| Acid |
A substance that produces hydrogen ions (H+) in aqueous solutions. An
acid will destroy human tissue on contact. The pH values of acids are
between 0 and 6. Strong acids have a lower pH and are more corrosive
than weak acids. Examples of strong acids include hydrochloric acid, nitric
acid, and phosphoric acid. |
| Acute Effects |
Adverse symptoms that occur immediately or shortly after an exposure to
a chemical. Common symptoms of acute exposure include headache, dizziness,
or nausea. |
| Acute Toxicity |
Acute effects resulting from a single dose of, or exposure to, a substance. |
| Anesthetic |
A chemical that causes a total or partial loss of sensation. Overexposure to
anesthetics can cause impaired judgment, dizziness, drowsiness, headache,
unconsciousness, and even death. Examples include alcohol, paint
remover, and degreasers. |
| Antidote |
A remedy to relieve, prevent, or counteract the effects of a poison. |
| Aquatic Toxicity |
The adverse effects of marine life that result from being exposed to a
toxic substance. |
| Asphyxiate |
A vapor or gas that can cause unconsciousness or death by suffocation due
to lack of oxygen. Asphyxiation is an extreme hazard when working in enclosed
spaces. |
| Asymptomatic |
Showing no symptoms. |
| Base |
A substance that produces hydroxide ions (OH-) in aqueous solution. The
pH values of bases are between 8 and 14. Strong bases have a higher pH
and are more corrosive than weak bases. Examples of strong bases include
sodium hydroxide and ammonium hydroxide. Bases are also referred to as
alkalis or caustic materials and are corrosive to human tissue. |
| Biodegradable |
Capable of being broken down into non-harmful products by the action of living things. |
| Carcinogen |
A substance or agent that has been demonstrated to cause or produce cancer in
mammals, including humans. |
| CAS |
Chemical Abstracts Service is an organization under the American Chemical
Society. CAS Numbers are used to identify specific chemicals or mixtures. |
| Caustic |
Any strongly alkaline material that produces either corrosion or irritation to living
tissue. See Base. |
| Ceiling Limit |
The maximum allowable human exposure limit for an airborne substance which is not
to be exceeded even momentarily. |
| CERCLA |
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. |
| CFR |
Code of Federal Regulations. A collection of the regulations that have been promulgated
under United States Law. |
| Chronic Effect |
Adverse symptoms of chemical exposure that develop slowly over a long period of time due to
repeated long-term exposure to a substance. Examples include cancer or damage to certain
internal organs. |
| Chronic Exposure |
Repeated long-term contact with a substance. |
| Chronic Toxicity |
Adverse effects resulting from repeated doses of or exposures to a substance over a
long period of time. |
| Combustible |
Able to catch on fire or burn. They do not ignite as easily as flammable
liquids. However, combustible liquids can be ignited under certain
circumstances, and must be handled with caution. |
| Compressed Gas |
| 1) |
A gas or mixture of gases having, in a container, an absolute pressure exceeding
40 pounds per square inch (psi) at 70°F (21.1°C); or
|
| 2) |
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
|
| 3) |
A liquid having a vapor pressure exceeding 40 psi at 100°F (37.8°C) as
determined by ASTM D-323-72 |
|
| Concentration |
The relative amount of a substance when combined or mixed with other substances. |
| Corrosive Material |
Any solid, liquid, or gas that burns, irritates, or destroys organic tissues such as the skin,
lungs, stomach. Corrosives can also destroy metal and other building materials. |
| Cryogenic Liquid |
Severely cold (-60ºC to -270ºC) and pressurized liquids. They present
explosion hazards and can cause damage to living tissue. |
| Decomposition |
Breakdown of a material or substance by heat, chemical reaction, electrolysis, decay,
or other processes into parts, elements, or simpler compounds. |
| Density |
The mass (weight) per unit volume of a substance. Usually given in pounds per
gallon or grams per milliliter. |
| Dermal Toxicity |
Adverse effects resulting from skin exposure to a substance. |
| Dispensability |
Able to scatter, spread about or distribute widely. |
| Evaporation Rate |
The rate at which a material will vaporize (evaporate) when compared to the known rate of
vaporization of a standard material. |
| Explosive |
A chemical that causes a sudden, almost instantaneous release of pressure, gas, and
heat when subjected to sudden shock, pressure, or high temperature. |
|
Extremely Hazardous Substance |
A substance listed under section 302(a)(2) of SARA Title III. Under Title III, revisions
to the list must take into account, a chemical's toxicity, reactivity, volatility,
dispensability, combustibility or flammability. |
| 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. |
| Flammable |
A chemical that falls into one of the following categories:
|
| 1) |
Liquid: A liquid with a flashpoint below 100°F (37.8°C).
