What are the three requirements for the "2 in, 2 out" rule regarding exterior firefighters?

The correct choice highlights the essential elements of the "2 in, 2 out" rule, which is a critical safety regulation for firefighting operations, especially when dealing with incidents in Immediately Dangerous to Life or Health (IDLH) atmospheres.

The first requirement, being outside the IDLH atmosphere, ensures that firefighters stationed outside are not put at risk of exposure to hazardous conditions while still being close enough to assist. The second requirement, accounting for interior teams, emphasizes the importance of knowing who is inside the structure and their status. This helps maintain situational awareness. The final requirement, remaining capable of rescuing interior teams, stresses that the exterior firefighters must be prepared to perform rescues if necessary, reinforcing the safety of all personnel involved.

Other options do not accurately capture these pivotal components or focus on peripheral aspects rather than the specific mandates of the "2 in, 2 out" rule. By ensuring these three criteria are met, firefighters can operate within a framework that prioritizes life safety and effective incident management.