| Absorption |
Penetration of a substance
into another substance. |
| Acidosis |
Acid poisoning in the
blood. |
| Acid |
A chemical which has the
ability to neutralise an alkali to form a salt. Certain acids react vigorously with
metals, releasing hydrogen gas. Acids may also be corrosive to the skin, eyes and mucous
membranes, especially in concentrated form. Acid turns blue litmus paper red. Sulphuric,
hydrochloric and nitric acid are common examples. |
| Acute Effect |
An adverse effect on a
human or animal, following a single dose or short exposure with symptoms developing
rapidly. |
| Acute Toxicity |
The toxic effects resulting
from a single dose or short exposure to a substance. |
| Adsorption |
Condensation of gases,
liquids or dissolved substances on the surfaces of solids. |
| ADN/ADNR |
European regulations for
inland waterway transport of hazardous goods. |
| ADR |
European regulations for
road transport of hazardous goods. |
| Aerobe |
Micro-organisms that
survive in the presence of oxygen (air). |
| Aerosol |
An airborne mist of a solid
or liquid substance. |
| Alcohol Resistant Foam |
Medium to fight fires of
highly flammable, water soluble substances. It has less mechanical strength than other
foams. |
| Aliphatics |
Refers to an open-chain or
fatty series of hydrocarbons. Usually applied to petroleum products derived from a
paraffin or olefin base and having a straight or branched chain molecular structure.
Substances such as ethane and ethylene are typical aliphatic hydrocarbons. Also see
"Aromatic". |
| Alkali |
A compound that has the
ability to neutralize an acid to form a salt. A substance which is somewhat irritating or
corrosive to the skin, eyes and mucous membranes. Turns red litmus paper to blue. Common
strong alkalis are sodium and potassium hydroxide. |
| Allergic Reaction |
An abnormal physiological
response in a person who has become hypersensitive to a specific substance. Some forms of
dermatitis and asthma may be caused by allergic reactions to chemicals. |
| Anaerobe |
Micro-organisms that
survive without oxygen (air). |
| Anaesthetic Effect |
The temporary loss of
feeling which reduces the ability to feel pain and/or other sensations. |
| Antidote |
An agent that neutralizes
or counteracts the effects of a poison. |
| Aromatics |
The name
"aromatics" is derived from their rather pleasant odour. The chemical may,
however, be carcinogenic. Refers to petroleum products which have a ring molecular
structure. Aromatics tend to burn with black, smoky flames. Benzene, toluene and xylene
are the principal aromatics. |
| Asphyxiant |
A vapour or gas which can
cause unconsciousness or death by suffocation (lack of oxygen). |
| Aspiration Hazard |
The danger of drawing a
fluid into the lungs and causing chemical pneumonia or other inflammatory response. |
| ASTM |
American Society for
Testing Materials. |
| Auto-ignition
Temperature |
The approximate lowest
temperature at which a flammable gas or vapour-air mixture will spontaneously ignite
without spark or flame. |
| Bar |
Unit of pressure.
Normal atmospheric pressure = 1.013 bar (=1013 mbar) |
| Bioaccumulation |
The process in and by which
chemical substances are accumulated in living organisms. |
| Biodegradation |
Natural decomposition of a
substance via biological processes. |
| Boiling Point |
The temperature at which a
liquid changes to a vapour state, at a given pressure. For mixtures, the initial
"boiling point" or the "boiling range" may be given. |
| Burns |
An injury to skin tissue
caused by heat, chemicals, electricity or irradiation. |
| °C |
Degrees Celsius or
Centigrade. |
| "CL" |
The maximum allowable human
exposure limit for an airborne substance; not to be exceeded, even momentarily. Also see
"PEL" and "TLV". |
| Carcinogen |
A substance or agent
capable of causing cancer. |
| C.A.S. Number |
A number assigned to
specific chemicals by the Chemical Abstracts Service. (An organization operated by the
American Chemical Society which indexes chemical information). |
| Caustic |
A compound that strongly
irritates, burns, corrodes or destroys living tissue. |
| cc |
Cubic centimetre. A volume
measurement in the metric system, equal in capacity to one millilitre (ml). |
| Chemical Pneumonitis |
Inflammation of the lungs,
caused by inhalation or aspiration of an irritating substance. |
