The explosion occurred during a propane transfer from a Doxol railroad car to a storage tank on the Getz rail siding near Andy Devine Avenue/Route 66.
The incident began when a hairline crack in the side of the tanker was leaking non-odorized gas that was ignited by static electricity.
This caused a spark that ignited the leaking propane gas, facts identified after a long investigation and trial had been conducted.
[1] The fire department was in the process of setting up a deluge gun to cool the car, which would have delivered far more water than the booster attack lines they initially were using.
Almost instantaneously, thousands of gallons of boiling liquid propane flashed to gas with the drop in pressure and simultaneously ignited.
Burning propane rained down on everything in the vicinity, and the remnants of the rail car were propelled over a quarter mile from the explosion site.