Shelter-in-place is appropriate when

• A. It is unsafe to leave the facility
• B. It is sunny outside
• C. The alarm sounds but evacuation is advised
• D. There is a routine exercise scheduled

Answer: (A)

Shelter-in-place is used when leaving the building would expose people to danger, so staying inside protects everyone from the external hazard. It’s appropriate when it is unsafe to leave the facility because the threat is outside or at the perimeter, and moving through or into that area would increase risk. If told to shelter-in-place, move to a safe interior space, close doors and windows if possible, and follow any additional instructions until authorities say it’s safe to emerge.

Why the other options aren’t correct: sunny weather doesn’t pose an inside risk that sheltering would solve, so there’s no need to stay put. A routine exercise is planned and does not require shelter-in-place. If the alarm indicates evacuation is advised, you should evacuate as instructed rather than stay inside, since the situation requires leaving the building.