| Cocarcinogen |
Material which potentiates
the effect of a carcinogen. |
| COC |
Cleveland Open Cup: a flash
point test method. |
| Coma |
A state of deep
unconsciousness from which one cannot be aroused, even by powerful stimulation. |
| Combustible |
A substance capable of
fuelling a fire. |
| Compatibility |
Ability of two or more
substances to mix without objectionable changes in their physical or chemical properties. |
| Condensation |
Change in physical state of
a substance from vapour to liquid (or solid) form. |
| Container |
Any bag, barrel, bottle,
box, can, drum, reaction vessel, storage tank, road- or rail-tanker, or the like that
contains a hazardous chemical. Pipes or piping systems are not considered to be
containers. |
| Corneal/Conjunctival
Burns |
Burns to the transparent
membrane covering the eyeball and lining of the eyelids. |
| Corrosive |
A material that causes
visible destruction or irreversible alterations in tissue at the site of contact. |
| Cutaneous |
Of or relating to skin. |
| Decomposition |
Breakdown of a material or
substance (by heat, chemical reaction, electrolysis, decay or other processes). |
| Defatting |
The removal of natural oils
from the skin by a fat-dissolving solvent. |
| Deflagration |
To burn rapidly with
intense heat and sparks being given off. |
| Dehydration |
The removal of water from a
substance. A condition that results from an excessive loss of body fluids. Abnormal
depletion of bodily water. |
| Dermal |
Of or pertaining to the
skin. |
| Dermal Toxicity |
Toxic effects resulting
from skin exposure to a substance. |
| Dermal Sensitisation |
A hypersensitivity response
of the skin resulting from repeated contact with an allergenic substance. |
| Dermatitis |
Inflammation of the skin
often characterised by oozing, redness and itching. |
| Detonation |
To explode with sudden
force. |
| Downwind |
In the direction toward
which the wind is blowing in relation to the object or area in question. |
| Dry Chemical Powder |
A powdered fire
extinguishing agent. |
| Dusts |
Solid particles suspended
in air generated by a mechanical process such as crushing, grinding, abrasion or blasting. |
| Epidemiology |
An allied health science
that is concerned with the determination of the specific causes of outbreaks of infection,
disease, and health effects. |
| Eschar |
A thick crusting or
scabbing on the skin. |
| Explosive |
A chemical that causes a
sudden, almost instantaneous release of pressure, gas and heat when subjected to sudden
shock, pressure or high temperature. |
| Explosive Limits |
The range of concentration
of a flammable gas or vapour (percent by volume in air) in which explosion can occur if an
ignition source is present. |
| Exposure Limit |
Limit set to minimise
occupational exposure to a hazardous substance. |
| Extinguishing Agents |
Media suitable for
controlling or putting out a fire, when properly applied. |
| °F |
Degrees Fahrenheit: T(°C)
= [T(°F)-32] x 5/9 |
| Fatal |
Causing death; deadly. |
| Fibrosis |
A condition marked by the
abnormal increase in the amount of fibrous connective tissue in an organ or tissue. |
| Fire Point |
The lowest temperature at
which a material can evolve vapours fast enough to support continuous combustion. |
| First Degree Burn |
A mild burn, characterized
by pain and reddening of the skin. |
| Flammable |
A material which is easily
ignited. |
| Flash Point |
The minimum temperature at
which a liquid gives off sufficient vapour to form an ignitable mixture with air. |
| Foetal |
Of or pertaining to a
foetus. The unborn young of an animal while still in the uterus. |
| Freezing Point |
The temperature at which a
liquid substance changes to a solid state. |
| Frostbite |
Damage to tissues resulting
from exposure to extreme cold or contact with extremely cold liquids or objects. |
| Frothing |
Bubbles formed on or in a
liquid; foaming. |
| Fumes |
Fumes are formed by
processes such as sublimation or condensation and is the term generally applied to
particles condensed from the gaseous state (e.g. metal fumes, polymer fumes). |
| Gas |
May be compressed,
liquefied or dissolved under pressure. |
| Gastric Lavage |
The irrigation or washing
out of the stomach by means of a gastric tube. |
| Gastrointestinal
Disturbances |
A general term used to
