Which of the following non-fire emergency actions is appropriate when being outside is unsafe?

Choosing to shelter in place is an appropriate response when being outside is deemed unsafe because it allows individuals to remain in a secure environment while minimizing their risk of exposure to the dangers present outdoors. This tactic is particularly useful in scenarios such as hazardous material spills, severe weather events, or biological threats, where leaving the building could put people in greater danger.

In contrast, options such as full evacuation and partial evacuation would require individuals to leave the safety of their current location, potentially exposing them to threats. In-building relocation may involve moving to a different area within the same building, which might not guarantee safety if the threat is pervasive throughout the structure. Therefore, sheltering in place is a crucial strategy that prioritizes safety by leveraging the existing structure to provide protection while waiting for the situation to improve.