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Fire Scene Evidence Collection Guide

Ignitable Liquid Residue & Fire Debris


Detailed Procedure:

Baseboards can adjoin many different types of flooring. Please follow the procedure for collecting that flooring as well as the baseboards.

To collect the baseboards:

  1. Select a productive sampling area. Productive sampling areas include the following:

    • Within an area of ignitable liquid indicators, such as a suspected pour pattern

    • In an area where ignitable liquid may collect or pool, such as the lowest point on the grade

    • Edge of a burn pattern or suspected pour pattern

    • At junctures with furniture and walls

    • Joints

    • Vertical grain

    • On stair treads at the joint between riser and tread

  2. Select appropriate tools, such as a chisel and mallet, to cut out the sample.

  3. Select a new, metal paint can container.

  4. Clean all tools before sampling, or use new, disposable tools.

  5. Photograph the sampling area, measure, and record measurements on the diagram with at least two fixed points of reference.

  6. Wear new, unused, clean latex or nitrile gloves. Be sure to change the gloves between every sample you collect to avoid cross-contamination.

  7. Use the chisel and mallet to break into the wood, preferably ½" on either side of the baseboard, as liquids tend to collect in seams, and up to the joint. Break out a wood sample that includes the material in the joint, the shoe molding (if present), and the area of the floor directly under and in front of the baseboard. Also collect the material under the baseboard that may have soaked up an ignitable liquid, such as sheetrock or lath/plaster. You may need to cut out this area with a knife or small saw.

  8. Place the sample in the paint can. If the sample is large, break it into smaller pieces to fit into the container. Make sure to leave 1/3 headspace in the can.

  9. Clean the lip of the can using a clean screwdriver or other suitable tool.

  10. Gently tap the top of the lid with a clean rubber mallet to seal it. Do not dent the can because it may compromise the seal.

  11. Seal the container with evidence tape. Initial and date the tape.

  12. If possible, collect a comparison sample of the same baseboard from a location not in the room of origin. A comparison sample will help the laboratory exclude compounds occurring naturally in the baseboard. This sample should be collected in a separate container and using a new, unused pair of gloves and a properly cleaned or new tool.

  13. Label each container with identifying information, including case number, date, exhibit number, a brief description including recovery location, and your name.

  14. Store the item(s) in a secure location, such as a locked evidence van or your vehicle, until you are able to transport it to the laboratory.

Laboratory examination of baseboards for ignitable liquids:

Wood floors can be tested for ignitable liquids using gas chromatography mass spectrometry. This test can determine the classification of the ignitable liquid.


interFIRE. "Evidence Sampling for Ignitable Liquids Testing." Online Training Module, 2013:

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