CoSHH - Construction and Silica

Many products used in the construction industry contain silica such as stone, brick, tiles and concrete.

Silica itself is not hazardous but silica dust, otherwise known as Respirable Crystalline Silica (RCS), can cause a number of health problems for workers who are exposed to it. The term 'respirable' means that dust particles are so small that they can easily be ingested into the lungs.

Activities which can result in high exposure to silica dust include stone masonry, concrete cutting and tunnelling. The Health and Safety Executive (HSE) estimate that around 140,000 British construction workers are regularly exposed to silica dust.

Inhaling RCS can cause lung damage (silicosis) and it is in fact the world's oldest known occupational disease. Silicosis can result in the lungs being scarred and thus will lead to breathing problems. In acute cases it causes irreversible damage to the lungs and can cause permanent disablement and premature death. Heavy and long periods of exposure to silica can also lead to lung cancer.

It is essential that employers find out how much silica their employees are exposed to. There is a maximum exposure limit (MEL) of 0.1 mg/m3. Exposure to RCS should be reduced so far as is practical, and should be always below the MEL.

If workers are exposed to silica then their work activity should be subject to the Control of Substances Hazardous to Health Regulations 2002 (CoSHH). CoSHH guidelines stipulate that risks to workers health should be assessed and controls put in place.

Employers have a responsibility to minimize the risks that workers are exposed to. Essentially, they should try and get rid of silica dust in the workplace. This is possible by sometimes substituting silica for other materials such as using non-silica grits for blasting.

If an alternative product is not available and you cannot get rid of silica dust, then exposure should be controlled. This is possible using dust suppression techniques or local exhaust ventilation (LEV). A better alternative to trying to control exposure by ventilating a whole area is to remove the dust at source which is where LEV equipment is beneficial.

Personal protective equipment (PPE) may help in certain circumstances but they need to be backed up with respiratory protective equipment (RPE) as well. Workers should be well trained in the use of PPE and RPE. They should be monitored and supervised and equipment maintenance is crucial.

Good washing facilities should be made available to workers as well as suitable storage areas for contaminated work clothing.

Once the right controls are in place it is important that they are all working properly. Checks should be made on a regular basis alongside staff training.