Intoxication while operating heavy equipment is a safety hazard; if your employer is tolerating it, you can generally refuse to work where that hazard exists (by which I mean in injury's reach of that equipment while an intoxicated worker is operating it, not "refuse to work at all,"), and you can make a report to your province's occupational health and safety regulator. Both acts are protected by provincial employment law in every province; if you are fired for those reasons, you have recourse.

You will, however, need to notify your employer when you are refusing unsafe work, and why, and it's a good idea for several reasons to let them know about safety hazards before they get to that point. Fear of confrontation is reasonable enough, but the more you keep quiet about this, the weaker your protections are.