Chisel,hopefully the difficult boss will move on.In my field turnover is pretty rapid,best Ive found is salute,do whatever stupid thing they say,and stay out of their face.Stay OFF the difficult bosses radar,he can fire you.

Do a quick rant OFFSITE without any possible coworker being aware,and let it go.They cant torture or pollute your mind once off the clock,only you can do that,so dont.Let it go.I know,easier said than done,in that case mix a drink.

Some bosses are downright psychotic,I had one a while back,I was the only one attacked who came out ahead and the boss was canned,if it gets confrontational you had better be massively in the right or you are gone.And as Unimog said,it WAS a serious safety/legal issue and the bigger bosses couldnt ignore it,my boss had to go when the truth started coming out.

Many problems can be fixed by just outlasting it.Now the entire management team is gone (Fired) a year and a half later except the one at HR who backed me 100%,go figure.

Ive also voted with my feet and just moved on when the situation was that bad,but in this economy that can be a very hard thing to do I realize.

I sincerely hope your problem will have a suitable resolution.