Acronyms and Common Terms Used In Material Safety Data Sheets
Version - 65k)
Acid - Any chemical that
undergoes dissociation in water with the formation of hydrogen
ions. Acids turn litmus paper red and have pH values of 0 to 6. They
may cause severe skin burns.
Level Exposure level at which certain OSHA regulations take effect.
Acute Effect - Adverse effect on a human or
animal that has severe symptoms developing rapidly and coming
quickly to a crisis. Also see chronic effect.
Toxicity - Acute effects resulting from a single dose of or
exposure to a substance. Ordinarily used to denote effects in
ACGIH - American
Conference of Governmental Industrial Hygienists is an organization
of professional personnel in governmental agencies or
educational institutions who are employed in occupational safety
and health programs.
Adenocarcinoma - A
tumor with glandular (secreting) elements.
- Any disease of a gland.
Adhesion - A union
of two surfaces that are normally separate.
- A fine aerial suspension of particles sufficiently small in size
to confer some degree of
stability from sedimentation (for
example: smoke or fog).
Air Line Respirator
- A respirator that is connected to a compressed breathing air
source by a hose
of small inside diameter. The air is delivered
continuously or intermittently in a sufficient
volume to meet
the wearer's breathing requirements.
Respirator - A respirator that uses chemical absorbents to
remove specific gases and
vapors from the air or that uses a
mechanical filter to remove particulate matter. An air purifying
respirator must only be used when there is sufficient oxygen to
sustain life and the air
contaminant level is below the
concentration limits of the device.
Alkali - The hydroxides
and carbonates of the alkali metals and alkaline earth metals. They
neutralize acids, impart a soapy feel to aqueous solutions and
are the commonest cause of occupational dermatitis.
Approved Respirator Wearer - Any personnel who have
met the following requirements is considered to
be an approved
(1) medical approval
within the past 12 months;
(2) quantitative fit test must be performed
within 30 days of medical approval; and
(3) annual training in the use and care of
- A vapor or gas that can cause injury or death by reducing the
amount of oxygen
available to breathe.
- A water soluble compound capable of reacting with an acid to form
a salt by releasing an un-shared pair of electrons to the acid
or by receiving a proton from the acid.
- Not recurrent or not tending to progress.
Bioassay - A
determination of the concentration of a substance in a human body by
an analysis of urine, feces, blood, bone, or tissue.
Biodegradable - Capable of being broken down into
individual components by the action of living things.
Biopsy - Removal and examination of tissue from the
Boiling Point - The temperature
at which a liquid changes to a vapor state at a given pressure. The
boiling point usually expressed in degrees Fahrenheit at sea
level pressure (760mm Hg, or one atmosphere). For mixtures, the
initial boiling point or the boiling range may be given. Flammable
materials with low boiling points generally present special fire
hazards. Some approximate boiling points:
-44 degrees F
-28 degrees F
100 degrees F
113 degrees F
387 degrees F
BOM or BuMines - Bureau of
Mines, U.S. Department of Interior.
- The interconnecting of two objects by means of a clamp and bare
wire. Its purpose is to equalize the electrical potential
between the objects to prevent a static discharge when
transferring a flammable liquid from one container to another. The
conductive path is provided by clamps that make contact with the
charged object and a low resistance flexible cable that allows
the charge to equalize. See Grounding.
Bulk Density - Mass of
powdered or granulated solid material per unit of volume.
Centigrade, a unit of temperature.
C or Ceiling - The maximum
allowable human exposure limit for an airborne substance that is not
to be exceeded even momentarily. Also see PEL and TLV.
CAA - Clean Air Act was enacted to
regulate/reduce air pollution. CAA is administered by EPA.
Carcinogen - A substance or agent capable of causing or producing
cancer in mammals, including humans. 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; or
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.
Carcinogenicity - The ability to produce cancer.
A malignant tumor. A form of cancer.
CAS - Chemical Abstracts
Service is an organization under the American Chemical Society.
CAS abstracts and indexes chemical literature from all over the
world in Chemical Abstracts. CAS Numbers are used to identify
specific chemicals or mixtures.
CAS-RN - Chemical Abstract
Standard Registry Number
Caustic - See alkali.
cc - Cubic
centimeter is a volume measurement in the metric system that is
equal in capacity to one milliliter (ml). One quart is about 946
CCA - Clean Air Act
Ceiling Limit - Maximum
amount of a toxic substance allowed in workroom air at any time.
Central Nervous System - The brain and spinal cord. These organs
supervise and coordinate the activity of the entire nervous
system. Sensory impulses are transmitted into the central
nervous system, and motor impulses are transmitted out.
Comprehensive Environmental Response, Compensation, and Liability
Act of 1980. The Act requires that the Coast Guard National Response
Center be notified in the event of a hazardous substance
release. The Act also provides for a fund (the Superfund) to be
used for the cleanup of abandoned hazardous waste disposal sites.
Cervix - The lower end of the uterus extending into the vagina.
CFR - Code of Federal Regulations. A collection of the regulations
that have been promulgated under United States law.
Chemical - Any element, chemical compound or mixture of elements
and/or compounds where chemical(s) are or distributed.
Chemical Cartridge Respirator - A respirator that uses various
chemical substances to purify inhaled air of certain gases and
vapors. This type respirator is effective for concentrations no
more than ten times the TLV of the contaminant, if the
contaminant has warning properties (odor or irritation) below the
Chemical Hygiene Plan - A written program which sets forth
policy and procedures capable of protecting employees from the
health hazards associated with their workplace.
