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Terms Used in These Guidelines

Administrative controls: changes in work procedures such as written safety policies, work practices, rules, supervision, schedules, and training with the goal of reducing the duration, frequency, and severity of exposures to hazardous materials or situations (1).

Aerosolization: the generation of liquid droplets or particles, 5 microns in diameter or less, that can be inhaled and retained in the lungs.

ALARA (as low as reasonably achievable): the terminology used most often in relation to radiation exposure levels, designating a work principle or philosophy intended to protect the worker from unnecessary exposure to workplace hazards. This practice involves using or modifying a procedure or workplace element to reduce or eliminate the degree of exposure when reasonable and economically feasible to do so.

Barriers: any method used to separate workers, the outside community, and the environment from any hazardous material utilized; can include primary or secondary barriers.

Biohazardous materials: infectious agents or hazardous biologic materials that present a risk or potential risk to the health of humans, animals, or the environment. The risk can be direct through infection or indirect through damage to the environment. Biohazardous materials include certain types of recombinant DNA, organisms and viruses infectious to humans, animals, or plants (e.g., parasites, viruses, bacteria, fungi, prions, and rickettsia), and biologically active agents (e.g., toxins, allergens, and venoms) that can cause disease in other living organisms or cause significant impact to the environment or community.

Biologic agents: Any microorganism (including, but not limited to, bacteria, viruses, fungi, rickettsiae, or protozoa), infectious substance or any naturally occurring, bioengineered, or synthesized component of any such microorganism or infectious substance capable of causing death, disease, or other biologic malfunction in a human, an animal, a plant, or another living organism; deterioration of food, water, equipment, supplies, or material of any kind; or deleterious alteration of the environment (2).

Biologic materials: Any biologically derived materials or materials that contain biologic species, including bacteria, viruses, microorganisms, genetically modified organisms or microorganisms, or prions, including but not limited to cellular lines, DNA materials, tissues, organs, body fluids, biologic agents and toxins, allergens and cultured cells. Biologic materials are not necessarily pathogenic or hazardous.

Biologic waste: any biohazardous or nonbiohazardous waste containing biologic material, including but not limited to blood and blood products, clinical specimens, pathological waste, animal carcasses and soiled bedding, cultures and stocks of microbial materials, sharps and other items that have been in contact with biohazardous materials, biotechnology byproduct effluents designated for disposal, and laboratory supplies, plastics, or glassware that have been in contact with biologic materials.

Biosafety manual: a laboratory manual developed and implemented by the employer that outlines procedures, equipment, personal protective equipment, and work practices that are capable of protecting employees from the health hazards presented by hazardous biologic materials used in that particular workplace.

Biosafety records: records that are retained as required by regulatory and institutional policies for documentation of employee training, medical surveillance, equipment maintenance and certification, accidents and exposure, inspections and audits, and inventories for chemical and other hazardous agents.

Biosecurity: the system to prevent unauthorized entry to laboratory areas, access to dangerous pathogens, or the unwarranted or accidental release of materials to the outside environment.

Biosecurity manual: laboratory manual that provides practical guidance related to the overall security of personnel reliability and the containment of biologic agents and toxins in the laboratory setting.

Biosurety: An integrated approach to the management of potentially hazardous materials and activities. This includes health, safety, security, environmental protection, emergency management, and community relations concerning activities involving potentially etiologic biological materials and select agents, recombinant DNA, genetic research, and environmental bioremediation (3).

Chemical hygiene plan: a written program developed and implemented by the employer that outlines procedures, equipment, personal protective equipment, and work practices that are capable of protecting employees from the health hazards presented by hazardous chemicals used in that particular workplace and that complies with Occupational Safety and Health Administration (OSHA) regulations (4).

Chemical materials: substances with a distinct molecular composition that are produced by or used in chemical processes. Chemicals can be present in the laboratory as solids, liquids, mists, vapors, or gases.

Compressed gas: any gas or mixture of gases exerting in a container, at a pressure exceeding 40.6 psia at 20º C. Also refers to liquefied and dissolved gases meeting the criteria (5).

Containment: methods used to shield or protect personnel, the immediate work environment, and the community from exposure to hazardous, radiologic, chemical, or biologic materials.

Decontamination: The removing of chemical, biologic, or radiologic contamination from, or the neutralizing of it on, a person, object, or area (6).

Disinfection: the process of reducing or eliminating microorganisms from a surface or space.

Emergency equipment: items used in communication and response to an emergency or incident event. Examples include fire extinguishers, telephones, eye washes, spill clean-up supplies, or fire alarms.

Engineering controls: refers to methods to remove a hazard or place a protective barrier between the worker and the workplace hazard, which usually involves building design elements and specialized equipment.

Ergonomic: Interactions between humans and their total working environment plus stresses related to such environmental elements as atmosphere, heat, light, and sound as well as all tools and equipment of the workplace. The scientific study of or design of equipment and work tasks and their relation to or fit with the operator (1).

