or cutting of solid materials, drying, or agitation of liquid suspensions.

Laboratory research commonly involves handling nanomaterials in liquid suspensions or other forms that do not become easily airborne, and even UNP tend to agglomerate to a larger size. When research involves work with engineered nanoparticles for which toxicity is not yet known, it is prudent to assume the engineered nanoparticles may be toxic, and to handle the engineered nanoparticles using exposure controls that limit inhalation, skin absorption, ingestion and injection.

7.5.3 Standing Operating Procedures

See also the NIOSH Poster “Controlling Health Hazards when Working with Nanomaterials: Questions to Ask Before you Start“.

Hazard Communication

Principal Investigators purchasing, growing, or otherwise generating engineered nanomaterials in their laboratory spaces should include these materials on their chemical inventories, note their presence in the Lumen Profile and communicate required precautions and exposure controls to their laboratory members and others potentially exposed.

Engineering Controls

• Exhausted enclosures are required for handling and weighing of UNP.
• Furnaces used for engineered nanomaterials must be connected to dedicated exhaust ventilation.
• Where gram quantities of UNP are utilized in an exhausted enclosure, HEPA filtration of the exhaust air may be necessary.

Work Practices

​The practices for safely working with engineered nanomaterials are essentially the same as one would use when working with any research chemical of unknown toxicity. Consideration should be taken to:

• Wet wipe work surfaces, such as benchtops where engineered nanomaterials, fibers, or solutions have been handled at the end of each day. Surface contamination with engineered nanomaterials may not be visible.
• Use gloves for handling dry or liquid materials. When nanomaterials are present in a solvent carrier, glove selection should be based on the suitability of the glove for protection against the particular solvent.
• Use universal precautions when liquid phase engineered nanomaterials are used in biological research.
• Utilize NIOSH-approved respirator filters that are rated as N-, R- or P-100 (HEPA) for respiratory protection where airborne exposure to engineered nanomaterials is expected (e.g. cleanout of systems used for growth of carbon nanotubes.).
• Dispose of engineered nanomaterials through Research Safety.
• Label engineered nanomaterials waste containers with the full chemical name or name of mixture and “engineered nanomaterials”.
• Decontaminate equipment contaminated with engineered nanomaterials before decommissioning.

Additional Sources

NIOSH – Approaches to Safe Nanotechnology: Managing the Health and Safety Concerns Associated with Engineered Nanomaterials

National Nanotechnology Initiative

US Environmental Protection Agency (EPA)

Hazards can result from improper handling of gas cylinders and high-pressure equipment. A leaking cylinder can produce an atmosphere that is toxic, anesthetic, asphyxiating, or explosive; and in the event of a rapid escape, a cylinder can become a randomly directed missile. The main purpose of properly handling compressed gases is, therefore, to prevent uncontrolled escape of the gas.

A non-flammable inert compressed gas is defined by the Department of Transportation (DOT) as "any material or mixture which exerts in the packaging an absolute pressure of 280 kPa (40.6 psia) or greater at 20C (68F)".

At Northwestern University most laboratory gases are ordered through Procurement.

8.1 General Precautions

• Never drop cylinders or permit them to strike each other violently.
• Do not expose cylinders to temperatures higher than 122F (50C). Some rupture disks on cylinders release at about 149F (65C).
• Never tamper with pressure relief devices in valves or cylinders.
• Before using cylinders, need all label warnings and Safety Data Sheet warnings associated with the gas being used.
• If a gas cylinder or dewar is in disrepair, affix a repair label and notify Procurement. Repair labels are available in the Research Safety offices.

8.1.1 Types of Compressed Gas Cylinders

There are three major groups of compressed gases stored in cylinders.

• Liquefied gases are partially liquid at normal temperature and charge pressure. Examples: chlorine, propane, nitrous oxide.
• Non-liquefied gases are entirely gaseous at normal temperatures regardless of charge pressure. Examples: argon, oxygen, nitrogen, hydrogen. The standard 5 foot gas cylinders supplied by gas vendors at a pressure of 2,200-2,400 psi contain an average of 250 cubic feet of gas at normal temperature.
• Dissolved gases are dissolved in a liquid phase solvent. Dissolved gas cylinders are packed with an inert, porous filter saturated with the solvent which stabilizes the volatile gas. Acetylene is the only common dissolved gas.

Some gases, such as carbon dioxide, are commonly used in both a liquid and gas form. Cylinders designed for liquid phase dispensing have a siphon, or "dip", tube.