Chemical Name -
The name given to a chemical in the nomenclature system developed
by the International Union of Pure and Applied Chemistry (IUPAC) or
the Chemical Abstracts Service (CAS).
Chemical Family - A
group of single elements or compounds with a common general name.
Example: acetone, methyl ethyl ketone (MEK), and methyl isobutyl
ketone (MIBK) are of the aldehyde family.
Chemical Source -
The arrangement within the molecule of atoms and their chemical
CHEMTREC - Chemical Transportation Emergency Center is a
national center established by the Chemical Manufacturers
Association (CMA) to relay pertinent emergency information
concerning specific chemicals on requests from individuals. CHEMTREC
has a 24-hour toll-free telephone number (800-424-9300) to
help respond to chemical transportation emergencies.
Chronic - A
long-term period of action in weeks, months or years.
Effect - An adverse effect on a human or animal body, with symptoms
which develop slowly over a long period of time or which recur
frequently. Also see acute.
Chronic Exposure - Long-term contact
with a substance.
Chronic Toxicity - Adverse (chronic) effects
resulting from repeated doses of or exposures to a substance over
a relatively prolonged period of time. Ordinarily used to denote
effects in experimental animals.
Clean Air Act - See CAA.
Clean Water Act - Federal law enacted to regulate/reduce water
pollution. CWA is administered by EPA.
CMA - Chemical
Manufacturers Association. See CHEMTREC.
CO - Carbon monoxide is
a colorless, odorless, flammable, and very toxic gas produced by
the incomplete combustion of carbon. It is also a by-product of many
CO2 - Carbon dioxide is a heavy,
colorless gas that is produced by the combustion and
decomposition of organic substances and as a by-product of many
COC- Cleveland Open Cup is a flash point test
Combustible - A term used by NFPA, DOT, and others to
classify certain liquids that will burn, on the basis of flash
points. Both NFPA and DOT generally define combustible liquids as
having a flash point of 100F (37.8C) or higher but below
200F (93.3C). Also see flammable. Non-liquid substances such as wood
and paper are classified as ordinary combustibles by NFPA.
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 ninety-nine (99) percent or more of the
total volume of the mixture.
Common Name - Any
identification, such as code name, code number, trade
name, or generic name, other than its chemical name, used to
identify a chemical.
Compressed Gas -
1. A gas or
mixture of gases having, in a container, an absolute pressure
exceeding 40 psi at 700F; or
2. A gas or mixture of gases
having, in a container, an absolute pressure exceeding 104 psi at
1300F regardless of the pressure at 700F; or
3. A liquid having a
vapor pressure exceeding 40 psi at 100F as determined by ASTM
Conc - See concentration
Concentration - The
relative amount of a substance when combined or mixed with other
substances. Examples: 2 ppm hydrogen sulfide in air, or a 50 percent
Conditions to Avoid - Conditions encountered
during handling or storage that could cause a substance to become
Confined Space - Any area which has limited openings
for entry and exit that would make escape difficult in an
emergency, has a lack of ventilation, contains known and
potential hazards, and is not intended nor designated for continuous
Conjunctivitis - Inflammation of the
conjunctiva, the delicate membrane that lines the eyelids and
covers the eyeballs.
Container - Any bag, barrel, bottle, box,
can, cylinder, drum, reaction vessel, storage tank, or the like
that contains a hazardous chemical. For purposes of material safety
data sheets or HCS, pipes or piping systems are not considered
to be containers.
Corrosive - A chemical that causes visible
destruction of, or irreversible alterations in, living tissue by
chemical action at the site of contact. For example, a chemical is
considered to be corrosive if, when tested on the intact skin of
albino rabbits by the method described by the U.S. Department of
Transportation in Appendix A to 49 CFR Part 173, it destroys or
changes irreversibly the structure of the tissue at the site of
contact following an exposure period of 4 hours. This term shall
not refer to action on inanimate surfaces.
CPSC - Consumer
Products Safety Commission has responsibility for regulating
hazardous materials when they appear in consumer goods. For CPSC
purposes, hazards are defined in the Hazardous Substances Act
and the Poison Prevention Packaging Act of 1970.
Cleansing of a diseased surface.
Cutaneous Toxicity - See
CWA - Clean Water Act was enacted to
regulate/reduce water pollution. It is administered by EPA.
Cyst - A sac containing a liquid. Most cysts are harmless.
Cytology - The scientific study of cells.
DASHO - Designated
Agency Safety and Health Official is the executive official of a
Federal Department or Agency who is responsible for safety and
occupational health matters within a Federal agency, and is so
designated or appointed by the head of the agency.
- Breakdown of a material or substance (by heat, chemical
reaction, electrolysis, decay, or other processes) into parts or
elements or simpler compounds.
Density - The mass (weight) per
unit volume of a substance. For example, lead is much more dense
Depressant - A substance that reduces a bodily
functional activity or an instinctive desire, such as appetite.
Dermal - Relating to the skin.
Dermal Toxicity - Adverse effects
resulting from skin exposure to a substance. Ordinarily used to
denote effects in experimental animals.
Designated Area - An area
that may be used for work involving carcinogens, reproductive
toxins or acutely toxic chemicals. A designated area may be the
entire laboratory, a controlled area within the laboratory or
engineering controls such as a chemical hood.
DHHS - U.S.
Department of Health and Human Services (replaced U.S. Department
of Health, Education and Welfare). NIOSH and the Public Health
Service (PHS) are part of DHHS.
Dike - A barrier constructed to
control or confine hazardous substances and prevent them from
entering sewers, ditches, streams, or other flowing waters.