Exposure control plan: a written program developed and implemented by the employer that outlines procedures, engineering controls, personal protective equipment, work practices, and other methods that are capable of protecting employees from exposure to bloodborne pathogens and that complies with OSHA requirements (7).

Exposure prevention and hazard mitigation: a process that involves evaluating the incident response procedures to ensure that actions taken during the response do not result in hazardous exposures.

Guidelines and regulatory compliance: safety information and required practices from federal (e.g., U.S. Department of Health and Human Services, Environmental Protection Agency, and OSHA), state, and local regulatory sources, and guidelines (nonregulatory) from agencies, councils, associations, institutes, societies, and acts (e.g., Association of Assessment and Accreditation of Laboratory Animal Care, National Fire Protection Association, or Clinical Laboratory Improvement Amendments).

Hazard communication: a written program that identifies the process for ensuring that information concerning hazards is transmitted appropriately to personnel, to include, but not be limited to, use of signage, symbols, container labels, material safety data sheets, and other written sources describing hazards of a material or space.

Hazard control: methods used to eliminate or reduce the potential for exposures to a hazard.

Incident: an unexpected event that causes or has the potential to cause loss, injury, illness, unsafe conditions, or disruptions to normal procedures.

Incident response plan: a written program that identifies how personnel should react to incidents and other emergencies at their facility.

Institutional safety committees: committees comprising a cross-section of staff with the goal of establishing or monitoring work practices to ensure worker safety, compliance, and awareness with regard to a specific or general workplace hazard. Examples include such local committees as the safety committee, radiation safety committee, institutional animal care and use committee, institutional biosafety committee, chemical safety committee, institution review board, and environmental programs advisory board.

Inventory records: records that track the quantity, form, location, and disposition of any biologic, chemical, or radiologic material in use, stored, or disposed of in a laboratory.

Isotope: one of two or more atomic species of an element differing in atomic weight, but having the same atomic number. Each contains the same number of protons but a different number of neutrons (e.g., uranium 238 and uranium 235).

Laboratory animal allergy (LAA): condition that might develop when susceptible persons are exposed to allergens produced by laboratory animals. LAA is most associated with exposure to fur, saliva, and urine of rats, mice, guinea pigs, and rabbits.

Laboratory emergencies: serious situations or occurrences in the laboratory that happen unexpectedly and demand immediate action.

Laboratory waste management practices: written procedures that describe sterilization, decontamination, and disinfection practices and how the different waste streams (e.g., biologic, chemical, or radiologic) generated in the laboratory will be handled to comply with regulatory and institutional requirements.

Material safety data sheet (MSDS): a fact sheet summarizing information regarding material identification for a chemical product or mixture, including hazardous ingredients; health, physical, and fire hazards; first aid; chemical reactivities and incompatibilities; spill, leak, and disposal procedures; and protective measures required for safe handling and storage.

Medical surveillance program: the ongoing, systematic collection of health data that signal either biomarkers of exposure or early signs of adverse health outcomes from known biologic materials and toxicants in persons working with those materials. Includes a program for preemployment screening, ongoing monitoring, and postexposure management.

Mitigate: to correct identified deficiencies and to make a hazard less severe. This includes corrective actions taken as a result of an inspection or audit, or after an incident.

Nonionizing radiation: electromagnetic radiation that does not cause ionization (i.e., does not remove an electron completely from an atom or molecule). Examples include ultraviolet, laser, infrared, microwave, and radio waves.

Nonroutine samples/specimens: samples or specimens received that normally are not handled by the facility and might include materials that potentially pose a greater or different hazard than encountered normally.

Personal protective equipment (PPE): items worn by laboratory workers to prevent direct exposure to hazardous materials, including gloves, gowns, aprons, coats, containment suits, shoe covers, eye and face shields, respirators, and masks.

Personnel training program: the required training and follow-up evaluation to ensure that staff are capable of performing their duties in accordance with the institution's safety program. A comprehensive training program should include such areas as biosafety, biosecurity, hazardous waste management, emergency response, sample and specimen receipt and accessioning, specimen packaging and shipping, testing procedures, and hazard communication.

Physical environment: location where work is performed. Also includes the associated equipment, materials, air, and other objects.

Physical hazards: unsafe conditions in the workplace that can cause injury or illness. Examples include, but are not limited to, ergonomic concerns, exposure to hot and cold, electricity, compressed gas cylinders, noises, and sharps.

Prions: a transmissible agent that can cause neurodegenerative disease in humans and animals. Having no genetic material, a prion is a protein that normally is harmless. In a process that is not fully understood, the prion folds into an abnormal shape that also can cause other normal prions to fold into abnormal shapes.

Primary barriers: specialized laboratory equipment with engineering controls designed to protect against exposure to hazardous laboratory materials, including, but not limited to, biologic safety cabinets, chemical fume hoods, enclosed containers, bench shields, animal cages, and engineered sharps injury-protection devices (e.g., safety needles, safety scalpels, and sharps containers).

