Review of the workplace exposure standards

Safe Work Australia is reviewing the workplace exposure standards (WES) for airborne contaminants to ensure they are based on the highest quality, contemporary evidence and supported by a rigorous scientific approach.  

The limits to which workers can be exposed to hazardous airborne chemicals are published in the Workplace exposure standards for airborne contaminants (WES list)

The values published in this list are the airborne concentrations of a chemical that are not expected to cause adverse effects on the health of an exposed worker. 

WES values are generally based on the adverse effect that occurs at the lowest airborne concentration of the chemical, or the ‘critical effect’. 

There are three WES parameters under the model WHS laws: 

  • if the critical effect is a chronic or sub-chronic effect: 

  • eight-hour time-weighted average (TWA), and 

  • if the critical effect is a short term or acute effect: 

  • short term exposure limit (STEL), or 

  • peak limitation. 

The aim of this review is to develop a list of health-based recommendations for WES in Australia. Recommendations are made using a methodology and are informed by an evaluation of available information. 

Individual evaluation reports for each chemical were published in ‘releases’ on our consultation platform Engage feedback. Public feedback has now closed.   

All recommendations for WES resulting from this review will be considered by Safe Work Australia Members, along with the feedback provided by stakeholders.  Safe Work Australia Members will then make recommendations to Work Health and Safety Ministers as the relevant decision makers.  

Changes to the WES only become mandatory once adopted in the WHS laws in the Commonwealth, states and territories. There will be a standard three year transitional period for duty holders to comply with any amendments. 

WES review methodology

The following documents describe the methodology for reviewing the workplace exposure standards:

Supporting information