What is a recommended practice when establishing perimeters at a fire scene?

• A. Initial perimeters should be drawn narrowly
• B. Perimeters should be limited to the immediate area
• C. Initial perimeters should be larger than necessary for investigators
• D. Perimeters should be set after evidence collection

Answer: (C)

Setting an adequately sized initial fire scene perimeter is about protecting evidence and ensuring safety. Establishing a boundary larger than what investigators might think is necessary gives you room to identify the full extent of the scene, potential ignition sources, and areas where debris or heat could have extended. It also creates a controlled area for entry and exit, reduces the chance of bystander contamination, and provides space for documenting, photographing, and collecting evidence without accidentally stepping outside a secured zone. As the investigation unfolds, you can adjust the boundary if needed, but starting with a larger buffer helps prevent loss or contamination of critical information.

Drawing a tighter perimeter risks missing relevant evidence or hazard areas; limiting to the immediate area may overlook connected evidence or safety concerns; and setting the perimeter after evidence collection invites contamination or disturbance of the scene.