Silica dust and masonry cutting activities: What are the risks and how can they be controlled? Silica dust (crystalline silica) is a very common and naturally occurring mineral found in concrete, brick, and stone. It is released into the air during cutting, drilling, grinding, and polishing of these materials. Tiny respirable particles can then be inhaled into the lungs where they can cause a number of serious diseases. These include silicosis, lung cancer and autoimmune conditions, amongst others. These are serious and potentially life–limiting diseases. Silicosis, in particular, has featured heavily in the media recently, both in Australia and overseas. Silicosis is a progressive and potentially fatal lung condition but is entirely preventable when the right controls are put in place. Many construction-related tasks have been shown to release respirable silica dust into the air, including concrete cutting, grinding drilling, jack hammering and wall chasing of brick. Wall chasing is particularly common in the residential building industry in Western Australia. A Curtin University study has predicted that up to 103,000 Australians will be diagnosed with silicosis and more than 10,000 will develop lung cancer as a result of their current exposure to occupational silica dust. These numbers are shocking, but the good news is that silicosis and other diseases caused by silica dust exposure are preventable with the right control methods. So, what do the regulations say and what can builders and contractors do to manage the very real risk of silica dust on their worksites? In basic terms, hazards must be identified, risks assessed and practical controls to protect workers must be implemented. In Australia, the workplace exposure standard for respirable crystalline silica is 0.05mg/m3 over an eight- hour time weighted average. This is a tiny amount and reflects just how dangerous silica dust is. Workers are not allowed to be exposed to amounts any higher than this and employers and those responsible for worksites must ensure this is the case. Air monitoring is the only accurate way to properly assess the risk posed by respirable silica dust. Once this risk is quantified, then the hazard must be eliminated or substituted. If this is not practical, then engineering or administrative controls need to be used to reduce the risk. PPE can only be used to manage any remaining risk once these other, higher order, measures have been considered and implemented. If there is regular exposure over 50 per cent of the exposure standard, then health surveillance must be provided to workers. Wall chasing of brick for the installation of electrical cable or plumbing pipes is a very common construction activity in Western Australia. Using this activity as an example, it would usually not be possible to eliminate or substitute the brick as this material is an extremely common and accepted construction material. The next best control method available would involve using engineering controls. These controls help to remove dust at the source so less is released into the air. During wall chasing, the application of water and vacuum technologies on the saw has been shown to reduce airborne levels of silica dust, but some engineering controls are more effective than others. The WorkSafe Western Australia Silica Compliance Project Report monitored six workers on five sites during wall chasing activities and concluded that engineering controls utilising local exhaust ventilation (vacuum) and wet cutting in combination provided the most effective control for reducing dust exposures to saw operators and others nearby. So, the benefits of choosing best practice engineering controls to manage silica dust risk are clear in terms of potentially reducing workers’ harmful dust exposure, but there are tangible additional benefits to builders and contractors. Reducing overall business compliance risk and exposure to legal consequences is a significant consideration along with simplifying business practices and required compliance measures and reducing insurance costs. Controlling silica dust during wall chasing activities, and during masonry cutting in general, need not be onerous and can be simplified by ensuring best practice controls, which remove harmful dust before it is breathed in, are consistently applied. Builders and contractors have a clear responsibility to keep people safe. Silica dust is a widely known and significant health hazard, but with careful planning and the application of best practice at all levels, the risks of this deadly dust can be greatly reduced. to find out more: www.guardasystems.com 24 MASTER BUILDER WINTER 2023 ADVERTORIAL MB WA Journal Winter 2023_text 01.indd 24 MB WA Journal Winter 2023_text 01.indd 24 15/6/2023 3:53 pm 15/6/2023 3:53 pm