check with the local utility. usually they can tell you based on their specs. if you obtain a specs and installations guide you will have your question answered, that is if it belongs to a utility.
As far as the oil-filled. i agree with caj1962. check section 450. it will give you all the details.
Originally posted by ddepuy: IS THERE A NEC REQUIRED DISTANCE FROM A BUILDING THAT AN OIL FILLED TRANSFORMER MUST BE?
You need to refer to the NESC and fire codes for transformer spacing requirements - & yes there are specific requirements. Use of non-flammable or high-flash point oils, such as R-Temp, can reduce some of these requirements.