What are the evacuation distances for Large IED (around 50 pounds)?

• A. Mandatory 70 feet; Preferred 1200 feet
• B. Mandatory 150 feet; Preferred 1850 feet
• C. Mandatory 320 feet; Preferred 1900 feet
• D. Mandatory 500 feet; Preferred 2500 feet

Answer: (B)

Evacuation distances around large IEDs are determined by blast hazard zones with two levels: a mandatory minimum and a preferred safety distance. For a Large IED around 50 pounds, the minimum evacuation distance is 150 feet. This baseline helps ensure people are far enough away from the blast to reduce exposure to overpressure, fragmentation, and debris. The preferred distance is a much larger buffer, about 1850 feet, to account for uncertainties such as miscalculation of explosive weight, device configuration that could increase hazards, potential secondary devices, and environmental factors. Following the larger buffer greatly lowers risk to bystanders and responders during assessment and render-safe actions. The other options either understate the required minimum or propose distances that don’t align with typical field guidelines for this size of device.