What is the first action recommended upon hearing the word "GAS"?

The correct action to take upon hearing the word "GAS" is to stop breathing. This is critical because inhaling contaminated air can lead to immediate health risks, particularly in the case of chemical warfare agents or hazardous gas releases. By ceasing to breathe, an individual reduces the risk of gas entering the respiratory system, thereby minimizing exposure and potential harm.

After stopping breathing, the next steps often involve other safety protocols, such as sealing openings or using protective gear, but the immediate priority is to avoid inhaling the gas. Understanding the nature of the threat and responding proactively can significantly increase the chances of safety in a potentially dangerous situation.