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.
Personal hygiene is extremely important to persons working in a laboratory. Contamination of food, beverages, or smoking materials is a potential route to exposure to toxic chemicals 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 familiar elementary safety rule shall be followed by everyone working in or visiting a laboratory.
Hand washing is a primary safeguard against inadvertent exposure to toxic chemicals or biological agents. Always wash your hands before leaving the laboratory, even though you use gloves. Wash your hands after removing soiled protective clothing, before leaving the laboratory, 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.
Personal protective clothing and equipment protects you from injury due to absorbing, inhaling, or coming into physical contact with hazardous materials. Some protection is afforded by ordinary clothing and eyeglasses. You have a responsibility to dress sensibly for laboratory work. Laboratory clothing protects workers' own clothing. 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 respirate. Select garments and fabric based on the nature of the hazardous agent.
Confine long hair and loose clothing when in the laboratory to keep them from catching fire, dipping into chemicals, or becoming entangled in moving machinery. Avoid wearing finger rings and wrist watches which may become contaminated, react with chemicals, or be caught in the moving parts of equipment.
Personal protective clothing and equipment shall be used and maintained in a sanitary and reliable condition and shall be cleaned regularly to avoid spreading contamination. Non-contaminated laboratory coats can be cleaned by any laundry service/dry cleaner. Contaminated coats should be sent to the University approved vendor.
Remove laboratory coats and gloves before you leave the laboratory to prevent spreading contamination to other areas. Keep a clean spare coat to wear outside the laboratory. Do not wear gloves outside the laboratory.
Laboratory coats shall never be washed at home. Regular clothing that is suspected of being contaminated shall be evaluated for proper decontamination or disposal method. It shall not be washed with or come into contact with other personal laundry.
Cover unprotected skin whenever possible. Suitable clothing shall be worn in the laboratory; 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. Wool affords more protection from flash burns or corrosive chemicals than cotton or synthetic fabrics. 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 leather shoes in the laboratory 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 are 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 splashes and spills, vap, 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.
Eye protection is mandatory in laboratories because of the obvious hazards of flying objects, splashing chemicals, and corrosive vap. 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. Regulations require that persons whose vision requires corrective lenses, and who are required to wear eye protection, shall wear goggles over their eyeglasses, prescription safety glasses, or goggles with prescription lenses. These options are also recommended for persons who customarily wear contact lenses. If contact lenses are worn, they should not be handled in the laboratory and shall be worn with regularly required eye protection, such as plastic goggles.
Gloves are worn to prevent contact with toxic or biological agents, burns from hot or extremely cold surfaces or corrosives, or cuts from sharp objects. Skin contact is a source of exposure to infectious agents and toxic chemicals, including carcinogens. Many gloves are made for specific uses. For adequate protection, select the correct glove for the hazard in question.
A leather glove provides good protection for picking up broken glass, handling objects with sharp edges, and inserting glass tubing into stoppers. However, because they absorb liquid, leather gloves do not provide protection from chemicals, nor are they adequate for handling extremely hot surfaces. Gloves designed to insulate against hot surfaces and dry ice are not suitable for handling chemicals.
Inspect gloves for punctures or tears before putting them on. To prevent contamination of your hands or work surfaces, wash rubber or plastic gloves thoroughly with water before removing them. Pull off disposable gloves inside out and dispose of them according to the contamination hazard. Always remove contaminated gloves before leaving the laboratory. Always wash your hands after removing gloves, before leaving the work area, and before eating, drinking, smoking, or applying cosmetics.
The chemical resistance of rubber or plastic gloves varies greatly according to the glove material and the chemical handled. Consult for information before selecting and using laboratory gloves or see the sources listed below.
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. Call the manufacturer to verify that a particular glove material is suitable for the chemical in use.
In practice, most labs tend to rely on latex as the staple for glove supplies for general laboratory use. Due to the prevalence of allergies to natural latex proteins, policy recommends substitution of latex gloves with nitrile or neoprene ones. Although these alternate glove materials may vary from latex in the range of typical lab chemicals to which they are rated as resistant, they do exhibit longer breakthrough times.
