Please allow me to inject my two cents here.
 
Dropping a "D" tank (or any compressed gas cylinder) and breaking off 
all or part of the REGULATOR would not be nearly as risky as breaking 
off the VALVE.  In the former case, the valve would still hold the gas 
in the tank; in the latter case the tank itself could become a lethal 
projectile, depending on how full it is.  If the valve is broken 
cleanly straight across the tank neck, the tank can go like a rocket 
(an "M" tank at 2000 psi could go through a brick wall w/o slowing 
down).  If the valve is merely deformed however, any gas escaping from 
the side of the valve would tend to propel the tank in an eeratic 
spinning not unlike the cheap "Catherine wheel" type fireworks.  Both 
of these situations are bad news!
 
Hope this helps....
 
Bob
--- TriToss (tm) Professional 10.0 - #204
(1:371/42.0)
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