|
| 2) |
Solid: A solid, other than a blasting agent or explosive, that
is able 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 hazard.
|
| 3) |
Gas: A gas that, at ambient temperature and pressure, forms a
flammable mixture with air at a concentration of 13 percent by volume or
less.
|
| 4) |
Aerosol: A chemical substance or mixture dispensed from its
container as a spray or mist by a propellant under pressure 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 at
any degree of valve opening.
|
|
| Flashpoint |
The minimum temperature at which a liquid gives off vapor in sufficient concentration to
ignite. Used to determine how flammable a liquid is. |
| Hazardous Chemical |
Any chemical whose presence or use is a physical hazard or health hazard. |
| 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. |
| Highly Toxic |
A chemical in any of the following categories:
|
| 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 grams each.
|
| 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 (LD50)
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 between 200 and 300 grams each.
|
|
Accidental release or exposure to a highly toxic chemical can cause serious injury or death. |
|
| Ignitable |
Capable of being set on fire. |
| Inhibitor |
A chemical added to another substance to prevent an unwanted chemical change. |
| Insoluble |
Not capable of being dissolved in a liquid. |
| Irritant |
A chemical, which is not corrosive, that causes a reversible inflammatory effect on living
tissue by chemical action at the site of contact (skin, eyes or mucous membranes). |
| Lacrimation |
Abnormal or excessive production of tears as a result of exposure of the eyes to
an irritant. |
| Melting Point |
The temperature at which a solid substance changes to a liquid state. |
| Mixture |
A heterogeneous association of substances where the various individual substances retain
their identities and can usually be separated by mechanical means. Includes solutions or
compounds but does not include alloys or amalgams. |
| Nephrotoxins |
Chemicals that cause kidney damage. |
| Neurotoxins |
Chemicals that produce their primary toxic effects on the nervous system. |
| Nonflammable |
Not easily ignited, or if ignited, not burning rapidly. |
| Organic Peroxide |
An organic compound that contains the bivalent-0-0 structure and that may be
considered to be a structural derivative of hydrogen peroxide where one
or both of the hydrogen atoms has been replaced by an organic radical. |
| Oral Toxicity |
Adverse effects resulting from taking a substance into the body by mouth. |
| Oxidizer |
A chemical other than a blasting agent or explosive that initiates or promotes
combustion in other materials, thereby causing fire either of itself or
through the release of oxygen or other gases. |
| Pathologic |
Pertaining to or caused by disease. |
| 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 great
alkalinity. Numbers decreasing from 7 to 0 indicate greater acidity. |
| Physical Hazard |
A chemical for which there is scientifically valid evidence that it is a combustible
liquid, a compressed gas, explosive, flammable, an organic peroxide, an
oxidizer, pyrophoric, unstable (reactive) or water-reactive. |
| 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. |
| Pulmonary |
Relating to, or associated with, the lungs. |
| Pyrophoric |
A chemical substance that will ignite spontaneously in air at a temperature of 130ºF
(54.4ºC) or below. |
| Radioactivity |
Nuclear transformation, either by natural or artificial means, resulting in emission
of energy in the form of alpha, beta or gamma rays. |
| Reaction |
A chemical transformation or change. The interaction of two or more substances to
form new substances. |
| Reactivity |
A substance's susceptibility to undergoing a chemical reaction or change
that may result in dangerous side effects, such as explosions, burning,
and corrosive or toxic emissions. The conditions that cause the
reaction, such as heat, other chemicals, and dropping, will usually be
specified as "Conditions to Avoid" when a chemical's
reactivity is discussed on a MSDS. |
| 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. |
| Solvent |
A substance, usually a liquid, in which other substances are dissolved. The most
common solvent is water. |
| Spontaneously Combustible |
Capable of catching fire without an ignition source. Can occur due to oxidation
in air or by internal heat buildup. |
| Systemic Poison |
A poison that 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 that affects the body in a general rather
than local manner. |
| Toxic Substance |
Any substance that 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. |
| Toxicity |
The degree of poisoning that can occur from exposure to a chemical. |
| Unstable (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 shock, pressure, or temperature. |
| Vapor |
The gaseous form of a solid or liquid substance as it evaporates. |
| Viscosity |
The tendency of a fluid to resist internal flow without regard to its density. |
| Volatility |
A measure of how quickly a substance forms a vapor at ordinary temperatures.
Chemicals with higher vapor pressures and lower boiling points will have higher
volatilities and will evaporate quicker. |
| Water Reactive |
A chemical that reacts with water to release a gas that is either flammable or
presents a health hazard. |
