The Sonic Gates

Glossary of EHS Related Terms

Tell a friend about this page.
All fields required.
Can be sent to only one email address at a time.
Share Facebook Icon Twitter Icon

Office of Environmental Health and Safety


Glossary of EH&S Related Terms




Absolute

A chemical substance that is relatively free of impurities.

Absorb

The penetration of a solid substance by a liquid as by capillary, osmotic, solvent or chemical action.  Chemicals are readily absorbed into the human blood stream through the eyes or cuts in the skin.

ACGIH

American Conference of Governmental Industrial Hygienist.  Professional organization responsible for creation of the TLV consensus exposure guidelines.

Acid

An organic or inorganic compound with a pH of less than 7.  Acidic materials are corrosive to human tissue.

Action Level

A concentration designated in 29 CFR part 1910 for a specific substance, calculated as an eight (8)-hour time-weighted average, which initiates certain required activities such as exposure monitoring and medical surveillance.

Acute Toxicity

Refers to adverse effects suffered as the result of a short, one-time exposure to toxic materials.  It occurs within a relatively short period.  Exposure is measured in seconds, minutes, or hours relative to inhalation or skin absorption.

Adsorb

Collection of gas or liquid molecules on the surface of another material.  For sampling of most organic vapors, activated charcoal is a good absorbent.

Base

Chemical compounds that have a pH of greater then 7.  Bases are also referred to as alkalis or caustic materials and can be corrosive to human tissue.

Boiling Point

The temperature at which the vapor pressure of a liquid is equivalent to the surrounding atmospheric pressure and the liquid rapidly becomes a vapor.  Flammable substances possessing low boiling points are considered fire hazards.

BTU

British Thermal Unit. A measure of heat equal to 1/800th of the heat required to raise the temperature of a pound of water from 32oF to 212oF at one atmosphere pressure.

Carcinogen

A chemical is considered to be a carcinogen if:

·       it has been evaluated by the International Agency for Research on Cancer [IARC] and found to be a carcinogen or potential carcinogen;

·       It is listed as a carcinogen or potential carcinogen in the Annual Report on Carcinogens published by the National Toxicology Program (NTP) (latest edition); or

·       It is regulated by OSHA as a carcinogen.

Caustic

Any strongly alkaline material that produces either corrosion or irritation to living tissue.

Chemical Hygiene Plan

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 hazardous chemicals used in that particular workplace.  Follow the link to the ECU Chemical Hygiene Plan

Chemical Reactivity

The ability of a material to chemically change, possibly resulting in explosion hazards or the liberation of toxic fumes.

Chronic Toxicity

Adverse health effects resulting from repeated or long-term exposure to toxic materials.

Combustible Liquid

Any liquid having a flashpoint at or above 100°F (37.8°C) but below 200°F(93.3°C), except any mixture having components with flashpoints of 200°F (93.3°C), or higher, the total volume of which make up 99 percent or more of the total volume of the mixture by OSHA and NFPA definition.

Compressed Gas

·       A gas, or mixture of gases having in a container, an absolute pressure exceeding 40 psi at 70°F (21.1°C); or

·       A gas, or mixture of gases having in a container, an absolute pressure exceeding 104 psi at 130°F (54.4°C) regardless of the pressure at 70°F (21.1°C); or

·       A liquid having a vapor pressure exceeding 40 psi at 100°F (37.8°C) as determined by ASTM D-323-72.

Corrosive

A chemical that causes visible destruction of, or irreversible alterations in, living tissue by chemical action at the site of contact.

Cryogenic Liquid

Severely cold (-60°C to -270°C) and pressurized liquids.  They present an explosion hazard due to high pressures and can cause thermal damage to living tissue.

Designated Area

An area that must be assigned by the Principle Investigator or Lab Supervisor for the use of "select carcinogens" reproductive toxins, or substances which have a high degree of acute toxicity. A designated area may be the entire laboratory, an area of a laboratory or a device such as a laboratory fume hood.

Embryotoxin

A substance shown to adversely affect a developing embryo at a particular concentration but does not affect the pregnant female.

EPA

The Environmental Protection Agency federally regulates and enforces Federal environmental protection standards.

Explosive

A chemical that causes a sudden, almost instantaneous release of pressure, gas, and heat when subjected to sudden shock, pressure, or high temperature.

Flammable Gas

A gas that forms a flammable mixture with air at a concentration of 13 percent by volume or less, or forms a range of flammable mixtures with air that are wider than 12% by volume, regardless of lower flammable limit.

Flammable Liquid

Any liquid having a flashpoint below 100°F (37.8°C) except any mixture having components with flashpoints of 100°F (37.8°C) or higher, the total of which make up 99 percent or more of the total volume of the mixture.

Flammable Solid

A solid that is liable to cause a fire through friction, absorption of moisture, spontaneous chemical change, or retained heat from manufacturing or processing, or which can be ignited readily and when ignited burns so vigorously and persistently as to create a serious hazard.

Flammability

The ease with which a liquid, solid, or gas will ignite, either spontaneously (pyrophoric) or as the result of a spark or an open flame.  The more flammable a material, the more readily ignition occurs.

Flashpoint

The minimum temperature at which a liquid gives off a vapor in sufficient concentration to ignite.

Fume Hood

A device located in a laboratory, enclosed on five sides with a movable sash or fixed partial sash enclosed on the remaining side; constructed and maintained to draw air from the laboratory and to prevent or minimize the escape of air contaminants into the laboratory; and allows chemical manipulations to be conducted in the enclosure without insertion of any part of the employee's body other than hands and arms.

