Disaster and accident scene safety assessment and hazard control
Scene safety assessment decides whether anyone, including you, becomes a second casualty. This domain tests your systematic size-up, hazard identification and zoning, and your ability to control or avoid hazards before patient contact.
Core rules
- Size up before you approach: what happened, how many patients, what hazards are present, what resources are needed, and what the scene will do next.
- Do a full 360-degree walk-around where possible. Approach from upwind and uphill, with a protected escape route behind you.
- Zone the scene: hot (contamination or active hazard, only PPE-equipped specialists), warm (decontamination and control), cold (support and treatment).
- Traffic: position apparatus to shield the scene, add cones and warning lights, wear high-visibility garments, and never turn your back on moving traffic.
- Utilities: treat every downed line as live and stay at least 10 m clear; smell gas, listen for hissing, and withdraw to a wide perimeter.
- Structures: sagging roofs, new cracks, jammed doors, and falling debris signal collapse. Do not enter a structure you have not assessed.
- Violence and secondary devices: a scene with one casualty in a public place may be a deliberate attack. Park away, use cover, and wait for law enforcement clearance.
- Treat size-up as continuous. Hazards change with wind, fire spread, and crowd movement; reassess after every significant event.
Worked example
A car has hit a pole and a line lies across the roof; the driver is conscious. Reasoning: assume the conductor is energized and the vehicle is the only protection. Keep everyone 10 m back, call the utility and fire service, tell the driver to stay inside and not touch metal, and do not approach until the line is confirmed de-energized and isolated. If fire forces evacuation, the driver jumps clear with feet together and hops away without touching the vehicle and ground at once.
Traps
- Rushing to a patient in the hot zone because she is screaming, which creates a rescuer casualty.
- Declaring the scene safe once and never reassessing.
- Entering a structure alone or without an accountability system.
- Standing between a vehicle and moving traffic while working.