Keeping things clean and organized helps provide a safer laboratory. Keep drawers and cabinets 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 in a wastepaper basket separate from chemical wastes. Broken glass and other sharp items shall be disposed of in rigid, puncture-resistant containers to protect persons collecting the waste materials. Needles and syringes that are not contaminated may be sealed in a rigid, puncture-resistant container and placed in a regular waste receptacle. When discarding empty boxes or other containers bearing hazardous materials labels, the labels shall be defaced or removed before disposal. Contaminated boxes or containers shall not be disposed of in the regular trash.
Chemical wastes and unwanted chemicals shall be disposed of promptly and not left to clutter a laboratory.
When cleaning laboratory glassware, wear appropriate gloves that have been checked for tears or holes. Avoid accumulating too many articles in the cleanup area around the sink; space is usually limited, and piling up glassware leads to breakage. Do not clean food containers in a sink that is used for cleaning contaminated glassware. Acids and solvents shall not be rinsed down the drain during cleaning but shall be collected for proper treatment and disposal.
A personal vehicle shall not be used to transport 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 or by air or water. DOT also requires that all individuals offering a hazardous material for transport receive training. The material to be shipped shall be properly packaged in accordance with all applicable regulations and appropriate shipping papers shall be provided.
Biological materials shall be shipped in compliance with DOT and Centers for Disease Control and Prevention regulations. Transport of regulated plant or animal pathogens shall comply with U.S. Department of Agriculture and Illinois Department of Agriculture regulations.
Do not allow visitors, including children and pets, in laboratories 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 laboratories for legitimate academic and research purposes. Each individual working in a laboratory should prudently evaluate the risks to visit, especially to persons of increased risk such as children and immunosuppressed individuals.
Laboratories shall be provided with general ventilation adequate for employee comfort and sufficient to supply air for chemical fume hoods and other local ventilation devices. Because the general air supply is not adequate for manipulating hazardous materials on an open lab bench, volatile or toxic chemicals shall be handled in a chemical fume hood or other appropriate containment device.
A chemical fume hood is an important engineering control for preventing exposure to hazardous materials. In conjunction with sound laboratory techniques, a chemical fume hood serves as an effective means for capturing toxic, carcinogenic, offensive, or flammable vap or other airborne contaminants that would otherwise enter the general laboratory atmosphere. With the sash lowered, the chemical fume hood also forms a physical barrier to protect workers from hazards such as chemical splashes or sprays, fires, and minor explosions. Chemical fume hoods may also provide effective containment for accidental spills of chemicals, although this is not their primary purpose. The deliberate release and venting of chemicals (i.e., evaporation) in chemical fume hoods shall never be used as a means of disposal.
Safety showers shall be installed in all areas where employees may be exposed to splashes or spills of materials that may be injurious to the eyes and body. As a general rule, new shower installations shall adhere to the recommendations for shower location and minimum performance requirements established in American National Standard Z-358.1 (1998). Showers shall be placed as close to the hazard as possible, but in no case more than 10 seconds' travel time from the hazard. Department heads shall ensure that safety showers are installed in the department where needed.
An eyewash providing a continuous, low-pressure stream of aerated water shall be provided in each laboratory in which chemical or biological agents are used or stored and in laboratories where nonhuman primates are handled. The eyewash shall be easily accessible from any part of the laboratory. If possible, the eyewash should be located near the safety shower so that, if necessary, the eyes can be washed while the body is showered.
This kit shall not be shared between lab groups. The kit should be stored in the main lab and be easily accessible to any other lab locations that belong to a particular group. The first aid kit should contain the items recommended in the First Aid Kit Policy and Guidelines for Laboratories. It shall be inspected monthly to ensure that no items are missing and that none of the remedies (e.g., saline solution, ointment) in the kit have expired. The inspections shall be documented (an inspection record is included in the policy).
Every laboratory using chemical or biological agents shall have at least one sink, preferably located near the room exit, available for hand washing. The sink shall be cleaned regularly to eliminate contamination, and soap shall be supplied for hand washing.
Drain traps in sinks, flow, and other places will dry out if they are not used regularly, allowing contamination to back up into the room. Drain traps shall be kept filled with water to prevent backup. Also fill cup sinks on benches and in chemical fume hoods.
Electrical currents of very low amperage and voltage may result in fatal shock under certain circumstances. Voltages as low as 24 volts AC can be dangerous and present a lethal threat. Low-voltage DC circuits do not normally present a hazard to human life, although severe burns are possible. The duration of contact with a live circuit affects the degree of damage, especially with regard to burns.
