The province is preparing new rules to make mining safer.
It includes improved ventilation requirements for underground mines and lower legal limits for diesel exhaust at a mine site.
Labour Minister Monte McNaughton says the new standard will be the toughest in North America.
"These new rules will save lives by lowering the amount of harmful chemicals from diesel exhaust allowed in underground mines. This is something that miners in their union have called for years, and we're listening," says McNaughton.
The United Steelworkers Union is welcoming the reduction.
It has been seeking lower limits since the government began a public discussion in 2018.
Nick Larshell, a local union president, says reducing the limit by 70 per cent is a good start, but it will still be higher than the level used on smog days.
"On a smog day, you're asked to stay inside when it's 50 parts per million. This current level from 400 to 120 is amazing. But think about that. You're asked to stay indoors at 50 and we're working at 120. So we're looking forward to the work that has to get done to bring that number down," says Larshell.
Along with the lower limits on diesel exhaust, the province says it will permit the use of track-mounted robots in underground mines.
These units can be operated remotely and, with a camera, can identify hazards like loose rocks and misfired explosives.
"Our mission is simple to keep our workers safe. The changes we're making will keep our minds some of the safest in the world," says McNaughton.
The regulatory amendments are to come into effect this July.
Others will come into play in September to allow employers time to comply.