describe any symptoms referrable to the stomach or intestines such as nausea, vomiting,
cramping and/or diarrhoea. |
| g/kg |
Grams per kilogram. An
expression of dosage used in toxicology testing, to indicate the grams of substance dosed
per kilogram of animal body weight. |
| Hazard Warning |
Any words, pictures,
symbols, or combination thereof appearing on a label or other appropriate form of warning
which convey the hazards of the chemical(s) in the container(s). |
| Hazardous Chemical |
Any chemical which is a
physical, health or environmental hazard. |
| Health Hazard |
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. |
| Hydrocarbons |
Compounds composed solely
of carbon and hydrogen. |
| Hygroscopic |
Capacity to absorb water. |
| ICAO/IATA |
International regulations
for air transport of hazardous goods. |
| IMO/IMDG |
International regulations
for maritime transport of hazardous goods. |
| Ignition Source |
Anything that provides
beat, spark or flame sufficient to cause combustion/explosion. |
| Impervious |
Incapable of being
penetrated by a substance. |
| Inhibitor |
A substance which is added
to another substance to prevent an unwanted chemical reaction from occurring. |
| Irritant |
A substance which will
cause an inflammatory response or reaction of the eye, skin or respiratory system. |
| LC50 |
Lethal Concentration 50%;
the concentration of a material in air which on the basis of laboratory tests, is expected
to cause 50% mortality in a group of test animals when administered as a single exposure. |
| LD50 |
Lethal Dose 50%; a single
dose of material which, on the basis of laboratory tests, is expected to cause 50%
mortality in a group of test animals when administered as a single exposure. |
| LEL or LFL |
Lowest Explosive Limit or
Lower Flammable Limit. |
| Melting Point |
The temperature at which a
solid substance changes to a liquid state. |
| mg/kg |
Milligrams per kilogram. An
expression of toxicological dose. |
| mg/m³ |
Milligrams per cubic metre;
a unit for measuring concentrations of particulates or gases in the air (a weight per unit
volume). |
| Mist |
Liquid droplets suspended
in the air. |
| mm Hg |
Millimetres (mm) of mercury
(Hg). Unit of pressure. Normal atmospheric pressure = 760 mm Hg. |
| Mucous Membrane |
A thin layer of
mucous-secreting tissue covering a body surface or lining an organ. For example : the
nose, stomach, intestines and bronchial tubes. |
| Mutagen |
A substance or agent
capable of altering the genetic material of a living cell. |
| Nausea |
An unpleasant sensation,
often culminating in vomiting. |
| Neutralise |
To render chemically
neutral or harmless; neither acid nor base. |
| Non-combustible |
A material which will not
ignite, burn, support combustion or release flammable vapours when subjected to heat or
fire. |
| N.O.S. |
Abbreviation for "Not
Otherwise Specified". Used as a collective entry in transport regulations to which
substances may be assigned if they are not mentioned by name. |
| Ocular |
Affecting the eye. |
| Oedema |
The presence of abnormally
large amounts of fluid in the tissue spaces of the body. May be visible as swelling of a
body part such as the legs or face. |
| Olfactory |
Relating to the sense of
smell. |
| Oral |
Affecting the mouth. |
| Oral LD50 |
Oral Lethal Dose 50%; the
concentration of a substance, orally administrated which will produce 50 percent mortality
in the animals tested. |
| Oral Toxicity |
Adverse effects which
result from taking a substance into the body via the mouth. |
| Oxidising Agent |
A chemical other than a
blasting agent or explosive that initiates or promotes oxidation in other materials,
possibly causing fire either of itself or through the release of oxygen or other gases. |
| Pa |
Pascal : unit of pressure.
Normal atmospheric pressure = 101.3 kPa |
| Paralysis |
Partial or complete loss of
function of a sense (such as smell) or partial or complete loss of motor function of a
part of the body. |
| Partition Coefficient
(n-octanol/water) |
Distribution coefficient
used to evaluate the harm the substance can cause to environment. Higher values indicate
higher chance of accumulation of the substance in biological material. |
| Pathological Changes |
Abnormal structural and/or
functional changes in a body caused by a diseased state or exposure to a toxic chemical. |
| PEL |
Permissible Exposure Limit.
