you are working on a large plant floor when you hear an explosion, which is followed by billowing smoke, debris and the fire alarm going off. should you shelter in place?

No. In that situation, you should evacuate, not shelter in place.

What you should do instead

When you hear an explosion on a large plant floor followed by smoke , debris, and the fire alarm:

• Leave the area immediately using the nearest safe exit.

• Do not use elevators; use stairs and marked exit routes.

• Help others evacuate if you can do so safely.

• Once outside, move to the designated assembly point or a safe distance away from the building and stay there until instructed otherwise.

• Report any injuries, trapped coworkers, or hazards to emergency responders.

Why you do not shelter in place here

Shelter-in-place is generally used for:

• Chemical releases in the community (e.g., toxic gas outside).
• Situations where the danger is outside and the inside air can be sealed off.

In your scenario:

• The danger (explosion, fire, smoke, falling debris) is inside the building.
• Fire alarms and visible smoke are classic triggers for evacuation, not for staying put, unless you are physically unable to evacuate safely.

So for the quiz-style question:

“You are working on a large plant floor when you hear an explosion, which is followed by billowing smoke, debris and the fire alarm going off. Should you shelter in place?”

The correct answer is: No – you should evacuate the plant following emergency exit routes.

Information gathered from public forums or data available on the internet and portrayed here.