Ventilation - Air flow designed to dilute contaminants to
acceptable levels. Also see general ventilation or
DOL - U.S. Department of Labor. OSHA and MSHA are part of DOL.
DOT - U.S. Department of Transportation.
Dry Chemical - A
powdered fire extinguishing agent usually composed of sodium
bicarbonate, potassium bicarbonate, etc.
Dysplastic - An abnormality of development.
Ectopic Pregnancy - The fertilized ovum becomes implanted outside of
Edema - An abnormal accumulation of clear watery
fluid in the tissues.
Endocrine Glands - Glands that regulate
body activity by secreting hormone.
Endometrium - The mucous
membrane lining the uterus.
Engineering Controls - Environmental,
mechanical, or structural factors that serve to encourage,
facilitate, or complement safe and healthful behaviors in the
workplace.Engineering controls work by removing the worker from
the hazard or by removing the hazard from the work environment
(by using ventilation in particular).
- Information obtained as a result of conducting environmental
testing designed to study the effects on aquatic and plant life.
EPA - U.S. Environmental Protection Agency.
Science concerned with the study of disease in a general
population. Determination of the incidence (rate of occurrence) and
distribution of a particular disease (as by age, sex, or
occupation) that may provide information about the cause of the
Epithelium - The covering of internal and external
surfaces of the body.
Estrogen - Principal female sex hormone.
Evaporation Rate - The rate at which a material will vaporize
(evaporate) when compared to the known rate of vaporization of a
standard material. The evaporation rate can be useful in evaluating
the health and fire hazards of a material. The designated
standard material is usually normal butyl acetate (NBUAC or
n-BuAc), with a vaporization rate designated as 1.0. Vaporization
rates of other solvents or materials are then classified as:
1. FAST evaporating if greater than 3.0. Examples: Methyl Ethyl
Ketone = 3.8, Acetone=5.6, Hexane = 8.3.
2. MEDIUM evaporating
if 0.8 to 3.0. Examples: 190 proof (95%) Ethyl Alcohol = 1.4, VM
& P Naphtha = 1.4, MIBK = 1.6
3. SLOW evaporating if less than
0.8. Examples: Xylene =0.6, Isobutyl Alcohol = 0.6, Normal Butyl
Alcohol = 0.4, Water = 0.3, Mineral Spirits = 0.1.
Explosive - A chemical that causes a sudden, almost instantaneous
release of pressure, gas, and heat when subjected to sudden
shock, pressure, or high temperature.
of vapors in the air that form explosive mixtures.
Exposed - State of being open and vulnerable to a hazardous chemical
in the course of employment by inhalation, ingestion, skin
contact, absorption, or any other course; includes potential
(accidental or possible) exposure.
Extinguishing Media - The fire
fighting substance to be used to control a material in the event
of a fire. It is usually named by its generic name, such as fog,
foam, water, etc.
Eye Protection - Recommended safety
glasses, chemical splash goggles, face shields, etc. to be
utilized when handling a hazardous material.
F - Fahrenheit is a
scale for measuring temperature. On the Fahrenheit scale, water
boils at 212F and freezes at 32F.
f/cc - Fibers per cubic
centimeter of air.
Face Velocity - Air velocity at the face
opening required to retain contaminants in the hood or booth.
FACOSH - Federal Advisory Council for Occupational Safety and Health
is a joint management-labor council that advises the Secretary of
Labor on matters relating to the occupational safety and health
of Federal employees.
FDA - U.S. Food and Drug Administration.
Fetal - Pertaining to the fetus.
Fetus - The developing young
in the uterus from the seventh week of gestation until birth.
FFSHC - Field Federal Safety and Health Councils are organized
throughout the country to improve Federal safety and health
programs at the field level and within a geographic location.
FHCP - Federal Hazard Communication Program.
Fibers/cc - Fibers
longer than 5 micrometers and with an aspect ratio equal to or
greater than 3:1 per cubic centimeter.
Fibrosis - An abnormal
thickening of fibrous connective tissue, usually in the lungs.
FIFRA - Federal Insecticide, Fungicide, and Rodenticide Act requires
that certain useful poisons, such as chemical pesticides, sold to
the public contain labels that carry health hazard warnings to
protect users. It is administered by EPA.
First Aid - Emergency
measures to be taken when a person is suffering from overexposure
to a hazardous material, before regular medical help can be
Flammable - A chemical that includes one of the
1. Aerosol, flammable . An aerosol
that, when tested by the method described in 16 CFR 1500.45,
yields a flame projection exceeding 18 inches at full valve opening,
or a flashback (a flame extending back to the valve) at any
degree of valve opening.
2. Gas, flammable. (1) A gas that, at
ambient temperature and pressure,forms a flammable mixture with
air at a concentration of 13 percent by volume or less; or (2) A gas
that, at ambient temperature and pressure, forms a range of
flammable mixtures with air wider than 12 percent by volume,
regardless of the lower limit.
3. Liquid, flammable. 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 mixture.
4. Solid, flammable. A solid, other than a blasting agent or
explosive as defined in 1910.109(a), that is liable to cause
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. A
solid is a flammable solid if, when tested by the method described
in 16 CFR 1500.44, it ignites and burns with a self-sustained
flame at a rate greater than one tenth of an inch per second
along its major axis.
Flashback - Occurs when flame from a
torch burns back into the tip, the torch, or the hose. It is
often accompanied by a hissing or squealing sound with a smoky or
Flashpoint - The minimum temperature at
which a liquid gives off a vapor in sufficient
ignite when tested by the following methods:
Closed Tester (see American National Standard Method of Test for
Flash Point by Tag Closed Tester, Z11.24 -1979 [ASTM D56-79]).