May be a Time Weighted Average (TWA limit) or a "ceiling" concentration exposure
limit. |
| pH |
Numerical logarithmic scale
from 0 to 14 indicating whether a product is acid (pH < 7), alkaline (pH > 7) or
neutral (pH = 7) |
| 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 oxidising agent, pyrophoric, unstable
(reactive) or water-reactive substance. |
| PMCC |
Pensky Martens
Closed Cup : a flash point test method. |
| Polymer |
A high molecular weight
material formed by chemically joining together five or more molecules (monomers). |
| Polymerisation |
A chemical reaction in
which a large number of relatively simple molecules combine to form a large chainlike
molecule. A hazardous polymerisation is a reaction which takes place at a rate which
releases large amounts of energy. |
| Polynuclear Aromatic
Hydrocarbons |
Organic compounds usually
composed of three or more aromatic rings. Some of these compounds (esp. 4-6 ring
compounds) are capable of causing skin tumour formation. Also known as PNA's or PAH's. |
| Pour point |
The lowest temperature at
which a liquid will flow or pour. |
| ppm |
Parts per million; a unit
for measuring the concentration of a gas or vapour in air,' parts (by volume) of the gas
or vapour in a million parts of air. Concentration of a particular substance in a liquid
or solid. |
| ppb |
Parts per billion : a unit
for measuring the concentration of a gas or vapour in air; parts (by volume) of the gas or
vapour in a billion parts of air. Also used to indicate the concentration of a particular
substance in a solution or solid. |
| Preparation |
Intentional mixture or
solution composed of two or more substances. |
| Protective Clothing |
Clothing designed to
provide protection to the wearer against contamination from chemical, biological,
radiation or physical hazards. |
| psi |
Pounds per square inch.
Unit of pressure.
Normal atmospheric pressure = 14.7 psi |
| Pulmonary Oedema |
The abnormal accumulation
of fluid in the tissue and air spaces of the lungs. |
| Pyrolysis |
The breaking apart of
complex molecules into simpler units by the use of heat, as in the pyrolysis of heavy oil
into gasoline. |
| Pyrophoric |
A chemical that will ignite
spontaneously in air. |
| Radioactive |
The property of an isotope
or element which is characterised by giving off radiant energy in particles or rays by the
disintegration of atomic nuclei. |
| Reactivity |
The tendency of a substance
to undergo a chemical change with the release of energy. Undesirable effects (pressure
build-up, temperature increase, formation of noxious, toxic or corrosive by-products) may
occur because of a reaction to heating, burning, direct contact with other materials or
other conditions when in use or in storage. |
| Reducing Agent |
The material which is
oxidised or which allows easy oxidation. |
| Respiratory Protection |
Devices for use in
conditions exceeding the exposure levels, which when properly selected, maintained, and
operated by the user, will protect the user's respiratory system from exposure to airborne
contaminants by inhalation. |
| Respiratory System |
The breathing system;
includes the lungs and the air passages (trachea or windpipe, larynx, mouth and nose) to
the air supply outside the body. |
| RID |
European regulations for
rail transport of hazardous goods. |
| R phrases |
Risk phrases : a set of
numbered standard sentences which appear on user labels for packaged goods (e.g. R23 :
Toxic by inhalation). |
| Second Degree Burn |
A burn that is more severe
than a first degree bum, and is often characterized by blistering, reddening of the skin,
oedema and destruction of the superficial tissue. |
| Sensitiser |
A substance, which on first
exposure, causes little or no reaction in man or test animals, but which on subsequent
exposure(s) may cause a marked allergic response, not necessarily limited to the contact
site. Skin sensitisation is the most common form in the industrial setting, although
respiratory sensitisation to a few chemicals has been known to occur. |
| SETA |
Setaflash Closed Tester; a
flash point test method. |
| Simple Asphyxiant |
A substance which induces a
deficiency in the supply of oxygen. Nitrogen, methane and acetylene are examples. |
| Skin Lesion |
An abnormal change in the
structure of the skin due to injury or disease. |
| Solubility in Water |
The percentage of a
material (by weight) that will dissolve in water at a specified temperature.
