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Appendix VII

Glossary

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.

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 absorber.

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.

Carcinogen

A chemical is considered to be a carcinogen if:

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

2. 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

3. 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.

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 100F (37.8C) but below 200F (93.3C), except any mixture having components with flashpoints of 200F (93.3C), 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

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

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

3. A liquid having a vapor pressure exceeding 40 psi at 100F(37.8C) 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 (-60C to -270C) 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 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 environmental protection.

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 100F (37.8C) except any mixture having components with flashpoints of 100F (37.8C) 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, enclosure on five sides with a movable sash or fixed partial 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.

Highly Toxic

A chemical falling within any of the following categories:

1. A chemical that has a median lethal dose (LD₅₀) of 50 milligrams or less per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each.
2. A chemical that has a median lethal dose (LD₅₀) of 200 milligrams or less per kilogram of body weight when administered by continuous contact for 24 hours (or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between two and three kilograms each.

3. A chemical that has a median lethal concentration (LC₅₀) in air of 200 parts per million by volume or less of gas or vapor, or 2 milligrams per liter or less of mist, fume, or dust, when administered by continuous inhalation for one hour (or less if death occurs within one hour) to albino rats weighing between 200 and 300 grams each.

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.

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 - same definition as LFL.

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 250F(120C) and is normally listed on a product's material safety data sheet.

LS

Laboratory Supervisor

MOSH

Maryland Occupational Safety and Health Administration - the state agency charged with worker health and safety. MOSH promulgates Maryland occupational safety and health standards.

MSDS

Material Safety Data Sheets are produced by chemical manufacturers and importers. They relay chemical, physical, and hazard information about specific chemicals.

Mutagen

Chemical compounds that induce mutations in DNA and living cells.

Neutralize

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

Organic Materials

Any chemical compound containing carbon.

OSHA

Occupational Safety and Health Administration - the branch of federal government charged with worker health and safety. Maryland has a state operated program that is at least as effective as the federal program maintaining jurisdiction over UM known by the acronym MOSH.

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.

PI

Principal Investigator

Poison

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

Pyrophoric Material

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.

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 which affect the reproductive capabilities including chromosomal damage (mutations) and effects on fetuses (teratogenesis).

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.

STEL

Short Term Exposure Limit, a 15-minute time-weighted average exposure which should not be exceeded at any time during a work day, even if the eight-hour time-weighted average is within the TLV.

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 indicates the concentration of a chemical substance in the atmosphere that is considered non-hazardous in a person's normal working life.

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.

Toxic

A chemical falling within any of the following categories:

1. A chemical that has a median lethal dose (LD₅₀) of more than 50 milligrams per kilogram but not more than 500 milligrams per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each.

2. A chemical that has a median lethal dose (LD₅₀) of more than 200 milligrams per kilogram but not more than 1000 milligrams per kilogram of body weight when administered by continuous contact for 24 hours (or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between two and three kilograms each.

3. A chemical that has a median lethal concentration (LC₅₀) in air of more than 200 parts per million but not more than 2,000 parts per million by volume of gas or vapor, or more than two milligrams per liter but not more than 20 milligrams per liter of mist, fume, or dust, when administered by continuous inhalation for one hour (or less if death occurs within one hour) to albino rats weighing between 200 and 300 grams each.

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.

Appendix VIII

References

American Chemical Society. Safety in Academic Chemistry Laboratories, 5th Edition, 1990.

American National Standards Institute. ANSI Z358.1-1990 American National Standard For Emergency Eyewash and Shower Equipment, New York, N.Y. 1990.

American National Standards Institute. ANSI Z87.1 1989 American National Standard for Occupational and Educational Eye & Face Protection, New York, N.Y., 1989.

Benedetti, Robert P., ed. Flammable and Combustible Liquids Code Handbook, Quincy, MA: National Fire Protection Association, 1990.

Bretherick, L., eds. Hazards in the Chemical Laboratory, London: Royal Society, 1986.

Bretherick, L. Handbook of Reactive Chemical Hazards, London: Butterworths, 1981.

Centers for Disease Control-National Institutes of Health. Biosafety in Microbiological and Biomedical Laboratories, 3rd Edition, U.S. Public Health Service, May, 1993.

Committee on Hazardous Substances in the Laboratory Assembly of Mathematical and Physical Sciences; National Research Council. Prudent Practices for Handling Chemicals. Washington D.C. National Academy Press, 1981.

Department of Environmental Health and Safety, University of Louisville. Laboratory Safety Manual. January 1989.

Freeman, N.T. And J WhiteHead. Introduction to Safety in the Chemical Laboratory. Orlando. Academic Press Inc., 1982.

Office of Environmental Health and Safety, University of Virginia. Laboratory Survival Manual, 3rd ed., 1993.

Right-to-Know Pocket Guide for School and University Employees. Genium Publishing Corporation, Schenectady, NY 1990

Singer, James; Pesticide Safety: Guidelines for Personnel Protection; Davis, October, 1982.

Supervisors Safety Manual. 6th ed. Chicago: National Safety Council, 1985.

U.S. Department of Health, Education, and Welfare et al. Hazards in the Chemistry Laboratory; Student Manual Sept. 1979.

U.S. Department of Health, Education, and Welfare, et al.; NIOSH Health and Safety Guide for Pesticide Formulators; Cincinnati, May, 1977.

U.S. Environmental Protection Agency, Private Pesticide Applicators: Training Manual, February, 1989.

Young Jay A., ed. Improving Safety in the Chemical Laboratory, A Practical Guide 2nd ed., Wiley & Sons, Inc., New York, 1991.

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