Hazardous Chemical

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 in exposed employees. The term "health hazard" includes chemicals which are carcinogens, toxic or highly toxic agents, reproductive toxins, irritants, corrosives, sensitizers, hepatotoxins, nephrotoxins, neurotoxins, agents which act on the hematopoietic systems, and agents which damage the lungs, skin, eyes, or mucous membranes.

Hood

A device/location in a laboratory, enclosed on five sides, to draw air from the laboratory and to prevent or minimize the escape of the air contaminants into the laboratory.  Chemical manipulations may be conducted in the enclosure without inserting any portion of the employees body other than hands and arms.

IDLH

Immediately Dangerous to Life and Health.  Maximum Concentration from which one could escape within 30 minutes without any escape-impairing symptoms or any irreversible health effects.

Infectious Waste

Waste that is capable of producing disease.  For waste to be considered infectious, it must contain oncogenic viruses or other pathogenic microorganisms with sufficient virulence and quantity that exposure to the waste could result in an infectious disease.

Irritant

Chemical substances that cause tissue inflammation or soreness upon absorption, inhalation, or ingestion.

LD50

The quantity of material that when ingested, injected, or applied to the skin as a single dose, will cause death of 50% of the test animals. The test conditions should be specified, the value is expressed in g/kg or mg/kg of body weight.

LEL

Lower Explosive Limit - The lower limit of flammability of a gas or vapor at ordinary ambient temperatures expressed in percent of the gas or vapor air by volume.  This limit is assumed constant for temperatures up to 250°F(120°C) and is normally listed on a product's material safety data sheet.

LFL

Lower Flammable Limit - The lower limit of flammability of a gas or vapor at ordinary ambient temperatures expressed in percent of the gas or vapor air by volume.  This limit is assumed constant for temperatures up to 250°F(120°C) and is normally listed on a product's material safety data sheet.

MSDS

Material Safety Data Sheets are produced by chemical manufacturers, distributors and importers.  They relay chemical, physical, and health hazard information about specific chemicals or mixtures.  See How to Read a MSDS.

Mutagen

Chemical compounds that induce mutations in DNA and living cells.

NIOSH

National Institute of Occupational Safety and Health.  Part of the Centers for Disease Control of the Public Health Service of the Department of Health and Human Services.  It conducts research and development in occupational safety and health, advises OSHA in rulemaking, approves respirators and promotes health and safety training and education.

Neutralize

To alter acidic or basic compounds to a pH of 7, making it chemically neutral.

Organic

Any chemical compound containing carbon.

OSHA

Occupational Safety and Health Administration - the branch of federal government charged with worker health and safety.

Oxidizer

A chemical that initiates or promotes combustion in materials, thereby causing fire either of itself or by the release of oxygen or other gases.

Oxidizing Agent

Oxygen-containing material which can decompose, generating oxygen.

PEL

Permissible Exposure Limits for the work place, set by regulation and enforced by OSHA.  Most of these limit values were originally set, by consensus, by the ACGIH to assist industrial hygienists in implementing exposure control programs.  As law, these are listed in 29 CFR 1910.1000 and subject to revision through the regulatory process.

Poison

Any substance harmful to living tissue when applied in small doses.  Determining factors include concentration, exposure time, particle size, affinity for tissue, and sensitivity of the exposed tissue to that compound.

Pyrophoric

Any solid or liquid that has the property of spontaneous ignition in air.

Radioactivity

Nuclear transformation, either by natural or artificial means, resulting in emission of energy in the form of alpha, beta, or gamma rays.  Amounts of radioactive material are described by the rate of radioactive decay, the Curie (Ci), or in metric multiples and fractions thereof.

REL

Recommended Exposure Level.  Exposure guidelines published by NIOSH.

Reactivity

The proclivity of a compound to chemically react with other substances or itself, resulting in the liberation of energy.  Can cause the formation of toxic or corrosive materials, pressure buildup, and temperature fluctuations.

Reproductive Toxins

Chemicals that affect reproductive capabilities: chromosomal damage (mutations) and effects on fetuses (teratogenesis).

S or Skin

A notation on some of the TLVs and OSHA standards indicating that the substance may be absorbed by the skin, mucous membranes and eyes, either by air or direct contact.  This exposure must be considered as part of the total exposure to avoid overexposure.

Sensitizer

A chemical that causes a substantial proportion of exposed people or animals to develop an allergic reaction in normal tissue after repeated exposure to the chemical.

Teratogen

Chemical and physical agents which interfere with normal embryonic development.  Teratogens may produce congenital malformations or death of the fetus without inducing damage to the pregnant female.

TLV

Threshold Limit Value. American Conference of Governmental Industrial Hygienists recommended exposure limits.  Consensus standards.

TWA

Time Weighted Average is the concentration for a normal 8-hour working day (40 hours/week) to which workers may be exposed without anticipated adverse effect. 

Ultraviolet Light

Radiation in the electromagnetic spectrum with wavelengths of 100 - 3900 Ångstroms

Volatility

The tendency of a liquid or solid to pass into the vapor state at a particular temperature.

Water Reactive

A chemical that reacts with water to release a gas that is either flammable or presents a health hazard.



ECU Environmental Health & Safety
210 East Fourth Street | Greenville, NC 27858-4353 USA
252.328.6166 | Contact Us
© 2014 | Terms of Use | Last Updated: 2014-04-09
Give To East Carolina University