Which of the following is not a hazard category during a structural collapse?

• A. Environmental hazards
• B. Physical hazards
• C. Biological hazards
• D. Structural hazards

Answer: (D)

In collapse scenarios, danger is usually grouped to help responders plan safety: environmental hazards include gases, heat, smoke and dust; physical hazards cover unstable debris, shifting loads, and the risk of collapse or objects moving; biological hazards involve contamination from victims, mold, or waste. The risks that come from the structure itself—the possibility of further collapse, hidden voids, or shifting structural elements—aren’t treated as a separate category in many training frameworks. Instead, they’re considered part of the physical hazards you must manage through stabilization, shoring, and careful assessment before advancing. That’s why the option describing structural hazards isn’t counted as its own distinct hazard category.