Many industries and laboratories work with compressed gas cylinders. A typical compressed gas cylinder filled to a pressure of 2,400 pounds per square inch (PSI) will contain a volume of gas, that at atmospheric pressure would occupy nearly 300 cubic feet, compressed into a volume of almost 2 cubic feet. This represents a huge amount of potential energy which, if released suddenly, can have catastrophic consequences.
For the dispensation of gas, these cylinders have a valve in one of their ends to which a regulator is attached. This valve is the weakest area of the cylinder. Its rupture can essentially turn the cylinder into a missile that can cause serious property or bodily harm, and the feats of errant gas cylinders have a storied lore in science and industry that includes claims of such cylinders going through walls. Such a claim was examined by the folks at Myth Busters in the video below.
A real case of a compressed gas cylinder in an industrial setting which was handled in an unsafe manner can be seen in the video below. The cylinder toppled over breaking its valve, and the resulting explosive release of gas made it go airborne!
An additional hazard occurs if the release of gas takes place in an enclosed not very well ventilated space. A gas in the cylinder such as nitrogen can displace all the oxygen-containing air and produce asphyxia. To avoid these situations compressed gas cylinder handlers have follow specific safety protocols.