In a hazardous materials or decontamination area, which statement correctly defines hot, warm, and cold zones?

• A. Hot zone is the clean area; warm zone is the contaminated zone; cold zone is the transition area.
• B. Hot zone is the contaminated area; warm zone is the decontamination/transition zone; cold zone is the clean area.
• C. Cold zone is the contaminated area; hot zone is the decontamination.
• D. Warm zone is the clean area; hot zone is cold.

Answer: (B)

Understanding these zones is about creating a controlled flow so contamination doesn’t spread. The hot zone is the area with the highest level of contamination and access is tightly restricted; responders wear full PPE there because that's where the hazard is active. The warm zone acts as the decontamination/transition area between the hot and the clean zone; it’s where decontamination happens and PPE is removed or adjusted as you move toward safety. The cold zone is the clean area where people and equipment are free from contamination and can operate safely.

This description fits the statement that hot zone is the contaminated area, the warm zone is the decontamination/transition area, and the cold zone is the clean area. The other configurations would place contamination or decontamination in the wrong zones, undermining protection and proper flow.