Welding Fume in the Western Australian Mining Industry: Impact of a Change to the Workplace Exposure Standard

Abstract

The aim of this study was to analyse the Western Australian (WA) Safety Regulatory System (SRS) database to assess compliance of the WA mining sector regarding workers exposure to welding fumes and to identify trends over time. De-identified data analysed to assess the impact of reducing workplace exposure standards (WES) for general welding fumes on industry compliance. Historical trend analysis shows a shift from 100% compliance to 100% non-compliance, based on mean values and 95% confidence intervals, with exposure levels remaining consistent over time. These findings highlight the need for current, innovative engineering solutions, and raise questions about the validity of current sampling methods. Powered air-purifying respirators (PAPRs) integrated with welding helmets can reduce exposures by up to 99.96%, making their adoption as industry best practice critical, yet current sampling methodologies measure welding fume levels outside PAPRs, thus potentially misclassifying workers who are adequately protected as non-compliant. The sampling method is also influenced by other particulate matter present in the workplace that may be due to grinding or other dust generating activities in the vicinity of the welder. Lower WES values necessitate a review of exposure assessment and reporting methods to accurately reflect worker exposures.

Keywords: exposure assessment; sampling; welding fume.

Figure 1

Mean Welding Fume Results, including LCL and UCL (1986 to 2024). Note: The red line represents the repealed WES and the blue line the current WES (2024).

Figure 2

Mean welding fume results by commodity (2012 to 2024). Note only commodity types with 100 or more samples over the period have been included. Note: The red line represents the repealed WES and the blue line the current WES (2024).