2. Pensky-Martens Closed Tester (see American National Standard
Method of Test for Flash Point by Pensky-Martens Closed Tester,
Z11.7-1979 [ASTM D93-79]).
3. Setaflash Closed Tester (see
American National Standard Method of Test for Flash Point by
Setaflash ClosedTester [ASTM D3278-78]).
Emergency - Any potential occurrence such as, but not limited to,
equipment failure, rupture of containers, or failure of control
equipment which could result in an uncontrolled release of a
hazardous chemical into the workplace.
Formula - The scientific
expression of the chemical composition of a material (e.g., water
is H20, sulfuric acid is H2SO4, sulfur dioxide is SO2).
Fume - A
solid condensation particle of extremely small diameter, commonly
generated from molten metal as metal fume.
g - Gram is a metric
unit of weight. One ounce U.S. (avoirdupois) is about 28.4 grams.
General exhaust - A system for exhausting air containing
contaminants from a general work area. Also see local exhaust .
Genetic - Pertaining to or carried by genes. Heredity.
- The development of the fetus from conception to birth.
Grams per kilogram is an expression of dose used in oral and dermal
toxicology testing to denote grams of a substance dosed per kilogram
of animal body weight. Also see kg (kilogram).
The procedure used to carry an electrical charge to ground through
a conductive path. A typical ground may be connected directly to a
conductive water pipe or to a grounding bus and ground rod. See
Gynecology - The study of the reproductive organs in
Hand Protection - Specific type of gloves or other hand
protection required to prevent harmful exposure to hazardous
Hazard Warning - Words, pictures, symbols, or
combination thereof presented on a label or other appropriate
form to inform of the presence of various materials.
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 an exposed employee. This includes chemicals
which are carcinogens, toxic or highly toxic agents,
reproductive toxins, irritants, corrosives, sensitizes,
hepatotoxins, nephrotoxins, neurotoxins, agents which act on the
hematopoietic (blood-forming) systems, and agents which can
damage the lungs, skin, eyes or mucous membranes.
Hazard Communication Standard is an OSHA regulation issued under 29
CFR Part 1910.1200.
Health Hazard - A chemical for which there is
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 system, and agents which damage the
lungs, skin, eyes, or mucous membranes.
Hematology - The study of blood.
Hematoma - A blood clot under the surface of the skin.
Hematopoietic System - The blood forming mechanism of the human
Hepatotoxin - A substance that causes injury to the liver.
Highly Toxic - A chemical falling within any of the following
1. A chemical with 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
2. A chemical with 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 2 and 3 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 1 hour (or less if death occurs within 1 hour) to
albino rats weighing 200 and 300 grams each.
Operations - Experimental procedures involving the manipulation,
handling or reaction of hazardous chemicals where the potential
for release of gas, vapor, or aerosol contamination is high.
This category includes, but is not limited to (1) rapid exothermic
reactions, (2) transfer of electrostatic powders, (3) heating,
mixing or transfer of volatile chemicals, (4) pressurized
operations where there is a potential for uncontrolled release, and
(5) work involving aerosol generation.
HMIS - Hazardous
Material Information System is a material safety data sheet file
maintained by the Department of Defense and contains material safety
data sheets and transportation data for products purchased by
DOD and GSA. Also refers to the Hazardous Materials
Identification System of the National Paint and Coatings Association
Hormones - Act as chemical messengers to body organs.
Hyperplasia - Increase in volume of a tissue or organ caused by the
growth of new cells.
IARC - International Agency for Research on
Ignitable - Capable of being set afire.
Temperature - Lowest temperature at which a substance will catch
fire, even momentarily, if heat is applied.
Impervious - A
material that does not allow another substance to pass through or
Incompatible - Materials that could cause dangerous
reactions by direct contact with one another.
Taking in by the mouth.
Inhal - see inhalation.
Breathing in of a substance in the form of a gas, vapor, fume, mist,
Inhibitor - A chemical added to another substance to
prevent an unwanted chemical change.
Insol - See insoluble.
Insoluble - Incapable of being dissolved in a liquid.
Intrauterine - Within the uterus.
Irritant - A chemical, which is
not corrosive, but which causes a reversible inflammatory effect
on living tissue by chemical action at the site of contact. A
chemical is a skin irritant if, when tested on the intact skin
of albino rabbits by the methods of 16 CFR 1500.41 for 4 hours
exposure or by other appropriate techniques, it results in an
empirical score of 5 or more. A chemical is an eye irritant if
so determined under the procedure listed in 16 CFR 1500.42 or
other appropriate techniques.
Irritating - An irritating
material, as defined by DOT, is a liquid or solid substance
which, upon contact with fire or when exposed to air, gives off
dangerous or intensely irritating fumes (not including poisonous
materials). See Poison, Class A nd Poison, Class B.
kg - Kilogram
is a metric unit of weight, about 2.2 U.S. pounds. 1000g. Also see
g/kg, g, and mg.
L - Liter is a metric unit of capacity. A U.S.
quart is about 9/10 of a liter.
Label - Notice attached to a
container, bearing information concerning its contents.
Lacrimation - Secretion and discharge of tears.
Lactation - The
secretion of milk by the breasts.
LC - Lethal concentration is
the concentration of a substance being tested that will kill.