8.1.2 Securing Cylinders

Secure the cylinder above its center of gravity (~2/3 up the cylinder). If the chain or belt is too low or too high, it will not hold the cylinder securely. Keep the cylinder valve-protection cap on when not in use. Secure cylinders by metal channels, nylon bench straps, or chains.

8.1.3 Lecture Bottles

In addition to standard precautions, the following special rules apply to work with lecture bottles in the laboratory:

• Lecture bottles do not have pressure-relief devices to prevent rupturing or a transport cap.
• Unlike larger cylinders, lecture bottles all have identical valve threads, irrespective of the gas contained within.
• If labels and valve tags do not agree, or if there is any question as to the contents of a lecture bottle, return the unused bottle to the supplier or contact Research Safety. Whenever possible, purchase lecture bottles from suppliers who will accept the return of empty or partially empty bottles.
• When transporting lecture bottles, use a cart and block the bottles to prevent rolling and falling.

8.1.4 Storage

Maximum allowable storage quantities vary depending on campus, building, floor, control area, fire rated design and type of gas. Only cylinders that are in use shall be kept in the laboratory. When the cylinder is not in use, close the main cylinder valve tightly and add the protective valve-protection cap.

Promptly remove the regulator from an empty cylinder, replace the valve-protective cap, and label the cylinder by using an “empty” tag or writing on the side of the cylinder with chalk. Never bleed cylinders completely empty; leave a slight pressure to keep contaminants out. Empty cylinders shall be promptly removed.

8.1.5 Return and Transport

Transport using a wheeled cylinder cart with the capped cylinder strapped to the cart. Do not move a gas cylinder that may have been exposed to fire or excessive heat. Notify Research Safety or Procurement.

8.1.6 Fittings and Connections

Threads on cylinder-valve outlet connections have been standardized by the Compressed Gas Association for specific gas types.

This prevents accidental mixing of incompatible gases from an interchange of connections.

Left hand fittings for fuel gases have a cut mark through the nut. Do not use cheaters or adapters that circumvent the CGA fittings.

Compression fittings require no pipe sealants. Follow the Pipe Sealants Guide.

Never lubricate, modify, force, or tamper with cylinder valves. Especially do not put oil or grease on the high-pressure side of a cylinder containing oxygen, chlorine, fluorine or another oxidizing agent. An auto ignition or explosion could result. Unlike larger cylinders, lecture bottles all have identical valve threads, irrespective of the gas contained within.

8.2 Regulators

Table 8.2.1 Common Laboratory Gases and CGA Regulator Fittings

Regulators and fittings are gas-type specific which limits interchange and adds safety. Special installation processes, not mentioned here, are used for toxic or high purity gases. Always make sure that the regulator and valve fittings are compatible.

To select the appropriate regulator:

1. Determine the gas pressure needed.
2. Determine the maximum pressure the system may require
3. Select a delivery pressure range so the required pressures are in the 25%-90% range of the regulator delivery pressure.
4. Check with the gas supplier about compatible connections and regulators.

Check cylinder outlet and regulator inlet connections for debris or contamination before connecting. Some gases, such as carbon dioxide, require a gasket/washer. Ensure that a required gasket is in place before assembling the regulator onto the cylinder.

1. Tighten the connection nut with a smooth jaw wrench.
2. Back out the pressure adjusting knob or key on the regulator.
3. Open the cylinder valve just enough to indicate pressure on the regulator gauge (no more than one full turn).
4. Check connections with a soap solution for leaks. Never use oil or grease on the regulator of a cylinder valve.

All compressed gas regulators should, at a minimum, be checked for external leakage and internal leakage (creep or crawl) regularly. Regulators should be removed from service at least every five years (more frequent in some cases) and returned to the manufacturer, or a competent agent to be inspected and/or refurbished as necessary. Regulators should also be tagged or labeled to identify the last date of inspection. Users should consult the manufacturer for specific procedures on how to check for external and internal leakage as well as the recommended frequency of the tests. Regulators are continuously exposed to high stresses due to cylinder pressures. In addition to that, the materials of construction are attacked internally by both mildly and severely corrosive gases. External corrosive environments can cause gauges and springs to corrode. Argon, helium and nitrogen regulators (CGA 580) will, under a given set of conditions, have a longer service life than regulators used for hydrogen chloride and hydrogen sulfide (CGA 330) simply because the gas service is more severe (corrosive).

