Lab Safety Manual: Laboratory Use/Procedures and Policies


rev 9/2014

This Section outlines general safety procedures and policies that apply to all laboratory work.  The Safety Committee may establish additional requirements to address potential hazards that could result from specific operations.

Given the diversity of laboratory operations, this Manual does not include specific information about all potential laboratory hazards. Faculty members are relied upon to use their best judgment in identifying hazards in their laboratory. Additionally, given the generic nature of some of the policies and procedures of this Manual, there may be situations where alternative procedures would provide a greater level of safety. If a faculty member believes that an alternative procedure would provide a greater level of safety, the Safety Committee must be contacted for clarification and permission.

The attitude of those working in the laboratory is one of the most important factors in the safe conduct of laboratory experiments.  All stages of an investigation, from design through completion, must consider safety as a guiding principle.  The key to designing and carrying out safe laboratory experiments is knowledge of the potential hazards.  It is the responsibility of each individual working in the laboratory to become thoroughly familiar with the hazards of the chemicals they are using and the operations they are performing.

4.1 Controlling Sources of Exposure

All experiments must be designed and carried out to minimize hazardous chemical exposure. Source reduction, engineering controls, and protective equipment, in that order, are the three primary means of controlling exposure. The following are examples of source reduction and engineering control techniques.

Source Reduction

  • Use the least hazardous chemical that will serve the intended purpose.
  • Design experiments to use the minimum amount of hazardous chemicals required.
  • Always close containers when not in use.
  • Minimize the surface area of open containers (e.g. use of flask vs. beaker).

Engineering Controls

  • Use fume hoods whenever possible.
  • Do not use fume hoods for long term storage of equipment or chemicals.
  • Avoid the release of hazardous chemicals in rooms with no ventilation system or with re-circulating air systems.
  • Use equipment and glassware only for their designed purposes. Never use damaged equipment or glassware.
  • If operations must be left unattended, provide for containment of hazardous chemicals in the event of equipment failure.

Protective Equipment

Minimum levels of protective equipment are described in Section 4.5. However, it should be recognized that source reduction and engineering controls are generally more effective means of exposure control. 

4.2 Personal Hygiene

In the laboratory, good personal hygiene practices are essential to minimize hazardous chemical exposure and potential injury from other hazardous conditions, such as broken glass.

  • The storage or consumption of food or beverages, application of make-up, and smoking are prohibited in all laboratory areas and hazardous chemical storage areas.
  • Avoid "routine" exposures.  Do not taste and avoid smelling any hazardous chemicals.  Never mouth pipette.
  • Wash hands immediately upon contamination, after handling hazardous chemicals, and before leaving the laboratory.
  • Long hair and loose clothing must be confined when working in the laboratory.
  • A soiled or contaminated lab coat should be placed in a plastic bag and exchanged for a clean one; contact the Lab Manager.
  • Shoes must be worn at all times in Cole Science Center.  
  • Closed-toe shoes must be worn when working with hazardous chemicals, biological materials, or when moving heavy objects.  Sandals or perforated shoes are not acceptable, as feet are not protected from spills or falling objects. 
  • Please note that even if you are not actively working on a project yourself but are inside the lab, you are still at risk from the activities of others around you.  Therefore, all safety precautions still apply.

4.3 Housekeeping

Keeping the laboratory work area organized and clean is important to the safe handling of hazardous chemicals.  Only the equipment and chemicals necessary for the particular procedure being performed should be in the work area.  This is particularly important when working in a fume hood, as storage of numerous containers or pieces of equipment can severely diminish the  hood's effectiveness. If several people are working in the same laboratory,  space and hood requirements access should be discussed and work areas agreed upon.

Floors and surfaces should be kept clean and spills cleaned up immediately as described in Section 2.  The entire work area should be cleaned at the end of each day.

4.3.1 Lab Project Termination

When a lab project is completed, will cease to be active for a period of time, or the faculty member or student leaves Hampshire College, clean-up must be done by the faculty member and student, and approved by the Lab Manager.  Clean up includes:

  • remove and properly dispose of all hazardous materials from the laboratory or project area, and any shared storage units, refrigerators, stock rooms, chemical cabinets, and waste collection areas
  • clean and decontaminate all laboratory equipment, hoods, bench tops, cabinets, and shelves

These procedures are intended to reduce the number of unidentified and unwanted hazardous materials and wastes in the laboratory, thereby reducing disposal costs, and providing a clean and safe lab for work. 