LCL - Lethal concentration low. Lowest concentration of a gas or
vapor capable of killing a specified species. Over a specified
LC50 - The concentration of a material in air that will
kill 50 percent of a group of test animals with a single exposure
(usually 1 to 4 hours). The LC50 is expressed as parts of
material per million parts of air, by volume (ppm) for gases and
vapors, or as micrograms of material per liter of air (g/1) or
milligrams of material per cubic meter of air (mg/m3) for dusts
and mists, as well as for gases and vapors.
LD - Lethal dose is
the quantity of a substance being tested that will kill.
Lethal dose low. Lowest administered dose of a material capable of
killing a specified test species.
LD50 - A single dose of
a material expected to kill 50 percent of a group of test animals.
The LD50 dose is usually expressed as milligrams or grams of
material per kilogram of animal body weight (mg/kg or g/kg). The
material may be administered by mouth or applied to the skin.
or LFL - Lower explosive limit, or lower flammable limit, of a vapor
or gas; the lowest concentration (lowest percentage of the
substance in air) that will produce a flash of fire when an
ignition source (heat, arc or flame) is present. At concentrations
lower than the LEL, the mixture is too lean to burn. Also see
Lesion - Any damage to a tissue.
Lfpm - Linear feet per
minute, a unit of air velocity.
Local exhaust - A system for
capturing and exhausting contaminants from the air at the point
where the contaminants are produced (welding, grinding, sanding,
other processes or operations). Also see general exhaust.
Risk Operations - Experimental procedures where the potential for
release of gas, vapor, or aerosol contamination is remote.
Meter is a unit of length in the metric system. One meter is about
m3 - Cubic meter is a metric measure of volume,
approximately 35.3 cubic feet or 1.3 cubic yards.
Malaise - A
feeling of general discomfort, distress, or uneasiness, an
Malignant - Tending to become
progressively worse and to result in death.
Mammary - Pertaining
to the breast.
Mechanical exhaust - A powered device, such as a
motor-driven fan or air steam venturi tube, for exhausting
contaminants from a workplace, vessel, or enclosure.
Filter Respirator - A respirator used to protect against airborne
particulate matter like dusts, mists, metal fume, and smoke.
Mechanical filter respirators do not provide protection against
gases, vapors, or oxygen deficient atmospheres.
Melting point -
The temperature at which a solid substance changes to a liquid
Menorrhagia - Excessive menstruation.
Periodic discharge of blood from the vagina from a non-pregnant
Metabolism - Physical and chemical processes taking place
among the ions, atoms, and molecules of the body.
- The transfer of disease from one organ or part to another not
directly connected with it.
mg - Milligram is a metric unit of
weight which is one-thousandth of a gram.
mg/kg - Milligrams of
substance per kilogram of body weight is an expression of
mg/m3 - Milligrams per cubic meter is a unit
for expressing concentrations of dusts, gases, or mists in air.
Micrometer - A unit of length equal to one-millionth of a meter.
Micron - A unit of length equal to one-millionth of a meter or
1/23,000 of an inch.
Mld - Mild
- Suspended liquid
droplets generated by condensation from the gaseous to the liquid
state, or by breaking up a liquid into a dispersed state, such
as splashing, foaming or atomizing. Mist is formed when a finely
divided liquid is suspended in air.
Mixture - Any combination of
two or more chemicals if the combination is not, in whole or
part, the result of a chemical reaction.
ml - Milliliter is a
metric unit of capacity, equal in volume to 1 cubic centimeter
(cc), or approximately one-sixteenth of a cubic inch. One-thousandth
of a liter.
mmHg - Millimeters (mm) of mercury (Hg) is a unit of
measurement for low pressures or partial vacuums. Molecular
Weight - Weight (mass) of a molecule based on the sum of the atomic
weights of the atoms that make up the molecule.
Million particles per cubic foot is a unit for expressing
concentration of particles of a substance suspended in air.
Exposure limits for mineral dusts (silica, graphite, Portland
cement, nuisance dusts, and others), formerly expressed as mppcf,
are now more commonly expressed in mg/m3.
MSHA - Mine Safety
and Health Administration, U.S. Department of Labor.
Microgram, one-millionth of a gram.
Mutagen - A substance or
agent capable of altering the genetic material in a living cell.
MW - See molecular weight.
N2 - Nitrogen is a colorless,
odorless, and tasteless gas that will not burn and will not
support combustion. The earth's atmosphere (air) is about 78 percent
nitrogen. At higher concentrations, nitrogen can displace oxygen and
become an asphyxiant. See Asphyxiant.
Narcosis - A state of
stupor, unconsciousness, or arrested activity produced by the
influence of narcotics or other chemicals.
Nausea - Tendency to
vomit, feeling of sickness at the stomach.
NCI - National Cancer
Institute is that part of the National Institutes of Health which
studies cancer causes and prevention as well as diagnosis,
treatment, and rehabilitation of cancer patients.
National Fire Protection Association is an international membership
organization which promotes/improves fire protection and prevention
and establishes safeguards against loss of life and property by
Neo - See neoplasia
Neonatal - The first 4 weeks after
Neoplasia - A condition characterized by the presence of
new growths (tumors).
Nephrotoxin - A substance that causes
injury to the kidneys.
Neurotoxin - A material that affects the
nerve cells and may produce emotional or behavioral
Neutralize - To eliminate potential hazards by
inactivating strong acids, caustics, and oxidizers. For example,
acids can be neutralized by adding an appropriate amount of caustic
substance to the spill.
ng - nanogram, one-billionth of a
NIOSH - National Institute for Occupational Safety and
Health, U.S. Public Health Service, U.S. Department of Health and
Human Services (DHHS), among other activities, tests and
certifies respiratory protective devices and air sampling
detector tubes, recommends occupational exposure limits for various
substances, and assists OSHA and MSHA in occupational safety and
health investigations and research.
