De-icing operations

Right now there's a Red Line train heading toward Alewife with the rear control car closed off, lights out, and a big sign in the window saying "De-Icing Work Train".

Unfortunately I didn't get that car number, but the other end (the control end that's active going North) is 1718.
http://sites.harvard.edu/~wuensch/T/sub ... l?car=1718" onclick="window.open(this.href);return false;

I would love to know / see pictures of what's in that de-icing car, especially since it's enough equipment to require the car to be out of service.

Okay, this make total sense.

Coming down the stairs from the Green to the Blue at Government Center I saw my train was already in the station. As I was running to catch it, I saw that the first car was lights out with some large sign in the windows. The motorman only reference over the mic that the first car was out of service.

This must have been the same deal. Good to know.