The Lab Manager inspects for proper clean-up and handling of hazardous materials and will notify the Dean of Natural Science if proper clean-up, disposal, and decontamination procedures have been followed, and the faculty and their student have fulfilled responsibilities for cleanup.

Any problems resulting from improper management or clean up of hazardous materials at close-out will be addressed by the Dean of Natural Science, and if necessary, the Dean of Faculty or Dean of Students.

4.4 Pets in the Laboratory

Pets are not allowed in the laboratory.

4.5 Unattended Operations

Avoid leaving operations unattended. When it is necessary to leave an experiment unattended, provide for containment of hazardous chemicals in the event of equipment failure. Additionally, leave the lights on and place a warning sign on the door if, in the event of an emergency, there exists a hazard to persons entering the room.

4.6  Safety Data Sheets and Lab Safety Information

The OSHA Laboratory Standard defines a "hazardous chemical" as one that exhibits physical or health hazards.

"Physical Hazard" - a chemical for which there is scientifically valid evidence that it is a combustible liquid, a compressed gas, explosive, flammable, an organic peroxide, an oxidizer, pyrophoric, unstable (reactive), or water reactive.
"Health Hazard" - a chemical for which there is statistically significant evidence based on at least one study conducted in accordance with established scientific principles that acute or chronic health effects may occur...includes...carcinogens, toxic or highly toxic agents, reproductive toxins, irritants, corrosives, sensitizers, hepatotoxins, nephrotoxins, neurotoxins, agents which act on the hematopoietic (blood) system, and agents which damage the lung, skin, eyes, or mucous membranes.

Determining the hazard of a chemical is the responsibility of the manufacturer of the chemical. Information on the hazards of a particular chemical can be found on the label, the manufacturer's Safety Data Sheet (SDS), and in reference publications listed in the Bibliography.
Safety Data Sheets received from the manufacturer are available to all users of the CSC.
SDS contains detailed chemical information including:

  • the contents of a given product
  • physical, chemical, and toxicological hazards associated with that material
  • appropriate personal protective equipment and clothing necessary (e.g., appropriate type of gloves, goggles)
  • safe handling and disposal guidelines
  • emergency procedures, including care and contact personnel  (e.g., poison contact)

SDS for CSC materials are located in an online library available through a link on The Hub. A fact sheet on how to read a SDS is included in Appendix 4-A.
There are several systems for categorizing the severity of chemical hazards. It is important to recognize the similarities and differences of those systems. Two common systems, the Global Harmonization System (required on SDS) and National Fire Protection Association Hazard Identification System, are described in Appendix 4-B.

4.7 Chemical Inventory, Transport, and Shipping

All chemicals must be included in the CSC chemical inventory.  When a new chemical is received it must be tagged and entered into the inventory by the faculty member or Lab Manager.  When containers are emptied or the chemical disposed of, the date must be entered into the inventory.  When chemicals are moved from one storage location to another, the location on the inventory must be updated.  Chemicals taken from a storage area for temporary use in the laboratory do not need to change the  location.

A bottle carrier or cart must be used when moving any quantity of an acute toxin and 1 liter or greater containers of flammables or concentrated acids or bases from the stockroom to the laboratory or between laboratories. A bottle carrier or cart is recommended when moving other chemicals from the stockroom to the laboratory and between laboratories.

All shipments of hazardous materials (e.g. chemicals, biological materials) from Hampshire College to other locations must comply with all Department of Transportation (DOT) and International Air Transport Association (IATA) requirements. The Laboratory Manager must notify the Chemical Hygiene Officer before shipping chemicals and hazardous materials.  All chemical and hazardous materials shipments must be approved to ensure that materials are packaged and labeled properly and that the proper documentation accompanies the shipment.  The Laboratory Manager is responsible for forwarding all records pertaining to shipments to the Chemical Hygiene Officer. 

