What does a "Mayday" call signify in firefighting?

A "Mayday" call in firefighting is a critical emergency signal that indicates a firefighter is lost, trapped, or facing an imminent life-threatening situation. This term originates from aviation distress signals and has been adapted in the firefighting community to prioritize the safety of personnel in dangerous situations. When a "Mayday" is declared, it triggers an immediate response from command and other team members to locate and assist the individual in distress, emphasizing the urgency and seriousness of the situation.

In contrast, the other choices represent different scenarios in firefighting operations. Reporting fire extinguishing success addresses the status of the fire, routine check-ins with command are part of normal operational communication, and requests for additional equipment focus on logistical needs rather than emergency response. Each of these does not carry the life-threatening implications associated with the "Mayday" call, which is solely dedicated to ensuring the safety and rescue of firefighters in peril.