Radiation safety manual: a laboratory manual that details how the laboratory handles, stores, and disposes of radioactive material in a safe manner according to its user license with the Nuclear Regulatory Commission.

Radiologic materials: radioisotopes, radioactive waste products, and chemical or biologic materials that have been modified to include radioisotope labels.

Radiologic monitoring devices: devices that provide a scientific determination of amount, rate, and distribution of radiation emitted from a source of ionizing radiation. An example is a Geiger counter.

Records management system: a paper or electronic system for tracking the creation, receipt, revision, and retention of laboratory records in accordance with applicable regulatory standards and guidelines and in accordance with any applicable quality assurance or quality control standard for the laboratory. Records can include, but are not limited to, audio and video recordings, photographs or other graphic images, and e-mail messages.

Research animals: animals used in the laboratory. When evaluating hazards of research animals, laboratorians should consider the risks inherent to the species itself, those associated with handling the animals (e.g., bites, scratches, and allergens), and the risks for handling the bedding and other associated waste products.

Respiratory protection program: a detailed plan describing the use of PPE to protect laboratory workers from respiratory exposure to hazardous materials. Includes the required respiratory protection devices to be used for various procedures and describes the required fit-testing procedure necessary before use of respirators. Must comply with OSHA regulations (8).

Risk assessment: a process to evaluate the probability and consequences of exposure to a given hazard, with the intent to reduce the risk by establishing the appropriate hazard controls to be used.

Routes of exposure: paths by which humans or other living organisms come into contact with a hazardous substance. Three routes of exposure are breathing (inhalation), eating or drinking (ingestion), and contact with skin (dermal absorption).

Safety manuals: collections of policies, procedures, and work practices intended for guidance in protection against identified and potential workplace hazards.

Safety program management: institutional general safety, biosafety, biosecurity, chemical, radiologic, and emergency-response programs and plans that all staff are required to follow to manage possible workplace hazards.

Sample: a material of nonbiologic origin (e.g., water or soil) submitted for analysis to an environmental or research laboratory. Samples might have the potential to contain biologic materials.

Secondary barriers: facility design and construction features to include, but not be limited to, directional air flow, entrance airlocks, controlled-access zones, HEPA-filtered exhaust air, facility controls, decontamination equipment, eyewash stations, protective showers, and sinks for hand washing.

Sharps: items capable of cutting or piercing human skin. Examples include hypodermic needles, syringes (with or without attached needles), Pasteur pipettes, scalpel blades, suture needles, blood vials, needles with attached tubing, and culture dishes (regardless of presence of infectious agents). Also included are other types of broken or unbroken glassware that have been in contact with infectious agents (e.g., used microscope slides and cover slips).

Specimen: biologic material such as blood or tissue submitted for analysis to a clinical, public health, or research laboratory.

Standard operating procedures: established procedures to be followed in carrying out a given operation or in a given situation. Development of procedures is based on prudent laboratory practices that conform to safety guidelines and regulatory requirements.

Standard operating procedures for emergency response: procedures developed to guide the response of personnel to specific emergency situations. These can include the facility emergency response plan, the chemical/biological spill response procedure, the continuity of operations plan, or the occupant emergency plan.

Sterilization: the use of physical or chemical methods to completely destroy or eliminate all forms of microbial life.

Universal precautions: guidelines recommended by CDC for reducing the risk for transmission of bloodborne and other pathogens in hospitals, laboratories, and other institutions in which workers are potentially exposed to human blood and body fluids. The precautions are designed to reduce the risk for transmission of microorganisms from both recognized and unrecognized sources of infection in hospitals, laboratories, and other institutions to the workers in these facilities (9).


  1. Plog BA, Quinlan PJ, eds. Fundamentals of industrial hygiene. 5th ed. Itasca, IL: NSC Press; 2002.
  2. Select Agents and Toxins, 42 C.F.R. Sect. 73.1 (2008).
  3. US Department of Energy. Biosurety Executive Team charter. Washington, DC: US Department of Energy; 2006. Available at Accessed March 22, 2011.
  4. Occupational Exposure to Hazardous Chemicals in Laboratories, 29 C.F.R. Sect. 1910.1450 (2006).
  5. Compressed Gas Association, Inc. Safe handling of compressed gases in containers. 9th ed. Arlington, VA: Compressed Gas Association; 2002.
  6. McGraw-Hill, Parker SP. McGraw-Hill Dictionary of scientific and technical terms. 6th ed. New York, NY: The McGraw-Hill Companies, Inc.; 2002.
  7. Bloodborne Pathogens, 29 C.F.R. Sect. 1910.1030 (2008).
  8. Personal Protective Equipment. Respiratory Protection, 29 C.F.R. Sect. 1910.134 (2008).
  9. CDC. Update: universal precautions for prevention of transmission of human immunodeficiency virus, hepatitis B virus and other bloodborne pathogens in health-care settings. MMWR 1988;37:377--82, 387--8.

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