Anyone with anything to do with Health and Safety issues in their factory has probably come across this term, SILICOSIS. But what actually is silicosis, and should I be worried about it?
Silicosis is a disease of the lungs caused by prolonged inhalation of fine crystalline silica dust, also sometimes referred to as "free silica".
When workers inhale crystalline silica, the lung tissue reacts by developing fibrotic nodules and scarring around the trapped silica particles. This fibrotic condition of the lung is called silicosis. If the nodules grow too large, breathing becomes difficult and death may result. Silicosis victims are also at high risk of developing tuberculosis.
So silicosis is a very nasty disease that one would prefer to avoid. The scariest bit is the law suits that companies can face from workers who get silicosis in the workplace. A class action law suit by mining workers against South African mining company Anglo American has succeeded and led to a R500m compensation payout to the workers (read more here).
Generally the types of workers most at risk are those in the blasting, glass, foundry and mining industries where fine sand (or silica) is constantly in the air. So us filler users don't really need to worry about it then?
Not so simple, I am afraid. The questions we must ask ourselves are:
In our Abrasion article, we discussed fillers which have free silica left in them from the milling process. This silica can greatly increase the abrasiveness, even if the filler in its pure form is a very soft mineral (like talc). Well that free silica content has a second disadvantage – the danger of silicosis! Fillers are usually dusty white powders and unfortunately many factory workers hate to wear dust masks.
How will I know if there is free silica in my filler? The easiest way to find out is to ask your supplier this question. Another way is to send a sample away to have it analysed for crystalline silica content.
Once you know whether a filler contains any fine free silica dust, you can put the required safety measures in place. However since no fine dust is good for the lungs anyway, the safest approach is to insist on the use of dust masks whenever fine powders are handled.