Silica dust in the workplace - Information for business owners and managers
A significant number of people die from occupational respirable dust diseases in Australia every year.
Building products such as kitchen stone bench tops, concretes, and quarry products contain a mineral known as crystalline silica. When workers cut, grind and drill these products under dry conditions, tiny particles of respirable crystalline silica (RCS) dust can be released into the air. Exposure to RCS dust has been linked to various occupational diseases including silicosis and lung cancer.
RCS is a known carcinogen and is listed as a hazardous chemical under the Northern Territory’s work health and safety laws (the Work Health and Safety (National Uniform Legislation) Act 2011 and Regulations).
See the NT WorkSafe bulletin Risks associated with Respirable Crystalline Silica for more information.
Person Conducting Business or Undertaking’s Duties
Under the Northern Territory’s work health and safety laws a Person Conducting Business or Undertaking (PCBU) must identify hazards and assess the risks that are posed to workers at the workplace.
The PCBU is required to eliminate such risks using risk control measures such as the use of alternative products that do not contain silica. If this is not possible, the PCBU must manage the risks through a hierarchy of risk control measures.
The PCBU is required to provide workers with appropriate information, training, instruction and supervision on the relevant RCS dust control measures. This should include the provision of relevant information on the use and care of personal protective equipment (PPE) and on personal cleanliness.
In addition, as RCS is a hazardous chemical the PCBU may need to undertake air monitoring at the workplace and health monitoring of workers that may be exposed to RCS. These requirements are set out below.
A checklist has been developed to help PCBUs assess the risks of RCS and the controls to manage those risks at their workplace. It can be downloaded from the NT WorkSafe website.
RCS workplace exposure air monitoring
A PCBU is required to assess the workplace to determine if a workplace exposure air monitoring is required. When making this assessment remember that the type of activity being undertaken and the working environment affect the likelihood of dust release. When high levels of dust release are combined with using materials high in RCS, then the resulting risk to workers is high.
If required, air monitoring must be performed to determine if the workers’ exposure levels are within acceptable levels. It must be remembered that air monitoring does not replace the need for the establishment of effective control measures.
The Northern Territory’s work health and safety laws establish a maximum airborne concentration standard for exposure to dusts containing RCS where the exposure cannot be prevented. In this case, the relevant exposure standard is the 8 hour Time Weighted Average Exposure Standard (TWA-ES) of 0.1 mg/m3 measured as RCS in the respirable dust portion of a dust cloud.
RCS health monitoring
The Northern Territory’s work health and safety laws require a PCBU to ensure that health monitoring is provided to a worker if that worker is carrying out ongoing work using, handling, generating or storing hazardous chemicals and there is a significant risk to the worker’s health because of exposure to a scheduled chemical (including RCS).
Health monitoring means observation and checking of a person to identify changes to their health status because of exposure to hazardous chemicals. It is the responsibility of the employer to cover the costs of any consultations with the GP or specialists if required and any costs of medical tests related to the health monitoring. If you send a worker to a GP (or ask them to attend their GP at your expense) be aware that in almost all cases, the worker will be immediately referred to either the Royal Darwin Hospital or Alice Springs Hospital.
There are private specialists providing occupational health monitoring in the Northern Territory and it may be worthwhile discussing a health monitoring scheme with one. You can find one through the Royal Australasian College of Physicians.
See the Safe Work Australia guide Health monitoring when you work with hazardous chemicals guide for more detailed information.
Workers’ compensation
The Return to Work Act 1986 establishes the Northern Territory’s no fault workers’ compensation scheme. If a worker suffers an injury or disease in the course of employment, including a silica-related disease, they may be eligible to make a claim for entitlements such as:
- payment of medical and other reasonable expenses
- weekly payments of income maintenance while unable to work
- rehabilitation services
- assistance to return to work
The Return to Work Act 1986 requires employers to hold a current workers' compensation policy if they employ a worker.
See the NT WorkSafe bulletin Workers Compensation Insurance requirements for employers for more information.