Union officials are being "denied entry" to take dust measurements in worksites, according to ACTU Assistant Secretary Liam O'Brien.
"This is really shocking that employees would be denying the rights of workers to have their representatives there to actually, independently validate dust levels," Mr O'Brien told Sky News Australia.
"We recognise that in some of these environments like tunnelling, like quarrying, like construction and building trades more broadly, that you can't eliminate risks like we can with engineered stone.
"The reality is, clearly we need stronger laws here."