The most common type of regulator failure is the internal leak, sometimes called creep or crawl. This can occur when the seat becomes damaged or displaced due to a foreign particle such as a metal chip or other material. When the seat cannot close completely, delivery pressure will not be maintained, and regulator pressure cannot reach a state of equilibrium. Downstream or delivery pressure will continue to climb until the safety relief mechanism on the regulator is activated (usually a relief valve or a diaphragm burst disk). Checking for this type of failure is relatively easy if the device has a gauge that reads regulated pressure. The gauge pressure will start to rise above the set point and continue upward. This creates a potentially hazardous condition where any downstream equipment would be subjected to pressures beyond the rated limit. Regulators should be visually checked for this type of failure. Excessive flexing of metal regulator diaphragms can cause a radial crack, which allows gas to escape to the atmosphere through the vent hole in the bonnet.

8.3 Piping and Manifolds

Piping, tubing, valves and fittings conveying hazardous materials shall be designed and installed in accordance with ASME B31⁴³.

The system’s weakest component determines the overall pressure limit.

8.4 Toxic Gases

*ACG = Any commercial grade

Quantities in each building must be managed below the Threshold of Consequence or MAQ, whichever threshold is lower.

8.9 Quantity Limits on the Evanston Campus

The scope of this section generally applies to areas constructed for business occupancy (B). For quantity limits for all other occupancies, especially High Hazard Group (H) contact Research Safety.

The regulations for the Evanston Campus differ from the regulations on the Chicago Campus.

The building users on the Evanston Campus generally have to comply with the limits according to the International Building Code (IBC) and the International Fire Code (IFC). Groups of research laboratories within a building may be subdivided into fire control areas. For more specific information regarding laboratory design and fire control specification contact Facilities Management.

The total quantities of flammable or combustible liquids allowed in a fire control area (laboratory or suite of laboratories) are limited by the location in the building and the construction specifications.

 Reference: International Fire Code (IFC) 2021 Excerpt from Tables 3806.2.1 and 5003.1.1(2)

8.9.1 Quantity Limits on the Chicago Campus

Note that the McGaw/Olson building is classified as institutional occupancy NOT business occupancy, which limits the storage quantities in accordance with NFPA 99. Contact Research Safety for further information.

Maximum Size and Quantity Limitations for Compressed or Liquefied Gas Cylinders in Laboratories Located in Buildings Classified Business Occupancy 

Reference: 2019 NFPA 45

8.10 Glossary

Bulk systems

• Assembly of storage containers, pressure regulators, PRDs, vaporizers manifolds, and interconnecting piping that has a storage capacity of more than 20,000 scf (566m3) of compressed gas or cryogenic fluid including unconnected reserves regardless of storage pressure. A bulk system terminates at the point where gas at service pressure enters the supply line. (Reference: CGA P-18 2006).

Control area

• Each building’s floor has one or more control areas. This term is used in conjunction with Maximum Allowable Quantities and is further defined in the International Fire Code. A record of control area boundaries is maintained by Facilities.

Cylinder parts

1. Cylinder valve-protection cap
2. Valve hand wheel
3. Retainer and valve stem packing nut
4. Over pressure relief/safety device
5. Valve outlet connection: Standardized CGA outlet (i.e., No. 350 for hydrogen service) to prevent interchange of equipment with incompatible gases
6. Cylinder collar
7. Valve outlet cap
8. DOT identification, cylinder material, service pressure
9. Cylinder serial number
10. Month/Year hydrostatic test
11. Other identification markings

Cylinder dimensions

Emergency alarm system

• A system to provide indication and warning of emergency situations involving hazardous materials.

Excess flow control

• A fail-safe system or other approved means designed to shut off flow caused by a rupture in pressurized piping systems.

Labels

• Under the Globally Harmonized System (GHS), chemical manufacturers, distributors, and importers are required to use labels that include the following: product identifier, signal word, pictogram, hazard statement, precautionary statement, and supplier information. For example:

Maximum Allowable Quantity (MAQ)

• The term is further defined in the Appendix and by the International Fire Code. A record of MAQs per control zone is maintained by Research Safety.

Oxygen deficient atmosphere

• An atmosphere in which the oxygen concentration is less than 19.5% by volume.

Permissible exposure limit (PEL)

• The allowable OSHA limit for an air contaminant in which workers may be exposed day after day without adverse health effects.

Standard cubic foot (scf)

• Cubic foot of gas measured at 70°F (21.1 °C) and 14.7 psia (101.3 kPa abs).

Restricted commodity

• Restricted in this context means that special licenses or permits are required from a federal agency before the item is allowed on campus or for a gas to exceed a threshold quantity.

