Farmers and miners in Western Australia are alarmed by new national workplace exposure limits that take effect on 1 December, cutting the accepted exposure level for hundreds of dusts, fumes and chemicals — including the grain fumigant phosphine and grain dust itself. Industry groups say some of the new limits are so low there is no practical way to measure them, and are asking governments to change or delay the rollout.

West Australian Grain Group chair Alastair Falconer said the exposure limit for phosphine will fall by 80 per cent, which "almost renders phosphine unusable". Most grain storage in Australia depends on phosphine to keep insects out of stored and exported grain, and many importing countries reject a whole shipment if insects are found. Exports underpin Australia's $33 billion grain industry.

The limits for grain dust, including oats, wheat and barley, have been more than halved. Mr Falconer said the industry was scrambling to work out how to measure and comply. "When we're blowing down harvesters, we're cleaning out our own silos, what exposure is that giving us, how do you measure exposure when you're blowing down a harvester, and what's the correct PPE to use?" he said, calling for a three-year delay while the levels are researched.

Safe Work Australia said the revised limits reflect current scientific evidence and independent expert advice, were consulted on in 2019–21, agreed by work health and safety ministers and published in April 2024 for implementation on 1 December 2026. It acknowledged questions over how the phosphine and other limits apply in practice and said it is working with industry, the Australian Pesticides and Veterinary Medicines Authority and the Department of Agriculture, Fisheries and Forestry. Compliance, it said, is assessed by personal air monitoring of workers rather than at fixed points.

The standards are set nationally but enforced by each state. WorkSafe Victoria said in August it would delay the limits for 15 airborne contaminants, including phosphine, until 1 December 2029. Grain groups met Western Australian Agriculture Minister Jackie Jarvis last week; she told the ABC she was seeking more information on the impact of the phosphine limits. More than 600 substances are covered by the new system, with limits tightened for about 250.

Mining groups have made the same request. Association of Mining and Exploration Companies chief executive Warren Pearce said the "blanket" approach was not always practical — manganese being one case where the industry cannot show it can measure below the new limit — while stressing that worker safety, after asbestos and silica, must come first. Minerals Council of Australia chief executive Tania Constable said the changes had significant implications across many industries and that consultation was under way. Joanna Prendergast reported for ABC Rural.

Source: ABC Rural