4.8 Personal Protective Equipment

Protective equipment must be worn to guard against injury from routine or accidental events. Each faculty or supervising staff member is responsible for choosing appropriate protective equipment for their staff and students. The following personal protective equipment is available for persons working in the laboratory. Know what equipment is necessary for your work.

4.8.1 Eye and Face Protection

The hazards of each laboratory operation must be identified and the approved eyewear worn. Eye protection meeting ANSI Standard Z87.1, as summarized in Table 4-1 below, is the minimum level of eye protection required. 

Table 4-1 - Summary of ANSI Z87.1-98
Approved Protective Eyewear

IMPACT: flying objects, fragments, particles 1,2,3,4,5,6
HEAT: hot sparks 1,2,3.4,5,6
HEAT: high temperature 1,2,3,5,6
CHEMICAL: splash 3,4, or 5(with 3 or 4)
CHEMICAL: irritating mists 4
DUSTS: airborne particles 3,4,6
IR/UV RADIATION: welding, soldering, brazing, cutting Refer to ANSI Z87.1-89
1. Safety spectacles, with side shields
2. Goggles, flexible fit, regular ventilation
3. Goggles, flexible fit, hooded ventilation
4. Goggles, rigid body, cushioned fit
5. Face shield, plastic window
6. Chipping goggles, eyecup type

Wearing contact lenses is highly discouraged when working with or near chemicals, particularly solvents. Operations Requiring Chemical Splash Goggles

To protect students, faculty, staff, and visitors from chemical eye hazards, the following operations require chemical splash goggles. When these operations are conducted in a fume hood with the sash lowered, safety glasses are acceptable.

  1. Use of strong acids or bases (outside pH range of 2 - 10).
  2. Use of corrosive gases.
  3. Use of potentially explosive or water reactive chemicals (as defined in Section  5.3).
  4. Use of acutely toxic chemicals (as defined in Section 5.6) in liquid or powder form.
  5. Use of cryogenic liquids when there is a risk of pressure buildup or splash or particle hazard.
  6. Use of other hazardous chemicals in liquid form.
  7. Any activity when there is an explosion or implosion hazard.

Goggles must be worn by the person whose activity causes the hazard and by adjacent individuals. Faculty, staff, teaching assistants, and visitors working with students who are required to wear splash goggles must also wear splash goggles. Faculty are responsible for identifying any additional laboratory operations in their laboratories that pose a splash hazard and  require splash goggles.

Chemical splash goggles are available in boxes marked "goggles" located throughout the lab areas. These goggles meet the American National Standards Institute Z87.1 standards (1998). Face shields are also available for additional protection; chemical splash goggles must be worn under face shields. Operations Requiring Safety Glasses or Splash Goggles

The following operations require the use of safety glasses or splash goggles.

  1. Operations using or generating liquid or fine particulate chemicals for which splash goggles are not required.
  2. Chipping, cutting, and grinding activities.
  3. UV and/or IR protective safety glasses are required when working with instruments generating and releasing UV or IR emissions unless a safety mechanism automatically shuts off the emission source when exposure is possible. Refer to ANSI Z87.1-89.
  4. When installing or removing regulators on gas cylinders. 

4.8.2 Gloves

The need to wear gloves, and the selection of the appropriate gloves, depends on the hazard of the chemical, the potential for contamination during the experiment, and dexterity requirements. It is the responsibility of the faculty to choose the appropriate gloves for their staff and students.

Proper glove selection is a function of the specific chemical resistance of the material as measured by permeation rate and breakthrough time. Disposable latex gloves have limited resistance to most commonly used hazardous laboratory chemicals. They should not be used without investigating their resistance to the chemicals being used, or in operations where contamination is anticipated. When contaminated, they must be removed immediately, and the hands washed. The use of latex gloves also poses a risk of serious allergic symptoms in sensitive individuals and other individuals developing a latex allergy.

More resistant gloves include natural rubber, neoprene, nitrile, butyl, Viton, and polyvinyl chloride. Nitrile gloves are available in the stockroom; other gloves should be ordered as needed.

Recommendations of the glove manufacturer and the material safety data sheet for the particular hazardous chemical should be used in choosing the appropriate glove.

