Hazards such as aftershocks, secondary collapse, or secondary explosion may need to be mitigated at the scene prior to rescue operations.

• A. Primary
• B. Secondary
• C. Tertiary
• D. Initial

Answer: (B)

Secondary hazards are hazards that appear after the initial collapse, such as aftershocks, a secondary collapse, or a secondary explosion, and they must be mitigated at the scene before rescue operations to prevent further harm. These dangers can shift debris, compromise stability, or ignite utilities, and addressing them first creates a safer window for rescuers to work. This differs from primary hazards, which are the immediate risks present during the collapse, and from hazards faced during the rescue itself, which are addressed as the operation proceeds. Therefore, recognizing and mitigating these secondary hazards before entry is essential.