During a chemical or radiological incident, which protective action is intended to keep people indoors to minimize exposure?

• A. Evacuation moves people to a location outside the affected area
• B. Shelter-in-place keeps people indoors to minimize exposure
• C. Lockdown
• D. Shelter and Evacuate

Answer: (B)

Shelter-in-place is the protective action designed to keep people indoors to minimize exposure during a chemical or radiological incident. By staying inside, you limit contact with contaminated outdoor air and reduce inhalation of toxic substances. If possible, move to an interior room, close doors and windows, turn off outdoor air ventilation, and seal gaps to prevent contaminants from entering. This approach leverages the building as a barrier and, in a radiological release, provides shielding from external radiation. Evacuation would move people into outdoor air that could be contaminated, which can increase exposure. Lockdown focuses on security concerns rather than exposure to hazardous substances, and a mix like “shelter and evacuate” isn’t a standard protective action for this scenario.