A picture-perfect BLEVE caught on drone cam. A storm chaser captured this fire and BLEVE while traveling to chase a storm in Canada. This was in Sidney, MT, and may be the best training video showing a BLEVE (he has even slowed the footage down so we can see it in slow motion).
We can see the tell-tale sign of a BLEVE, specifically a “Hot BLEVE”. A fire impinging on a pressure vessel containing a gas (in this case, a flammable gas) stored as a liquid under pressure. As the fire impinges on the vapor space of the tank (which we can clearly see), the metal weakens and begins to blister/bulge due to the expanding liquid/gas pressures inside the tank. The metal eventually fails, and we see the white cloud form, which is well above the flammable gas’s UEL. As the cloud expands and mixes with the ambient air, the flammable gas enters its flammable range and ignites, creating a large fireball. But don’t be fooled by the big BOOM and fireball – the BLEVE has already occurred. The material involved does NOT have to be a flammable gas! Any gas, stored or a liquid, inside a Pressure Vessel is a candidate for a BLEVE.
NOTE: Non-Flammables, such as CO2, N2, Ar, will BLEVE, we just don’t have to be a big fireball at the end.
News accounts state this BLEVE was felt 10 miles away.
My Observation: This tank appears to be out of its saddles, and the PSV is discharging horizontally. Perhaps a previous tank explosion dislodged this tank from its saddle and severed the liquid propane piping, causing the “jet fire” we see spreading across the ground.
