What color is most commonly used for barrier tape to mark the cold zone?

• A. Blue
• B. Red
• C. Yellow
• D. Green

Answer: (C)

Color coding for scene boundaries uses yellow to signal caution and establish a boundary around areas that are restricted but not immediately dangerous, like the cold zone. Yellow barrier tape is the most common choice because it is highly visible in most environments and quickly communicates to responders and bystanders that they should proceed with caution or stay out of the area. This standard visibility helps teams rapidly recognize safe zones and prevent cross-contamination between the hot (hazardous) and cold (safe) zones.

Other colors have different meanings in various contexts—blue may indicate mandatory actions, red often flags danger or a fire area, and green can denote safety or exits. But for marking a boundary that defines the cold zone specifically, yellow is preferred because its caution-signaling and prominence are universally understood across agencies and situations.