How To Protect Against The Dust Particles That Cause Lung Disease

Silicosis is a real and present danger on many worksites. Colin Gibson, HSE manager at Master Electricians Australia, explains what this means to you.

Silica is a naturally occurring material found in quartz, rock and sand and, as such, is a key component of many building materials. Dusts generated from working with materials containing silica can penetrate deep into our lungs, causing cancers and death.

Lung disease in tradies through history

For centuries humans have been working with brick, stone and tiles, and for almost as long medical practitioners have noticed lung diseases and premature deaths among stone workers and associated trades.

In 1700, Italian Dr Bernardino Ramazzini noted evidence of disease in stone cutters, but the name silicosis wasn’t given to the condition until 1870.

The incidence of silicosis increased rapidly in the early 1900s with the advent of pneumatic hammer drills and sandblasting, and it is now becoming more common in the construction and related industries.

Respirable Crystalline Silica (RCS) is the name given to the minute dust particles that are capable of being inhaled to the deepest part of the lungs (1 to 10μm size) where they irritate the lung membranes and cause disease. As well as lung cancers, ssilicosis — an incurable condition — has also been linked to chronic bronchitis, emphysema, kidney disease and scleroderma.

Any operation involving concreting, drilling, cutting, grinding, hammering, polishing any rock/stone (manufactured or natural), concrete, ceramic and tile materials is highly likely to produce RCS dusts.

Symptoms of silicosis

Depending on a person’s exposure, symptoms can take decades to become apparent, but include shortness of breath, chest pain, fatigue and severe cough.

The Royal Australasian College of Physicians identifies three main types of exposure:

• Chronic – at least 10 years of exposure to RCS
• Accelerated – 5 to 10 years exposure,
• Acute – exposure less than 1 year

The Australian Cancer Council estimates that in 2011, 587,000 Australian workers were exposed to silica dust on work sites, and it expects about 5758 of those to develop lung cancer as a result.

Exposure standard

As of 01 July 2020, the Australian exposure standard for RCS was reduced to 0.05mg/m³ of air for an 8-hour time weighted shift, based on a five-day working week. If you piled this level of dust from an 8-hour shift together it would roughly cover half the area of a matchhead. When suspended in the air, this amount of dust is not visible, meaning hazardous levels of dust can be present without you knowing.

Controlling silica dust

Given the vast range of uses for silica containing materials and the environments they are found in, there is no simple one-size-fits-all control method. The below are suggestions for managing RCS dusts.

• Instead of drilling into concrete once it has set, consider if it’s possible to cast fasteners or mounts into concrete as it is poured.
• Use other materials for the same task. Some manufactured stone products contain over 90% silica, whereas some concrete materials contain 25% only.
• Whenever possible, use wet cutting or dust capture systems. Wet cutting prevents dust becoming airborne; however, waste material must be cleaned up and safely disposed of before it dries and gets blown or swept away.
• Dust capture systems can be very effective but must be properly maintained.
• Dust hoods can capture all dust produced, however if you are drilling close to corners or edges, some may struggle to capture everything.
• Vacuum systems must be carefully selected to ensure they filter to the exposure standard.
• Organise jobs so your workers are not on site when other trades (i.e. tilers) are. If this is not possible, try to organise to work elsewhere on site or ‘up-wind’ of other trades.
• Very few systems are totally effective at capturing hazardous dusts, therefore respiratory protection will still be required. P2 is the minimum level required. Training workers on how to use respirators and ensure an effective seal is vital. If workers are not clean shaven, you will need to investigate positive pressure respirators.
• Consideration needs to be given to dust settling on clothes and hair, which could be dislodged and inhaled after a respirator has been taken off.

More info on RCS

Contact Master Electricians Australia on 1300 889 198 or your professional association for information, guidance and support. Workplace Health & Safety Regulators in each state and territory also maintain resources to assist businesses manage silica dust, as does WorkSafe Australia.