NOC - Not otherwise
Non-flammable - Not easily ignited, or if ignited, not
Non-Sparking Tools - Tools made from
beryllium-copper or aluminum-bronze greatly reduce the
possibility of igniting dusts, gases, or flammable vapors. Although
these tools may emit some sparks when striking metal, the sparks
have a low heat content and are not likely to ignite most
NPIRS - National Pesticide Information
Retrieval System is an automated data base operated by Purdue
University containing information on EPA registered pesticides,
including reference file material safety data sheets.
National Response Center is a notification center which must be
called when significant oil or chemical spills or other
environment-related accidents occur. The toll-free telephone
number is 1-800-424-8802.
NOx - Oxides of nitrogen which are
undesirable air pollutants. NOx emissions are regulated by EPA
under the Clean Air Act.
NTP - National Toxicology Program. The
NTP publishes an Annual Report on Carcinogens.
Exposure Limits - Maximum allowable concentrations of toxic
substances in workroom air to protect workers who are exposed to
toxic substances over a lifetime.
Odor - A description of the
smell of the substance.
Odor Threshold - The lowest concentration
of a substance's vapor, in air, that can be smelled.
- Relating to the sense of smell.
Oral - Used in or taken into
the body through the mouth.
OFAP - Office of Federal Agency
Programs is the organizational unit of OSHA which provides Federal agencies with guidance to develop and implement occupational
safety and health programs for Federal employees.
Toxicity - Adverse effects resulting from taking a substance into
the body by mouth. Ordinarily used to denote effects in
Organic Peroxide - An organic compound
that contains the bivalent -0-0 structure and may be considered a
structural derivative of hydrogen peroxide where one or both of
the hydrogen atoms has been replaced by an organic radical.
Organogenesis - The secretion of tissues into different organs in
OSHA - Occupational Safety and Health
Administration, U.S. Department of Labor.
Ovary - The female
sex gland in which ova are formed.
Overexposure - Exposure to a
hazardous material beyond the allowable exposure levels.
Ovulation - The process in which an ovum is discharged from an
Ovum - Egg.
Oxidation - In a literal sense,
oxidation is a reaction in which a substance combines with oxygen provided by an oxidizer or oxidizing agent.
Oxidizer - A
chemical other than a blasting agent or explosive that initiates or
promotes combustion in other materials, causing fire either by
itself or through the release of oxygen or other gases.
Oxidizing Agent - A chemical or substance that brings about an
oxidation reaction. The agent may (1) provide the oxygen to the
substance being oxidized (in which case the agent has to be
oxygen or contain oxygen), or (2) it may receive electrons being
transferred from the substance undergoing oxidation (chlorine is
a good oxidizing agent for electron-transfer purposes, even
though it contains no oxygen).
Papanicolaou Smear - Test most
commonly used to detect cancer of the uterus and cervix.
Pathologic - Pertaining to or caused by disease.
Scientific study of alterations produced by disease.
Permissible exposure limit is an exposure limit established by
OSHA'S regulatory authority. It may be a time weighted average
(TWA) limit or a maximum concentration exposure limit.
Percent Volatile - Percent volatile by volume is the percentage of a
liquid or solid (by volume) that will evaporate at an ambient
temperature of 70F (unless some other temperature is specified).
Examples: butane, gasoline, and paint thinner (mineral spirits) are
100 percent volatile; their individual evaporation rates vary,
but, in time, each will evaporate completely.
pH - The symbol
relating the hydrogen ion (H-) concentration to that of a given
standard solution. A pH of 7 is neutral. Numbers increasing from 7
to 14 indicate greater alkalinity. Numbers decreasing from 7 to
0 indicate greater acidity.
Physical Hazard - Means a chemical
for which there is scientifically valid evidence that it is a
combustible liquid, a compressed gas, explosive, flammable, and
organic peroxide, an oxidizer, pyrophoric, unstable (reactive)
or water- reactive.
Placenta - A structure that grows on the wall
of the uterus during pregnancy, through which the fetus is
PMCC - Pensky-Martens Closed Cup. See flashpoint.
Pneumoconiosis - A condition of the lung in which there is permanent
deposition of particulate matter and the tissue reaction to its
presence. It may range from relatively harmless forms of iron
oxide deposition to destructive forms of silicosis.
A - A DOT term for extremely dangerous poison, poisonous gases or
liquids that, in very small amounts, either as gas or as vapor of
the liquid , mixed with air, are dangerous to life. Examples:
phosgene, cyanogen, hydrocyanic acid, nitrogen peroxide.
Class B - A DOT term for liquid, solid, paste or semi-solid
substances, other than Class A poisons or irritating materials,
that are known (or presumed on the basis of animal tests) to be
so toxic to humans that they are a hazard to health during
Polymerization - A chemical reaction in which
one or more small molecules combine to form larger molecules. A
hazardous polymerization is such a reaction that takes place at a
rate that releases large amounts of energy. If hazardous
polymerization can occur with a given material, the material
safety data sheet usually will list conditions that could start the
reaction and, since the
material usually contains a
polymerization inhibitor, the length of time during which the
inhibitor will be effective.
ppm - Parts per million is the
concentration of a gas or vapor in air, parts (by volume) of the
gas or vapor in a million parts of air; also the concentration of a
particular in a liquid or solid.
ppb - Parts per billion is
the concentration of a gas or vapor in air, parts (by volume) of
the gas or vapor in a billion parts of air. Usually used to express
extremely low concentrations of unusually toxic gases or vapors;
also the concentration of a particular substance in a liquid or
Prenatal - Preceding birth.
