What should you do first when you hear the word "GAS"?

When you hear the word "GAS," the immediate and most critical action is to stop breathing. This response is crucial because inhaling potentially harmful substances can lead to serious health risks or incapacitation. By stopping breathing, you reduce the amount of contaminated air entering your lungs, allowing you more time to assess the situation and take appropriate actions afterward.

While covering your mouth is an important follow-up action to minimize inhalation, it is most effective when combined with first stopping breath intake. Seeking shelter is also essential, depending on the situation, but it assumes that you are already safe from the initial exposure. Running away quickly might put you at risk of further exposure if you're moving toward the source of the gas. Thus, halting your breath initially is the best immediate response to protect your health.