TWAC Protectant, Installation Manual

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TWAC Installation Manual Ver: 0118 CodeMark™ CMA-CM40036
How long, or the duration, a person is exposed to a chemical, affects how severe the injury will be.
For example, the severity of an injury caused by skin absorption will be decreased if the chemical is
washed off quickly. Or if you were to get battery acid on your hand, the quicker that you wash it
off, the less burning sensation and related acid burn you will receive.
How often, or the frequency, one is exposed to a chemical can affect the:

type,

time of onset,

extent, and

severity
of the nominated associated hazard.
Some chemicals cause immediate injury after only one exposure ( Acute Toxicity ); whilst others
cause injury after long-term exposure ( Chronic Toxicity ). This is due to the fact that the body can
excrete certain chemicals. The time required to eliminate chemicals from the body differs wildly.
Some chemicals may be cleared faster than they can be absorbed whilst others accumulate in organs
with time. Hence, one exposure to large quantities of a chemical may not result in any effect on the
person, whilst repeated exposure to small amounts of other chemicals may cause injury through a
build up, or some other effect, of this chemical in the body.
For example, many people may wash their hands in a solvent such as mineral turpentine or petrol to
get off grease and grim. Usually if you wash your hands in solvents like these for a minute or so,
you do not expect to see any issue with your hands. However, if you were to continuously wash
your hands in these materials two or three times a day over a number of months you would
eventually expect these solvents to have an effect on your hands due to the materials ability to take
the natural oils from your skin. What may happen is that you end up with drying and cracking of
the skin on your hands. In severe cases you may even end up with a case of chemical dermatitis.
3.2 Pathways into the Body
Chemicals can follow different pathways into the body. This is also known as Systemic
Exposure . Systemic exposure occurs in four ways; i.e. by Ingestion (Swallowed), Inhalation,
Absorption or through the Eyes.
3.2.1 Ingestion (Swallowed)
INGESTION is the most obvious route, but it is usually accidental. A person will have a chemical
on their finger that would then be placed in the mouth or onto food.
3.2.2 Inhalation
INHALATION or breathing in of chemicals is also obvious. Dusts, mists, gases, vapours and
sprays can all enter the lungs via the nose and mouth during normal breathing. This route provides
the most rapid entry into the body and hence the quickest onset of effect.
3.2.3 Absorption
ABSORPTION of chemicals through the skin is another way of chemicals entering the body.
Sometimes people are not aware of chemicals being absorbed through the skin. As a precaution,
gloves should always be worn when handling chemical materials.
Usually, skin absorption is a slow process through intact skin. However, cuts and abrasions
increase the rate of absorption. Skin absorption may also occur when clothing or shoes are
chemically contaminated, hence the requirement to clean dirty clothing.
3.2.4 Eyes
A less obvious route of chemical entry is via the EYE. Chemicals are rapidly absorbed through the
eye into the bloodstream. Chemicals can enter the eye as liquids or powders, by splashing or by