Just a note on the weather.
When i worked up North we were unionized. The collective agreement specified that when the wind chill hit 2500 it was time to shut down. This is a combination of temperature and air movement. 30 below with no wind is not so bad where conversely 20 below with a wind of any strength will significantly increase the temp and man's ability to with stand. The clothing is very good today. High tech materials eliminates heavy wool and allows for more movement from the worker. Less weight and less restraining.
The problem as another poster mentioned is the equipment. Breakdowns occur more often and its a little slower to repair but the human species is one tenacious animal. I have personally been involved in construction etc and got a lot of work done in the cold..
I don't know why this is typing in red. is this my computer or agoracom?.....Don