This applies to employers in the foundry, ceramics, brick manufacture, heavy clay, quarry, industrial minerals, construction and stonemasonry industries, and any other producer or user of silica flour whose employees could be exposed to respirable crystalline silica dust.

From 1 October 2006, a revised workplace exposure limit (WEL) for respirable crystalline silica (RCS) will reduce the existing limit.

The new WEL value for RCS will be 0.1 milligrams of RCS per cubic metre of air averaged over an eight-hour period (expressed as 0.1 mg.m-3).

If the new limit is exceeded the HSE recommend the following:

• Respiratory questionnaire
• Spirometry
• Chest X-ray every 5 years for 20 years of working life & then every 3 years.
• Observe sickness trends of chest illnesses over 12 month periods.