Definition - What does Compressed Gas mean?
Compressed gasses are gasses that are stored under pressure in cylinders. The three major types of compressed gasses are liquefied gasses, non-liquefied gasses and dissolved gasses. The pressure of the gas in a cylinder is usually recorded as pounds per square inch gauge (psig) or kilopascals.
Safeopedia explains Compressed Gas
Liquefied gasses are liquid at normal temperatures when they are inside cylinders under pressure. Common liquefied gasses include ammonia, chloride, propane and nitrous oxide. Non-liquefied gasses are also known as compressed, pressurized or permanent gasses. Oxygen, nitrogen, helium and argon are all examples of non-liquefied gasses. Acetylene is the only common dissolved gas and is very unstable chemically.