What is a critical safety consideration when working with propane gas?

The critical safety consideration when working with propane gas revolves around its behavior under pressure. Propane is stored as a liquid under pressure, and as it is released, it expands and can form a gas. This process can lead to increased pressure in closed systems, which poses a risk of leaks or ruptures if the systems are not properly designed to handle the changes in pressure. Understanding this characteristic is vital for ensuring safe storage, handling, and usage of propane, as high-pressure situations can lead to hazardous conditions, including explosions or fire.

In comparison, while other factors like vapor density and fuel capacity are relevant to propane safety, they do not pose immediate critical safety concerns like pressure expansion does. Vapor density, for example, relates to the behavior of propane in the air but is secondary to the hazards associated with high-pressure systems. Similarly, fuel capacity pertains to quantities of propane but does not directly impact the immediate safety measures necessary when handling the gas under pressure. Therefore, recognizing the risks associated with pressure expansion is paramount for ensuring safe operations involving propane.