Which of the following is an automatic criterion for calling a MAYDAY?

The correct choice highlights the scenario where a member is in a low air alarm and unsure of their location. This situation is critical because it indicates an immediate risk to the firefighter's safety. When a firefighter's air supply is low, their ability to breathe can be severely compromised, leading to disorientation and panic. If they are also unsure of where they are, the risk of becoming incapacitated increases significantly.

Calling a MAYDAY in this context is vital because it alerts teams to the need for immediate assistance, allowing for a coordinated response to find and extract the at-risk firefighter. This criterion underscores the importance of maintaining situational awareness and the necessary support systems in high-stress environments like firefighting operations, where quick decision-making can mean the difference between life and death.

Understanding this helps ensure that all team members are equipped to handle emergencies effectively, reinforcing the importance of protocols for recognizing and responding to threats during firefighting efforts.