It has been a long time since a key Australian industry has been under serious threat from industrial action but that is suddenly the case in the coal industry. The repercussions of a 1996 accident at the Gretley coal mine in the Hunter Valley, New South Wales, are still being felt, with a landmark court ruling fining the mine's new owner Xstrata under occupational health and safety laws. Xstrata bought the mine from its previous owners, who were fined A$1.46 million over the accident in which four miners drowned after drilling into a flooded shaft. While Xstrata has appealed the judgment, New South Wales coal miners have threatened an extended strike if the bid to overturn workplace safety laws is successful. Xstrata and miner Centennial Coal - fined over another incident in 1998 - are seeking to overturn laws that apportion responsibility to employers for workplace deaths. Last month, miners travelled to Sydney from regional New South Wales, with four empty coffins to symbolise their dead colleagues, and demonstrated outside the Industrial Relations Commission. Miners say they cannot be expected to work if employers are not held responsible for their safety. The case is a simmering time bomb for the coal industry. A decision is pending, but if it favours Xstrata producers might face more worries than poor infrastructure.