ACGIH
The American Conference of Governmental Hygienists is a voluntary membership organization of professional industrial hygiene personnel in governmental or educational facilities. The ACGIH develops and publishes recommended occupational exposure limits each year called Threshold Limit Values (TLV's) for hundreds of chemicals, physical agents, and includes Biological Exposure Indices (BEI).
Action Value
A concentration designated in 29 CFR part 1910 for a specific substance, calculated as an eight-hour time-weighted average, which initiates certain required activities such as exposure monitoring and medical surveillance. The action level is usually half the PEL.
ANSI
The American National Standards Institute is a voluntary membership organization (run with private funding) that develops national consensus standards for a wide variety of devices and procedures. OSHA regulations may "incorporate by reference" an ANSI standard, giving it the force of law which changes as the standard is updated.
Bonding
A safety practice where the electrical potential between two containers is equalized by interconnecting containers with clamps and wire to prevent sparks from a static discharge that can ignite flammable materials being transferred between containers.
(C) or Ceiling
A description usually seen in connection with a published exposure limit. It refers to the concentration that should not be exceeded, even for an instant. It may be written as TLV-C or Threshold Limit Value--Ceiling. (See also THRESHOLD LIMIT VALUE)
Chemical Hygiene Officer (CHO)
An employee who is designated by the employer and who is qualified by training and experience to provide technical guidance in the development and implementation of the provisions of the Chemical Hygiene Plan. This definition is not intended to place limitations on the position description or job classification that the designated individual shall hold within the employer's organizational structure.
Chemical Hygiene Plan (CHP)
A written program developed and implemented by the employer which sets forth procedures, equipment, personal protective equipment and work practices that are capable of protecting employees from the health hazards presented by the hazardous chemicals used in that particular workplace.
Code of Federal Regulations (CFR)
A collection of the regulations established by law. Title 29 of the CFR, Part 1910.1450 (cited as 29 CFR 1910.1450) is the rule governing "Occupational Exposures to Chemical Substances in Laboratories", better known as the "Laboratory Standard".
Designated Area
An area which may be used for work with "select carcinogens", reproductive toxins or substances which have a high degree of acute toxicity. This area may be the entire laboratory or an area under a device such as a laboratory hood.
DOT
The United States Department of Transportation is the Federal agency that regulates the labeling and transportation of hazardous material.
Employee
An individual employed in a laboratory workplace who may be exposed to hazardous chemicals in the course of his or her assignments.
EPA
The Environmental Protection Agency is the governmental agency responsible for the administration of laws to control and/or reduce pollution of air, water, and land systems.
Flash Point
The minimum temperature at which a liquid gives off a vapor in sufficient concentration to form an ignitable mixture with air.
Hazard Communication Standard
29 CFR 1910.1200: Regulation applying to the use of hazardous materials in the workplace, other than laboratories. Cited in the Laboratory Standard as a source of record for definitions of hazardous materials.
Hepatotoxins
Chemicals that are capable of causing liver damage.
High-Efficiency Particulate Air (HEPA) Filter
Highly effective for the removal of sub-micron size particles. National Sanitation Foundation Standard performance test requires that penetration of dioctylphthalate particles of 0.3 micrometers diameter shall not exceed 0.01 percent.
International Agency for Reasearch on Cancer
A division of the World Health Organization, Geneva, Switzerland. One of three sources that OSHA refers to for data or a material's carcinogenicity.
Lethal Concentration 50 (LC50)
The concentration of an air contaminant (LC50) that will kill 50 percent of the test animals in a group during a single exposure.
Lethal Dose 50 (LD50)
The dose of a substance or chemical (LD50) that will kill 50 percent of the test animals in a group within the first 30 days following exposure.
Lower Explosive Limit (LEL)
Also known as the Lower Flammable Limit (LFL). The lowest concentration of a gas that will produce a fire or flash when an ignition source (flame, spark, etc.) is present. It is expressed in percent of vapor or gas in the air by volume. Below the LEL or LFL, the air/contaminated mixture is theoretically too "lean" to burn (see also UEL).
