The union covering some of Australia's deadliest workplaces has lashed the under-resourced NSW regulator for an "incredibly lazy and hands-off approach" to workplace safety.
The CFMEU called for a broom to be put through SafeWork NSW after a damning report uncovered failings including the response to emerging lung diseases caused by engineered stone dust.
Despite national data showing serious workplace injuries had been increasing, there had been a trend for complaints to be treated as less serious, the report by the NSW Auditor-General said.
CFMEU NSW state secretary Darren Greenfield on Thursday said the "shocking" report showed what the union had been arguing for a decade: the regulator was "taking an incredibly lazy and hands-off approach to workplace safety".
A UK firm named in the reports attacked SafeWork for undertaking an "unscientific and poorly designed test" of its dust-monitoring device.
The report outlined issues with the promotion of the Air XS real-time silica monitor despite concerns inside SafeWork about the efficacy of the $18,500 product.
It was only sent for further testing after the audit office raised the issues with the boss of the regulator.
But maker Trolex Group said it had already told SafeWork its original testing was meaningless.
"SafeWork’s concerns about the efficacy of our award-winning monitor were based on a highly unprofessional test carried out using an un-calibrated first-generation demonstration device, which did not even follow the device's manual," Glyn Pierce-Jones said in a statement.
The auditor-general, which referred concerns about the tendering for the device to NSW's corruption watchdog, had not contacted Trolex.
The company would happily cooperate with any corruption inquiry, Mr Pierce-Jones said.
SafeWork NSW is due to be overhauled following the audit and another independent review that called for it to be set up at arms-length from the government.
The regulator on Thursday conceded it was well short of international minimum standards for one inspector per 10,000 workers.
Another 73 inspectors - or 20 per cent of the current cavalry - were needed to meet that standard, Safework NSW head Trent Curtin told parliamentary budget estimates.
Work Health and Safety Minister Sophie Cotsis said she would like to see more inspectors, but funding requests needed to go through a budgetary process.
She suggested resources would also be realigned when the government acted on the recommendations from the two independent reports.