Toxic gas and highly toxic gas

• A toxic gas is one with a median lethal concentration (LC50) of more than 200 and less than 2,000 parts per million by volume of gas or vapor when administered by inhalation for an hour (or less if death occurs within one hour) to albino rats weighing between 200 and 300 grams each. A highly toxic gas is characterized by a median LC50 of 200 ppm or less under the same conditions. (Reference: IFC 2012 – Chapter 2)

Sources:

Most personal safety aspects for field research activities including training, insurance, safety advisories, trip registry, immunizations, and emergency planning checklist are addressed by Global Safety and Security.

There are restrictions about transporting hazardous materials domestically and internationally. Services for shipping of hazardous chemicals, radioactive materials and other restricted commodity off campus require some preplanning for compliance. Bringing potentially infectious research materials from field research activities onto campus also requires preplanning.

Removing restricted commodity and Class 4 lasers from campus without notification of researchsafety@northwestern.edu is prohibited.

Northwestern University employees officially sponsored to perform hazardous field research activities off campus should notify researchsafety@northwestern.edu.

The Export Compliance & International Compliance (ECIC) team assist in navigating the regulations on export controls. Heed federal export restrictions that regulate the distribution of technology, services and information.

1. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011, pg. 267

2. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011, pgs 270-272

3. OSHA Laboratory Standard

4. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011 pgs. 40-41

5.  Excerpts from Prudent Practices in the Laboratory, National Research Council 2011, pg. 34, 149

6. Exerpts from Prudent Practices in the Laboratory, National Research Council 2010, pgs. 137-138

7. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011 pgs. 111-112

8.  Excerpted from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 74, 133, 140, 153, 174-175 

9. Labware Chemical Resistance Table, Thermo Scientific

10. Excerpted from Prudent Practices in the Laboratory, National Research Council 2011, pg. 75, 109 

11. Excerpted from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 75, 76, 159

12. Excerpted from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 75, 76, 159

13. American Chemical Society, “Creating Safety Cultures in Academic Institutions” (2012) and “Identifying and Evaluating Hazards in Research Laboratories” (2015)

14. Reagent Chemicals, MCB Manufacturing Chemists, Inc., 1981, pp. 359-402. 

15. OSHA Laboratory Standard 

16. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011, pg. 97

17. NFPA 45 – Standard for Laboratories Using Chemicals – Chapter 10 Flammable and Combustible Liquids

18. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011, pg. 70, 140, 191 

19. 2012 International Fire Code 5003.9.8 

20.  Excerpted from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 72, 159-161 

21. Excerpt from Prudent Practices in the Laboratory, National Research Council 2011, pg. 156 

22. Chemical Reactivity Assessments in R&D, David Leggett, PhD, CChem, MRSC 

23. Excerpt from Prudent Practices in the Laboratory, National Research Council 2011, pg. 158 

24. Excerpt from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 173-174

25. Parr No.230M Safety in the Operation of Laboratory Reactors and Pressure Vessels

26. Pressure Classification of Reactions, NFPA 45 Standard on Fire Protection for Laboratories Using Chemicals (2011 Edition) Annex C 45-39

27. Excerpt from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 175 

28. Excerpt from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 175 

29. Source: The Rotary Evaporator

30. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 172-173

31. 2012 International Fire Code 5003.9.8 

32. Reference: 15-24-310 Municipal Code of Chicago – Flammable Liquids ARTICLE III. CLOSED CONTAINER STORAGE General requirements 

33. Chemical Reactivity Assessments in R&D, David Leggett, PhD, CChem, MRSC 

34. 2011 NFPA 45 10.3.3

35. The DOW Chemical Company, Lab Safety Academy 2014

36. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011, pg. 72 

37. Excerpts from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 72, 100, 133 

38. From note in Organic Syntheses, 2011

39. A chemical that will ignite spontaneously in air at a temperature of 130F (54.4C) or below.

40. The definition is adopted from the US Department of Energy Notice N456.1 – THE SAFE HANDLING OF UNBOUND ENGINEERED NANOPARTICLES, Approved 01/05/09

41. The definition is adopted from the US Department of Energy Notice N456.1 – THE SAFE HANDLING OF UNBOUND ENGINEERED NANOPARTICLES, Approved 01/05/09

42. The definition is adapted from the Centers for Disease Prevention and Control (CDC) universal precautions designed to prevent transmission of bloodborne pathogens in the work place.

43.IFC 2012-5003.2.2

44. IFC 2012-Section 6004.1.2

45. IFC 2012-6004.1.2

46. IFC 2012-Section 6003.1.3 Treatment Systems

47. IFC 2012-6004.2.2.10

48. IFC 2012-5003.1.4

49. Not a CFATS regulated gas

50. 2015 NFPA 45 Table 9.1.1

51. Excerpt from Prudent Practices in the Laboratory, National Research Council 2011, pgs. 256ff