Safety Data Sheet (SDS)
As part of OSHA's Hazard Communication Standard (20 CFR 1910.1200) better known as worker right-to-know law, manufacturers and distributors are required to provide these data sheets which communicate to the end use the hazards a material presents.
Nephrotoxins
A chemical that is capable of causing kidney damage.
Neurotoxins
A chemical that is capable of causing damage to the nervous system.
NFPA
The National Fire Prevention Agency is a voluntary membership organization whose aims are to promote and improve fire protection and prevention. NFPA has published 16 volumes to codes known as the National Fire Codes. Within these codes is Standard No. 704, "Identification of the Fire Hazards of Materials". This is a system that rates the hazard of a material during a fire. these hazards are divided into health, flammability, and reactivity hazards and appear in a well-known diamond system using from zero through four to indicate severity of the hazard. Zero indicates no special hazard and four indicates severe hazard. Many NFPA standards are incorporated into law by reference.
NIOSH
The National Institute for Occupational Safety and Health is a Federal agency that among its various responsibilities trains occupational health and safety professionals, conducts research on health and safety concerns, and tests and certifies respirators for workplace use.
National Toxicology Program (NTP)
A federal program overseen by the Department of Health and Human Services with resources from the National Institute of Health, the Food and Drug Administration, and the Center for Disease Control. One of three sources that OSHA refers to for data on a material's carcinogenicity.
Occupational Safety and Health Administration (OSHA)
A Federal agency under the Department of Labor that publishes and enforeces safety and health regulations for most businesses and industries in the United States.
Permissible Exposure Limit (PEL)
An exposure limit that is published and enforced by OSHA as a legal standard. PEL may either be a time-weighed-average (TWA) exposure limit (8 hours), a 15-minute short-term exposure limit (STEL), or a ceiling (C). The PEL's are found in Tables Z-1, Z-2, or Z-3 of OSHA regulations 1910.1000. (See also TLV).
Personal Protective Equipment (PPE)
Any devices or clothing worn by the worker to protect against hazards in the envirnment. Examples are gloves, respirators, and chemical splash goggles.
Recommended Exposure Limit
The highest allowable airborne concentration that is not expecteed to injure a worker, as determined by NIOSH. It may be expressed as a ceiling limit or as a time-weighted average, usually for 10-hour shifts.
Reproductive Toxins
Chemicals that affect reproductive capabilities including chromosomal damage (mutations) and effects on fetuses.
Short-Term Exposure Limit
Represented as STEL or TLV-STEL, this is the maximum concentration to which workers can be exposed for a short period of time (15 minutes) for only four times thoguhout the day with at least one hour between exposures. Also, the dail TLV-TWA must not be exceeded.
Skin
The designation sometimes appears alongisde a TLV or PEL. It refers to the possibility of absorption of the particular chemical through the skin and eyes. Thus, protection of large surface areas of skin should be considered to prevent skin absorption so that the TLV is not invalidated.
Teratogen
An agent or substance that may cause physical defects in the developing embryo or fetus when a pregnant female is exposed to that substance.
Threshold Limit Value
Airborne concentrations of substances devised by the ACGIH that represents condititions under which it is believed that nearly all workers may be exposed day after day with no adverse effects. TLV's are advisory exposure guidelines, not legal standards, that are based on evidnce from industrial experience, animal studies, or human studies when they exist. There are three different types of TLV's: Time-Weighted Averages (TLV-TWA), Short-Term Exposure Limit (TLV-STEL) and ceiling (TLV-C). (See also PEL).
Time-Weighted Average (TWA)
The average time, over a given work period (e.g. 8 hour workday) of a person's exposure to a chemical or an agent. The average is determined by sampling for the contaminant throughout the time period. Represented as TLV-TWA.
Upper Exposure Limit
Also known as Upper Flammable Limit, is the highest concentration (expressed in percent of vapor or gas in the air by volume) of a substance that wil lburn or explode when an ignition source is present. Theoretically, above this limit the mixture is said to be too "rich" to support combustion. The difference between the LEL and the UEL constitutes the flammable range or explosive range of a substance. that is, if the LEL is 1ppm and the UEL is 5ppm, then the explosive range of the chemical is 1ppm to 5ppm. (See also LEL)