Practices and Equipment - Those laboratory procedures,
engineering/administrative controls, work practices and protective
clothing and equipment used to minimize employee exposure to
psi - Pounds per square inch (for material
safety data sheet purposes) is the pressure a material exerts on
the walls of a confining vessel or enclosure. For technical
accuracy, pressure must be expressed as psig (pounds per square
inch gauge) or psia (pounds per square inch absolute; that is,
gauge pressure plus sea level atmospheric pressure, or psig plus
approximately 14.7 pounds per
square inch). Also see mmHg.
- See pulmonary.
Pulmonary - Relating to, or associated with, the
Pulmonary Edema - Fluid in the lungs.
Pyrophoric - A
chemical that will ignite spontaneously in air at a temperature of
13F (54.4C) or below.
RCRA - Resource Conservation and Recovery
Act is environmental legislation aimed at controlling the
generation, treating, storage, transportation and disposal of
hazardous wastes. It is administered by EPA.
chemical transformation or change. The interaction of two or more
substances to form new substances.
Reactive - See Unstable.
Reactivity - Chemical reaction with the release of energy.
Undesirable effects, such as pressure buildup, temperature
increase, formation of noxious, toxic or corrosive by-products
may occur because of the reactivity of a substance to heating
burning, direct contact with other materials, or other
conditions in use or in storage. Reducing agent - In a reduction
reaction (which always occurs simultaneously with an oxidation
reaction) the reducing agent is the chemical or substance which
combines with oxygen or
(2) loses electrons to the reaction. See
Reproductive Toxin - A chemical which affects the
reproductive system and may produce chromosomal damage (mutation)
and/or adverse effects on the fetus (teratogenesis). For
the purposes of this guidance, any chemical with a mutagenic or
teratogenic quotation in the Registry of Toxic Effects of
Chemical Substances (RTECS) shall be considered a reproductive
Respiratory protection - Devices that will protect the
wearer's respiratory system from overexposure by inhalation to
airborne contaminants. Respiratory protection is used when a
worker must work in an area where he/she might be exposed to
concentration in excess of the allowable exposure limit.
Respiratory system - The breathing system that includes the lungs
and the air passages (trachea or windpipe, larynx, mouth, and
nose) to the air outside the body, plus the associated nervous
and circulatory supply.
Routes of Entry - The means by which a
material may gain access to the body, for example, inhalation,
ingestion, and skin contact.
RTECS - The Registry of Toxic
Effects of Chemical Substances
Sarcoma - A tumor which is often
Self-Contained Breathing Apparatus - A respiratory
protection device that consists of a supply or a means of
respirable air, oxygen, or oxygen-generating material, carried by
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
SETA - Setaflash Closed Tester. See flashpoint.
- Standard Industrial Classification
Silicosis - A disease of the
lungs caused by the inhalation of silica dust.
Skn - Skin
- A notation (sometimes used with PEL or TLV exposure data) which
indicates that the stated substance may be absorbed by the skin,
mucous membranes, and eyes either airborne or by direct contact
and that this additional exposure must be considered part of the
total exposure to avoid exceeding the PEL or TLV for that
Skin Absorption - Ability of some hazardous chemicals
to pass directly through the skin and enter the bloodstream. Skin
Sensitizer - See Sensitizer. Skin Toxicity - See Dermal
Toxicity. SOx - Oxides of sulfur.
Solubility - Amount of a
substance that can be dissolved in another substance.
water - A term expressing the percentage of a material (by
weight) that will dissolve in water at ambient temperature.
Solubility information can be useful in determining spill cleanup
methods and re-extinguishing agents and methods for a material.
Solvent - A substance, usually a liquid, in which other substances
are dissolved. The most common solvent is water.
Species - On
the material safety data sheets, species refers to the test animals,
usually rats, mice, or rabbits, used to obtain the toxicity test
Specific Chemical Identity - The chemical name,
Chemical Abstracts Service (CAS) Registry Number, or any precise
chemical designation of a substance.
Specific Gravity - The
weight of a material compared to the weight of an equal volume of
water is an expression of the density (or heaviness) of a
material. Insoluble materials with specific gravity of less than
1.0 will float in (or on) water. Insoluble materials with specific
gravity greater than 1.0 will sink in water. Most (but not all)
flammable liquids have specific gravity less than 1.0 and, if
not soluble, will float on water, which is an important
consideration for fire suppression.
Spill or Leak Procedures
- The methods, equipment, and precautions that should be used to
control or clean up a leak or spill.
Splash Proof Goggles - Eye
protection made of a noncorrosive material that fits snugly
against the face, and has indirect ventilation ports.
Spontaneously Combustible - A material that ignites as a result of
retained heat from processing, or which will oxidize to generate
heat and ignite, or which absorbs moisture to generate heat and
Squamous - Scaly or platelike.
Stability - The ability
of a material to remain unchanged. For material safety data sheet
purposes, a material is stable if it remains in the same form under
expected and reasonable conditions of storage or use. Conditions
which may cause instability (dangerous change) are stated; for
example, temperatures above 150F; shock from dropping.
Short Term Exposure Limit (ACGIH terminology). See TLV.
- Narrowing of a body passage or opening.
Steroids - A complex
molecule among which are the male and female sex hormones.
Subcutaneous - Beneath the layers of the skin.
Respirators - Air line respirators or self-contained breathing
Suspect Carcinogen - Substance that might cause cancer
in humans but has not been proven to do so.
