Western Australian Consolidated Regulations Western Australian Consolidated Regulations The State mining
engineer may, in writing, exempt a mine from all or part of this Division
where the sum of the effective doses from external radiation and intake of
radioactive dust is below 1 millisieverts (0.001 Sv) per year for each
employee and the long term average concentration of radon in the workplace is
below 1 000 becquerels per cubic metre, but only if the exposure to radon
is due solely to adventitious exposure to natural sources of radiation.
[Regulation 16.3 amended in Gazette
13 Nov 1998 p. 6221.]