We attended a live fire training exercise at our county fire training grounds. The grounds are well maintained and watched over by numerous full time training professionals. Areas depts are permitted to use the grounds under the supervision of the training staff. This particular training ground has a 2 story concrete building that support both Class A burns and propane burns. While training on the second floor (a propane room) the room filled with unburned propane vapors. With two fortunately well trained FF working an evolution the excess gas lit off causing a propane flashover. Injuries were limited to minor burns around the hood, and on the ears.
LESSONS LEARNED: There is some talk that this prop has been "acting up recently" if that is the case the prop should not be used until it’s correct operation is verified. Make sure everyone knows that even in the "same old burn building" that you have been in many times before, you can get hurt.