All electrical switches shall be labeled, including circuit breakers in the service panels, and all laboratory personnel shall know where these controls are and how to shut off circuits or equipment in case of fire or other accident. Any electrical equipment that is not operating properly or seems to be overheating shall be turned off immediately and inspected by a qualified technician.
Electrical equipment should be inspected periodically to confirm that the cords and plugs are in safe condition. Circuit diagrams, operating instructions, descriptions of hazards, and safety devices are usually provided by the manufacturer and should be kept on file for reference.
Place electrical equipment so as to minimize the possibility that water or chemicals could spill on it or that water could condense and enter the motor or controls. In particular, place such equipment away from safety showers. In cold rooms, condensation can be minimized by mounting electrical equipment on walls or vertical panels.
If a worker receives an electrical shock and is in contact with the energized device, use nonconductive gloves or a nonconducting device to pull or push the victim free from the electrical source. Help victims only if you are certain that you will not endanger your own safety. Turn off or disconnect the power source if possible. Call 911. If a trained person is available, start CPR if necessary. Get medical assistance at once.
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 vap are present. Static electricity is increased by 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 nonconducting hoses; high-pressure gas cylinders upon discharge; and clothing or containers made of plastic or synthetic materials.
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 rot shall be balanced each time they are used. Securely anchor and shield each unit against flying rot. Regularly clean rot and buckets with noncorrosive 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.
If vacuum pumps are used with volatile substances, the input line to the pump shall be fitted with a cold trap to minimize the amount of volatiles that enter the pump and dissolve in the pump oil. The exhaust from evacuation of volatile, toxic, or corrosive materials shall be vented to an air exhaust system. A scrubber or trap may also be required. If pump oil becomes contaminated with toxic chemicals, it will exhaust the chemicals into the room air during future use.
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.
Syringes used with hazardous agents shall have needle-locking or equivalent tips to assure that the needles cannot separate during use. Do not recap 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.
Facility maintenance and custodial staff shall not handle or remove hazardous waste bags or other containers.
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 it can be damaged in shipping, handling, or storage, inspect glassware 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, it can be examined in polarized light for strains.
Operations that may generate airborne contaminants or that use flammable liquids or toxic, reactive, or odoriferous materials shall be conducted in a chemical fume hood or other appropriate containment enclosure. Whenever hazardous gases or fumes are likely to evolve, an appropriate trap, condenser, or scrubber shall be used to minimize release of material to the environment.
Metallic mercury is highly toxic by skin absorption, inhalation, and ingestion. Lab workers 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 labs is to replace all mercury thermometers with non mercury instruments. Alternatives to mercury thermometers are spirit-filled or digital units.
Fire extinguishers are provided by the University where required by building and life safety code.
Germicidal lamps using ultraviolet light are common fixtures in biological safety cabinets, where they serve to destroy bacteria and molds. These lamps are considered a high-level source of UV radiation; exposure to the lamps without adequate personal protection could result in skin or eye injury.
Acute skin effects due to direct UV exposure vary with dose. Dermal effects include three types: erythema (sunburn), increase in pigmentation (suntanning), and hyperplasia (increase in epidermal cell growth, resulting in enlargement of tissue). UV radiation may also increase the cutaneous effects of certain solvents and photosensitizing chemicals.
Appropriate protection against UV exposure includes long sleeves and laboratory gloves. For individuals particularly sensitive to UV light, suntan lotion on the exposed skin of the face is recommended. ANSI-approved shaded eye protection with side enclosures shall be worn in the vicinity of a UV light fixture not shielded by a physical barrier.
Training is required under the OSHA Hazard Communication Standard, the OSHA Laboratory Standard, the OSHA Bloodborne Pathogens Standard, and various general industry standards such as the OSHA Respiratory Protection Standard. University policy prohibits persons without appropriate training from working in laboratories and other areas where hazardous chemicals are used. Federal law mandates training at the time of initial assignment to a laboratory or work area where hazardous chemicals are present or exposure to bloodborne pathogens is possible. Additional training is required on introduction of a new chemical or biological exposure hazard or new or modified tasks and procedures which affect occupational exposure. Refresher training shall be conducted annually for persons working in areas of potential exposure to chemical hazards and bloodborne pathogens.