negligible or nil
|
less than 0.1 percent |
slight
|
0.1 to 1.0 percent |
moderate
|
1 to 10 percent |
appreciable
|
more than 10 percent |
complete
|
soluble in all proportions |
|
| Solution |
Uniformly dispersed
mixture. All solutions are composed of a solvent (water or other fluid) and the dissolved
substance, called the "solute". |
| Specific Gravity |
The ratio of the weight of
material to be weight of an equal volume of water usually at 20 degrees C, unless
otherwise specified. Specific gravity of water = 1. |
| S phrases |
Safety phrases : a set of
numbered standard sentences which appear on user labels for packaged goods (e.g. S 15:
Keep away from heat) |
| STEL |
Short Term Exposure Limit
(see TLV-STEL). |
| Substance (chemical) |
Chemical element and its
compound in the natural state or obtained by any production process, including any
additive necessary to preserve the stability of the product and any impurity deriving from
the process used, but excluding any solvent which may be separated without affecting the
stability of the substance or changing its composition. |
| Symbol |
Pictogram appearing on user
labels for packaged goods, also characterised by a letter (e.g. picture of flame and F+ :
very flammable substance). |
| Symptom |
Abnormality in the body
which is noticeable only to the person experiencing it and may indicate poisoning or
disease. |
| Systemic Toxicity |
The adverse effects caused
by a substance, affecting the body in a general rather than a local manner. |
| TCC |
Tag (Tagliabue) Closed Cup
: a flash point test method. |
| Teratogen |
A substance that upon
exposure to the parent causes malformations and/or alterations in the appearance or
function of the foetus. |
| Third Degree Burn |
The most serious type of
bum, is characterized by charring (blackening) of the skin, and skin necrosis (tissue
death). |
| TLV |
Threshold Limit Value : a
term used to express the airborne concentration of a material to which nearly all persons
can be exposed day after day, without adverse effects.
| TLV-C |
Ceiling Exposure Limit, the
concentration that should not be exceeded, even momentarily. |
| TLV-STEL |
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 that the
daily TLV-TWA is not exceeded). |
| TLV-Skin |
(Listed substance followed
by the designation "skin"): The skin designation refers to the potential
contribution to the overall exposure by the cutaneous route, including mucous membranes
and the eye. Exposure can be either by airborne or direct contact with the substance. This
"attention calling" designation suggests appropriate measures be taken to
prevent skin absorption. The TLV is not invalidated. |
| TLV-TWA |
The allowable Time Weighted
Average concentration for a normal eight hour workday or 40 hour work week. May also be
adjusted for extended work shifts. |
|
| TOC |
Tag (Tagliabue) Open Cup :
a flash point test method. |
| Toxicity |
Inherent capacity to
produce injury. Adverse effects resulting from overexposure to a material, generally via
the mouth, skin, eyes or respiratory tract. |
| Toxicology |
The study of the key
effects of chemicals and or physical agents on living systems, including evaluation of
safety. |
| Transient |
Short in duration. |
| Transport Emergency Card
(Tremcard) |
Instructions on how to deal
with emergencies involving hazardous chemicals, transported by road. |
| Tumour |
Abnormal mass of tissue. |
| TWA |
Time Weighted Average
exposure: the airborne concentration of a material to which a person is exposed, averaged
over the total exposure time, generally the total workaday, (eight to twelve hours). Also
see "TLV". |
| Ulcer |
A lesion (wound/injury) on
the surface of the skin or mucous surface. |
| Unconscious |
Not conscious : incapable
of responding to sensory stimuli. |
| Unstable |
Tending toward
decomposition or other unwanted chemical change during normal handling or storage. |
| Unstable (Reactive) |
A chemical which in the
pure state, or as produced or transported, will vigorously polymerise, decompose,
condense, or will become self-reactive under conditions or shocks, pressure or
temperature. |
| UN Number |
United Nations Substance
Identification Number (for transport purposes). |
| Upper Flammable Limit
(UFL) |
The highest concentration
of a flammable vapour or gas in air (usually expressed in percent by volume) above which
propagation of a flame will not occur in the presence of an ignition source. Also called
upper explosive limit or UEL. |
| Upwind |
In the direction from which
the wind is blowing. Also see "downwind". |
| Vapour Density |
The relative weight of a
vapour compared to an equal volume of air (indicates whether vapours will rise or sink). |
| Vapour Pressure |
Pressure of saturated
vapour above liquids or solids (usually provided at 20°C). The higher the vapour
pressure, the higher the concentration will be in unventilated spaces. |
| Viscous |
Having resistance to flow. |
| Water-reactive |
A chemical that reacts with
water to release a gas that is either flammable or presents a health hazard. |