Best Manufacturing Company 
Ansell Occupational Health Care 
Oklahoma State University

4.8.3 Clothing

The purpose of protective clothing is to prevent skin contamination and to prevent the carrying of contaminants outside the laboratory. Street clothes may afford limited skin protection but may result in contaminants being carried outside the laboratory. Bulky or dangling attire and easily combustible clothing should not be worn in the lab. 

Protective Clothing: The use of a lab coat is strongly recommended in all laboratories. Lab coats must be worn in the laboratory when handling:

  • any quantity of select carcinogens (see 5.8) or reproductive toxins (see 5.7) that are absorbed through the skin
  • any quantity of acute toxins (see 5.6). 
  • greater than 25 mL of strong acids or bases (outside pH range 2 - 10)

Lab coats are available from the lab manager. A soiled or contaminated lab coat should be placed in a plastic bag and exchanged for a clean one; contact the lab manager. 

All protective clothing should be removed before leaving the lab area to keep potential contamination restricted to the lab area. 

Additional specialized protective clothing should also be used in certain high hazard operations: for example, when using hydrofluoric acid (see Section 5.2.4). Again, it is the responsibility of the faculty to choose the appropriate protective equipment for their staff and students.

Protective Footwear: Shoes must be worn at all times in Cole Science Center. When working with hazardous chemical or biological materials, or moving heavy objects, closed-toe shoes must be worn. Sandals or perforated shoes are not acceptable, as feet are not protected from spills or falling objects. 

4.9 Hoods

There are several different types of hoods in Cole Science Center. Each of these is discussed briefly below.  The appropriate hood must be used. Use of the wrong type of hood could increase the potential hazard. All hoods are tested annually to verify proper performance.

4.9.1 General Use Fume Hoods

These hoods, which are designed to protect the user, are appropriate for working with flammables, acids, bases, and organic solvents; they should be operated with the sash lowered to the indicated point (red arrow).  Working with the sash lowered to this point creates the necessary draw (air flow into the hood), and adds protection from splashes or explosions. 

1. Before using a fume hood observe the following precautions.

  • Remove any bulky items in the hood as these will prevent proper airflow.
  • Turn the hood on and confirm that the hood is drawing air (a tissue or kimwipe held at the opening should be gently pulled into the hood area).
  • Do not store chemicals in the hoods, or remove stored chemicals before use.

2. When using a fume hood observe the following precautions.

  • Do not keep unnecessary materials in the hood. 
  • Chemicals or waste stored in a hood must be in secondary containment.
  • Use only intrinsically safe (i.e., explosion proof) equipment when working with flammables. (Intrinsically safe equipment is available from the Lab Manager.)
  • Keep all materials back at least 6 inches inside the hood.  The sash should be able to be fully closed in the event of an emergency.  
  • Work with the sash lowered to the indicated level (red arrows) for proper venting.
  • Be aware of air disturbances (from opening doors, fans, passers by, etc.), as these will affect the draw of air into the hood.
  • Do not attach signs or materials to the sash as these prevent visibility into the hood and safe operation of the sash. 
  • Clean up spills immediately.   Ask the instructor or Lab Manager for the appropriate way to do this, as some materials must be treated first (e.g., acids and bases must be neutralized).

4.9.2 Laminar Flow Hoods and Biological Safety Cabinets

Laminar Flow hoods are used to protect microbiological work from contamination; they contain no UV lamp source.  These are also called clean benches, and are used for work with non-hazardous materials when very clean environments are needed for high purity work.  The operator sits downstream of the materials and airflow; therefore, toxic, infectious and hazardous materials should never be used in laminar flow hoods.

Biological safety cabinets (a.k.a. tissue culture hoods) are used for hazardous microbiological work such as work with pathogens; they are designed to protect the person, the product, and the environment for operations requiring Biosafety Level 1 and 2, such as tissue culture analysis and bacteriological or virological applications.   These hoods contain an ultraviolet lamp source and HEPA filters which are 99.9% efficient for particles of size
0.03 um.

These types of hoods do not protect the user from hazardous vapors.  At this time, Hampshire does not have a hood that  protects from chemical vapors while providing a sterile hood environment.

