TWAC Protectant, Installation Manual

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TWAC Installation Manual Ver: 0118 CodeMark™ CMA-CM40036
9. Regard all substances as hazardous, unless there is definite information to the contrary.
10. Clean up spills immediately and thoroughly in the prescribed manner.
11. Never store flammable or other dangerous goods near exits.
12. Always keep quantities of dangerous goods to a minimum.
13. When chemicals of any kind are in use, appropriate protective clothing must be worn.
14. Eye protection must be used at all times when using chemical materials.
3.0 How Chemicals Harm Us
Chemicals may cause injuries in several ways:

By force – such as an explosion, when flammable vapours are ignited.

By poisoning – .by ingestion, inhalation, skin absorption or via the eye

By destruction of tissue – such as an acid burn.

By displacing the air – e.g. carbon monoxide from combustion or an LPG leak from a
cylinder.
3.1 Personal Exposure to Chemicals
Before discussing the chemical materials you will be handling it is important to understand some of
the terminology that you will come across in your primary references on safety, the Material Safety
Data Sheet and the product labels. One of the first concepts that we need to become aware of is
exposure .
It is this concept that demonstrates that the same chemical can be both harmful and harmless. There
are three aspects of exposure that we must be familiar with:
a) Dose (how much) - a millilitre or a litre. Basically, the amount of substance administered or
you are exposed to.
b) Duration and frequency (how long and how often) - a minute or two or an hour, once or
every day for a year.
c) Route (how the victim is exposed) - drinking it, spilling it on the skin, or breathing its
vapours.
Changing any one of the aspects may change the effect. For example, water is harmless under the
following conditions:
1. Dose - 20 litres.
2. Duration - 5 hours.
3. Route - poured slowly over the head.
However, if we change the exposure conditions it can alter the consequences:
1. Dose - 20 litres.
2. Duration - 5 hours.
3. Route - head held under water in a bucket.
Although this may seem like a silly example, it highlights the principle that changing one aspect of
exposure can alter the effect.
As a generalisation, increase the dose, decrease the time it takes for the nominated hazard to occur.
Also, as dose increases, generally so does the severity of the injury. Keep in mind that a small dose
may not lead to immediate injury, but longer-term problems may arise.
Another term that is important to dosage is threshold . Threshold is the dose at which a chemical
begins to be harmful.