Quote Originally Posted by Aggie
another risk, albeit small, is if any form or a oil or grease should hit the top of the cylinder at the connectrion. It can cause it to start a fire and explode. Helps to have had a brother in law who was a fireman.
No! Neither Argon not Nitrogen are flamable in that respect. In fact, sudden release of pressure of these systems will cause a cooling effect - sometimes so great that the temperature can approach the temperature of liquid gases. The main problems stem from flying objects.

On the other hand high pressure air can certainly cause a fire if mishandled. That is one of the most underestimated hazards in my old engineering business. And forget hp Oxygen! Oxygen has to be one of the most hazardous materials in daily use. No smileys here. I worked with these compressed gasses at pressures exceeding 18,000 psi without incident, but I have been witness to oxygen fires (read:explosions). I was commissioned by the U.S. Navy to solve a problem on their electrolytic oxygen generators used aboard submarines. I now hold the patent on a new design still in use as far as I know. Because the generators also make Hydrogen at high pressures, no one else wanted to take on the project I found that the problem was _not_ the Hydrogen but the Oxygen. Actually, Hydrogen is a pussy-cat compared to hp Oxygen, which is unpredictable. Hp air has similar properties.

Whew! Got that off my chest.