The Setting
The setting takes place on United States Scientific Ourpost North 31 located in the middle of the god forsaken climate of Antartitca from what I have seen of the movie the scientific outpost includes the following but is not limited to:

1.A tool Shed
2.The Entertainment room (poker,cards ect.)
3.The Dog Kennel
4.Childs/Palmers bedroom
5.The station hospital
6.Mac Readys Shack
7.Fuchs Office
8.The generater room
I may have missed a few
and I THINK certian team members might have their own private rooms...

The Blair Files
When Blair went bonkers and tore up the snowmobile and helicopter I don't thing he was infected mabye a little off (but who wouldn't be in that situation)but was just trying to prevent ''THE THING'' from reaching the coastline -Note: The U.S. base is about 1000 miles away from the coast based on what Blair said when he was tearing up that room...

1.But that spaceship he was building must of taken alot of time to build and they said that he must of used parts from the helicopter and snow mobile to build it...

2.Why would Blair if he was infected earlier tearing the room apart take the risk that he might get killed before he got to put the spaceship together. He would had to put together that plan long before it happened.

FINAL ANALASIS: Blair became infected either before he went nuts or after he was put in the tool shed...

Your infected just like the rest!