What is CSB-BLEVE ?
This is the Chemical Safety Board. They have an excellant Video of a Boiling Liquid Expanding Vapor Explosion. This has been a problem back in the 1970's I am still surprised that we are talking about it today in June of 2009.
Most people think that these BLEVEs occur in Chemical Plants. I have seen these in Ammonia Refrigeration Systems, on Rail Cars, and on FARMS. This one occured in a Turkey Hatchery. This resulted in 2 volunteer firemen (Fire Fighters) who were Killed !
Seven more were injured from the metal pieces of the tank struck Fire Fighters.
Teenagers joy riding on an All Terrian Vehicle (ATV) striking the piping system causing a leak and a near by pilot light igniting the propane. The "King Valve" failed to shut off. (Maybe because there was no maintenance on the valve. (See ASTM Standard)
All shut off valves should be replaced every 5 years. By the way this is the same shut off valve on the top of my Hot Water Heater. Let me check the date.
Do you know where all of your shut off valves are located as part of your emergency preparedness program (Maintenance Department) ?
Have a safe day. And try to find an "Unrecognized Hazard" in your home or office.