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SAFETY AND HEALTH ALERTS AND GUIDANCE
KNOW YOUR HAZARDS: SPOTLIGHT ON SILICA The International Agency for Research on Cancer (IARC), part of the World Health Organisation (WHO) of the United Nations, has classified silica as a Class 1 carcinogen, causing lung cancer, renal disease and autoimmune diseases including rheumatoid arthritis. ...
WHAT IS SILICA DUST? Crystalline silica (quartz) is a naturally occurring mineral found in most rocks, stone, sand and clay, and in brick, concrete, tile and manufactured stone prooducts. When working with these materials, the silica is released as a fine dust. This dust is respirable crystalline silica (RCS), commonly called silica dust.
WHAT IS THE HAZARD?
The workplace exposure standard for RCS is exceeded when the amount of dust a worker breathes over a full shift contains more RCS than the amount shown here next to a five cent piece. However, workers may still suffer adverse health effects from lower levels of exposure.
Breathing in RCS can cause: •• •• •• •• •• ••
silicosis lung cancer (associated with silicosis) kidney disease increased risk of tuberculosis possible increased risk of autoimmune diseases chronic obstructive pulmonary disease (COPD).
WHICH WORK ACTIVITIES HAVE A HIGHER RISK OF EXPOSURE? Examples of work activities that can generate RCS include: •• fabrication and installation of composite (engineered or manufactured) stone countertops Note: Silicosis risks are much greater when working with engineered stone as it contains up to 95% crystalline silicia while natural stone contains 5-50% silica
WHAT IS SILICOSIS? Silicosis is an incurable lung disease, with inflammation and scarring of the lungs, causing shortness of breath, coughing, fatigue and other symptoms. There are three types of silicosis: •• acute silicosis results from short-term exposure to very high levels of silica over a period of weeks or months to several years •• accelerated silicosis results from 5-10 years’ exposure to high levels of silica – this is becoming more prevalent in workers who work with engineered stone •• chronic silicosis results from long term (more than 10 years) exposure to lower levels of silica.
ThinkSafe vol. 1 no. 1 January 2019 |
11 |
