Electrical Equipment and Products
Electrical Extension Cords and Devices

Prior to entering the fire scene, don appropriate PPE.

 

Detailed Procedure

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At the electrical service panel:

1. Visually examine the electrical service to ensure all circuits are de-energized and electrical products can be safely collected.

2. Photograph the panel.

3. Sketch or diagram the scene and evidence to be collected, noting the circuit of interest.

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Proceed to the electrical extension cord or device collection site. Electrical extension cords or devices may bear fingerprints or trace evidence and therefore should be handled as little as possible and with gloved hands, avoiding contact with boundary surfaces as much as possible. 

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To collect the electrical extension cord or device:

1. Photograph the area as found.

2. Apply a non-contact voltage tester to the extension cord or device and any supplying receptacle as a presumptive test for the presence of electrical current. Use a multimeter as appropriate. If current is not detected, proceed.

3. To facilitate potential collection in the future, document which branch circuit overcurrent protection and receptacle supplied the subject extension cord or other device like a relocatable power tap.

4. When an extension cord or device is plugged into a receptacle, the receptacle is typically collected as one assembly with the cord or device attached. Only unplug the cord or device in the field if all interested parties have been notified and agree. 

5. Use the general to specific methodology to photograph the extension cord or device in place. Continue photographing the collection process as you collect the cord or device.

6. Excavate the entire length of the cord or area around the device to be collected.  Locate all components, including plug blades, blade receivers/rails, and conductors. Sift the debris with various sized mesh screens, if necessary.

   1. ​If the extension cord is fragmented, use color-coordinated zip ties to document matching connection points.

   2. If portions of the cord or device are embedded in or adhered to a substrate and cannot be easily detached, cut away a piece of the substrate with a wide margin around the cord or device and collect it with the cord or device.

7. If you are also collecting the receptacle the extension cord or device is or was plugged into:

   1. ​If the receptacle is still attached to its mounting in an immovable object, follow the procedure for freeing the receptacle from its mounting first.

   2. Note line side vs. load side and note any devices serviced by the extension cord or device.

   3. Place witness marks on either side of where the electrical service lines will be cut, then cut between them.

   4. Once the receptacle is free, proceed with collecting the entire extension cord or device assembly (see step 10).

   5. If the supplying receptacle removed from the wall is no longer attached to the extension cord, package the receptacle separately. Secure the receptacle to a backer board before placing it in the container so it does not move around and become damaged in transport.

8. When you are ready to collect, gather the containers and tools necessary. Typically, boxes or zip plastic bags are used.

9. Carefully remove the extension cord or device and any attached items from their location.

10. Gently coil or serpentine the cord. Be careful when handling brittle wire so you do not damage it.

11. Use zip ties or similar method to secure the cord or device to a backer board. If the extension cord or device is still attached to an electrical product, collect them together as a combined unit into an appropriately sized box. If needed, secure the backer board inside the box to prevent damage to or alteration of the cord or device.  

    1. ​Alternatively, secure the cord or device to a backer board and place it in an appropriately sized bag. Zip the bag closed.

12. If collecting any loose components, they can all be placed in the same small bag within the main bag or container.

    1. ​Place the components bag in the box or bag with the extension cord or device. If needed, secure the components bag to prevent movement.

13. Seal the box or bag with evidence security tape.

14. Initial and date the tape.

15. Label the packaging with case information according to your organization’s SOP.

16. Store the collected items in a secure location until you can transport them to the laboratory. 

17. Transport the collected items to a climate-controlled, secure evidence storage facility consistent with your organization’s guidelines. If you will be shipping the evidence to a lab, consult the lab for advice on how to package for shipping so the evidence is not damaged in transit.

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After you have collected the electrical extension cord or device assembly, collect the branch circuit overcurrent protection device, if appropriate:

1. Apply a non-contact voltage tester to the panel as a presumptive test for the presence of electrical current. 

2. Use a multimeter as appropriate. 

3. Witness mark the overcurrent protection device on the circuit of interest to denote which one it is. 

4. Use zip ties or a paint pen to witness mark the branch circuit line. 

5. With diagonal cutters, cut between the witness marks. 

6. Pry the overcurrent protection device and the attached branch circuit wire piece out. Place in a zip bag and close. 

7. Label the bag according to your organization’s SOP. 

8. Seal the bag with evidence tape. 

9. Initial and date the tape.

10. Store the collected items in a secure location until you can transport them to the laboratory.

11. Transport the collected items to a climate-controlled, secure evidence storage facility consistent with your organization’s guidelines. If you will be shipping the evidence to a lab, consult the lab for advice on how to package for shipping so the evidence is not damaged in transit.

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If the electrical extension cord or device will also be examined for ignitable liquid residue, please consult the laboratory for the proper collection procedure. Items should not be air-dried or packaged in an air-permeable container if they will be examined for ignitable liquid residue.

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Laboratory testing of electrical extension cords or devices:

Examination of extension cords or devices in a laboratory environment may provide an opportunity to evaluate and document melting or electrical activity with the assistance of light microscopy, x-ray, computer tomography, metallurgical evaluation, or SEM/EDS analysis.