Ste-Elisabeth-De-Warwick, Que 27 June, 1993 Barn catches fire. 14 firefighters had just arrived at farm. 4,000 Litre propane tank BLEVEs. 3 killed when BLEVE fragment hits truck. 1 killed by BLEVE shock wave. 8 other people were injured.

News Release

Flammable Hazard V1.2 Bleve shock wave –2 lbs TNT - 5 psig PSO at 17 ft. Bleve Thermal Analysis –LC50 at 66 meters –Second Degree Burns at 126 meters Bleve Fragments –Disc fragments meters –Cube fragments meters –Sphere fragments meters

VCE - Early Ignition Total Instantaneous loss of propane. If congested area with vertical confinement. 12% blast efficiency by Clancey method tons TNT LC50 at 5 psig PSO at 59 meters LC10 at 1 psig PSO at 177 meters

VCE - Delayed Ignition Total Instantaneous loss of propane Cloud drift at 1 m/s, D Stability 3 min. delay to LFL at 150m 2% blast efficiency for open space 0.5 tons TNT LC50 at 5 psig PSO at 195 meters LC10 at 1 psig PSO at 291 meters

First Responders First responders generally have no idea of the layout (pre-planning). Assess situation. –Determine what hazards exist (Propane tank near barn). –May have to allow fire to burn out. –Must establish stand-off distance (1,000 meters). –May have to evacuate area. If possible, apply heavy water coverage to tank.