Thats a very good question. My guess is that its not compliant due to the newer regulations.
However, it did receive a lot of work during the 1990's, prior to its snow clearing adventures. However, I suspect it would need to have the boiler re-certified, but I am just guessing. Good question for the C&TS folks.
Greg Scholl
PS...I wonder if it falls under the same rules since it is not a passenger hauling machine, but used for maintenance.