The FAA have just issued a safety alert for operators (SAFO) about hot refueling/loading following this accident:
Background: On May 30, 2009, a Bell 47G-2 helicopter operating under part 137 was being refueled with the engine running (hot fueling) when the ground crew spilled fuel onto the engine while trying to untangle a kink in the hose. The helicopter quickly caught fire and the pilot sustained serious injuries as a result.
The document can be found here:
http://www.faa.gov/other_visit/aviat.../SAFO10020.pdf
It appears to mirror European policy (JAR-OPS and EASA OPS) on hot fuelling with volatile fuel; as this is addressed in ICAO Annex 6, it is somewhat surprising that the FAA have only just felt compelled to issue a safety notice (not exactly proactive).
The reference (in the document) to FAR 91.9 is bizarre; it appears to limit hot refuelling only when there is a limitation in the Flight Manual. How many Flight Manuals have you ever seen that contain such a limitation. Once again, this is the FAA attempting to regulate operations from within a certification code!
Jim