What threshold defines a compressed gas in Class 2?

A compressed gas in Class 2 is defined as a substance that is shipped at a pressure greater than 41 psia (pounds per square inch absolute). This classification is crucial for determining the safety measures and regulatory requirements associated with handling and transporting compressed gases.

At pressures above this threshold, gases are highly pressurized and can pose risks such as explosions or leaks if not managed properly. Thus, the definition helps first responders and hazardous materials personnel to identify potential hazards quickly and implement the appropriate safety protocols.

The other options do not accurately represent the definition of compressed gases within the context of Class 2. For example, bottling gases at less than 41 psia would not qualify them as compressed gases, while atmospheric pressure handling does not consider the pressurized state needed for classification. Moreover, free air pressure standards do not relate directly to the classification criteria for a gas under pressure. Understanding this definition is essential for ensuring appropriate responses to incidents involving compressed gases.