4.10 Electrical Safety

The voltage and current used in laboratories are potentially lethal.  The Lab Manager should be notified if unsafe electrical situations exist (e.g., wires are strung across pathways, frayed wires are found, grounding plugs have been removed), or if equipment malfunctions. 

Instruments are serviced regularly following the manufacturer’s guidelines.  Instruments that are out of service should be “locked-out”.  Lockout prevents equipment from being turned on or operated while being repaired or inspected; equipment cannot be restarted until repairs are complete and the lockout removed.  Only trained individuals should perform equipment repair or modification.

4.10.1 Electrophoresis Safety

Electrophoresis is a lab technique that presents a potential hazard as the user manipulates wires with high voltage.  When working with electrophoresis, the following precautions must always be followed:

  • the bench and floor in the area should be dry
  • the high voltage leads should be intact, the connections secure, and no plugs should be exposed
  • all electrophoresis chambers should be covered when in use
  • all power supplies should be turned to zero voltage and current after use, and all leads should be unplugged from the unit (power supplies have internal capacitance that stores electrical charge even after the units are turned off, and accidental discharge can be fatal)
  • use only one hand to plug and unplug high voltage leads, do not put the other hand in a position that will ground you, resulting in a potentially lethal shock across the chest
  • do not operate an electrophoresis system without appropriate supervision and a buddy present

4.11 Machine Tools

The use of stationary machine tools and powered hand tools is subject to the following requirements.

  1. Use of machine tools and power hand tools must be done under the instruction and direct supervision of a faculty or staff member familiar with the hazards and appropriate safeguards for the tool being used.
  2. All machine tools must be stored in a locked area or locked out when a supervising faculty or staff member is not present.
  3. Choose the right tool for the job.  Makeshift or undersized tools are always a hazard.
  4. Eye protection must be worn at all times.  Safety glasses with side shields meeting ANSI Standard Z87.1-89 are the minimum level of protection.  Goggles may be advisable under certain situations.
  5. Be sure all safeguards are in place and working before starting work.  Guards, as supplied by the manufacturer, must be used when operating equipment. Fabricated tools guards must meet OSHA requirements.
  6. Check portable power tools for poor wiring or loose switches.  Do not use a tool with a frayed cord or with the grounding prong removed.
  7. Chuck keys, calipers, gauges, and other tools should be removed immediately after use.  Forgetting to do so may lead to the tool becoming a projectile when the machine is started.
  8. Never wear gloves, wristwatches, rings, bracelets, or other jewelry while operating machinery.  Long hair and loose clothing should be controlled near operating machinery.  Rags, drawings, hand tools, lubricant containers, and other loose objects should be kept away from moving machine parts and machine surfaces that may vibrate during machine operation. 
  9. Use a vise or clamps to secure the work when possible. 
  10. When using portable tools do not overreach.  Keep a good balance and proper footing at all times.
  11. Be aware of potential hazards in your work area.  Don't overlook the hazards and workspace requirements of others working nearby.  When operating power tools in a strange environment check for flammable liquids, combustible materials, and other hazards before beginning work.
  12. Keep out of the way of things that may be thrown by machinery.  Some machines produce large amounts of debris.  Debris not caught by the machine's dust collection system may be propelled out of the machine in a particular direction and distract or obstruct operator's vision. Some machines may also eject stock material under some circumstances.  Table saws and wood jointers, for example, will eject wood stock in the direction of the rotation of the blade if the material is improperly fed.  These machines should be operated from one side, minimizing any possible hazards.
  13. Chips and debris should be cleaned with a brush and not with compressed air or by hand.
  14. Machining of pyrophoric metals (such as magnesium) or toxic metals (such as beryllium, cadmium, lead, and osmium) requires special precautions.  Any work on these types of materials requires approval from the Safety Office.
  15. Do not remove stock or reach near any moving parts of a machine until those parts have come to a complete stop.  Turning the machine "off" does not immediately halt the hazardous motion of many machines. 
  16. Machine adjustments or lubricating may be done while the machine is operating only if no safeguards are removed or bypassed and only if the operator is not exposed to any hazardous energy.
  17. Repair and servicing must be done in accordance with the Hampshire College Lockout/Tagout Program.

Appendix 4-A: How to read an MSDS

Appendix 4-B: Labeling and Ranking Standards