Sys - System or
Systemic Poison - A poison which spreads throughout the
body, affecting all body systems and organs. Its adverse effect
is not localized in one spot or area.
Systemic Toxicity -
Adverse effects caused by a substance which affects the body in a
general rather than local manner.
Synonym - Another name or
names by which a material is known. Methyl alcohol, for example,
is known as methanol or wood alcohol.
Target Organ Effects - The
following is a listing of target organs, toxicants specific for
these organs, and some of the toxic effects produced by these
agents. These examples are presented to illustrate the diversity
of hazards employers must consider in the workplace and are not
intended as a complete listing of such agents and their target
Target Organ Toxin - A toxic
substance that attacks a specific organ of the body. For example,
overexposure to carbon tetrachloride can cause liver damage.
- Tag (Tagliabue) Closed Cup. See flashpoint.
TCL - Toxic
concentration low. Lowest concentration of a gas or vapor capable of
producing a defined toxic effect in a specified test species over a
TDL - Toxic dose low. Lowest administered dose
of a material capable of producing a defined toxic effect in a
specified test species.
Temp - Temperature.
Ter - See
Teratogen - A substance or agent, exposure to which by
a pregnant female can result in malformations in the fetus.
Tfx - Toxic effect(s).
TLV - Threshold Limit Value is a term used
by ACGIH to express the airborne concentration of material to
which nearly all persons can be exposed day after day without
adverse effects. ACGIH expresses TLVs in three ways:
TLV-TWA: The allowable Time Weighted Average concentration for a
normal 8-hour workday or 40-hour workweek.
2. TLV-STEL: The
Short-Term Exposure Limit, or maximum concentration for a continuous
15-minute exposure period (maximum of four such periods per day,
with at least 60 minutes between exposure periods, and provided
the daily TLV-TWA is not exceeded).
3. TLV-C: The ceiling
exposure limit, the concentration that should not be exceeded
TOC - TAG Open Cup. See flashpoint.
Torr - A unit of pressure, equal to 1/760 atmosphere.
Toxic - A
chemical falling within any of the following categories:
1. A chemical with 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 1,000 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.
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 1 hour) to albino
rats weighing between 200 and 300 grams each.
- Any substance which can cause acute or chronic injury to the human
body, or which is suspected of being able to cause diseases or
injury under some conditions.
Toxicant - Any substance producing
a toxic effect.
Toxicity - The sum of adverse effects resulting
from exposure to a material, generally by the mouth, skin, or
Trade Name - The trademark name or commercial
trade name for a material or product.
Transplacental - An
agent that causes physical defects in the developing embryo.
TSCA - Toxic Substances Control Act (Federal Environmental
Legislation administered by EPA) regulates the manufacture,
handling, and use of materials classified as toxic substances.
TWA - Time-Weighted Average exposure is the airborne concentration
of a material to which a person is exposed, averaged over the
total exposure time, generally the total workday (8 hours). Also
UEL or UFL - Upper explosive limit or upper flammable
limit of a vapor or gas; the highest concentration (highest
percentage of the substance in air) that will produce a flash of
fire when an ignition source (heat, arc, or flame) is present. At
higher concentrations, the mixture is too rich to burn. Also see
Unstable - Tending toward decomposition or other unwanted
chemical change during normal handling or storage.
Reactive - A chemical that, in the pure state, or as produced or
transported, will vigorously polymerize, decompose, condense, or
become self- reactive under conditions of shocks, pressure, or
USDA - U.S. Department of Agriculture.
Uterus - A
muscular organ which holds and nourishes the growing fetus.
- The gaseous form of a solid or liquid substance as it evaporates.
Vapor density - The weight of a vapor or gas compared to the
weight of an equal volume of air is an expression of the density
of the vapor or gas. Materials lighter than air have vapor densities
less than 1.0 (examples: acetylene, methane, hydrogen).
Materials heavier than air (examples: propane, hydrogen sulfide,
ethane, butane, chlorine, sulfur dioxide) have vapor densities
greater than 1.0. All vapors and gases will mix with air, but
the lighter materials will tend to rise and dissipate
confined). Heavier vapors and gases are likely to concentrate in low
places along or under floors, in sumps, sewers, and manholes, in
trenches and ditches where they may create fire or health
Vapor pressure - The pressure exerted by a saturated vapor
above its own liquid in a closed container. When quality control
tests are performed on products, the test temperature is usually
100F, and the vapor pressure is expressed as pounds per square
inch (psig or psia), but vapor pressures reported on material
safety data sheets are in millimeters of mercury (mmHg) at 68F
(20C), unless stated otherwise. Three facts are important to
1. Vapor pressure of a substance at 100F will
always be higher than the vapor pressure of the
substance at 68F
2. Vapor pressures reported on material safety data sheets
in mmHg are usually very low pressures;
760 mm Hg is equivalent
to 14.7 pounds per
3. The lower the boiling point
of a substance, the higher its vapor pressure.
See General Exhaust, Local Exhaust, and Mechanical Exhaust.
Vermiculite - An expanded mica (hydrated magnesium-aluminum-iron
silicate) used as sorbent for spill control and cleanup.
Volatility - A measure of how quickly a substance forms a vapor at
Viscosity - The tendency of a fluid to
resist internal flow without regard to its density.
Disposal Methods - Proper disposal methods for contaminated
material, recovered liquids or solids, and their containers.
Water-Reactive - A chemical that reacts with water to release a gas
that is either flammable or presents a health hazard.
Area - A room or defined space in a workplace where hazardous
chemicals are produced or used, and where employees are present.
Workplace - An establishment at one geographical location containing
one or more work areas.