LPG Tanker Fire - I Had It Right On The Money

YES, you seem to have got it right!
My questions are?
I was there also and heard three explosions. One relatively Large one and two secondary ones! I witnessed flames in a Palm tree (close to a Power pole directly adjacent to the apartment building, at first I thought a transformer blew up)and flaming material on the roof of several vehicles around one hundred feet from the LPG delivery truck! Almost immediately a fire ball flashed from the third floor apartment(fourth level) in a rather large and obese fire ball shooting out thirty feet or more over the street and well over a fifty feet high. Your information on the valve and the flow of propane seems to hold true. Propane usually flows down hill like water and the vapors usually range from six to eighteen inches off the ground!! Except it does not explain the fires in the third and first floor apartments(why was the second floor apartment spare from the initial fire?)
The fire on the third floor apartment was burning very, very intensely and gutted the apartment(windows blown out) before or about the time as the cab on the LPG tanker truck caught fire! The First floor apartment (windows were not blown out)caught fire a soon after!
What type of combustible material were stored and used on the third floor! Propane does not travel uphill unless pumped. The vapors at that height would have dissipated to a state that every thing could have been a ignition source in a confined area between the truck and the building! Except that the third floor apartment windows blew out wards and the intense fire was fueled by some thing more that mere Propane!
Also the damage inflicted upon the vehicles does not point directly to the explosions or does it?
There were the three explosions, what did they trigger?
Usually there is fire then explosions when it comes to propane mishaps! In this case three Explosion occurred first??? NO real blast damage from flying debris! Seems awfully strange that there was not any form of blast or thermal blast wave damage in the immediate area.
Just questions and observation on my part!
A former sale Representative of CALGAS, in my past life!

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I might add that Propane (and Butane) have very narrow limits of inflamablity. I.e. very dificult to ignite unless the fuel/air mixture is precise.

Most LPG "explosions" are "flash fires". and occur in open spaces. The give off a "Whump" sound. If you are within the volume of expanding products of combustion you will recieve flash burns on unprotected areas of flesh and will likely be knocked on your ass!

A Propane tank explosion is almost impossible to set off intentionally let alone by accident as the pressure INSIDE the tank has to drop to atmospheric or below to allow air TO GET INSIDE the tank to support combustion..

However accidents do happen.
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