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Training for accelerant detection canines and their handlers

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An accelerant detection canine (ADC) is trained to sniff out minute traces of ignitable liquid accelerants that may have been used to start a fire. Each dog is part of a team that is comprised of the canine and its handler. The handler is a law enforcement officer who has been trained to investigate fire scenes.

Initial phases of canine training

The training for an ADC begins long before it meets its handler. Training is based on a desired behavior (odor recognition) that brings a desired response (reward in the form of food or play).

  1. The first part of training is imprinting. The dog is initialized by being exposed to an ignitable liquid odor, taught how to alert, and receives a reward.
  2. Next, the dog is taught to ignore normal pyrolysis (burning) products that would be present at most fire scenes. Most ADCs are trained to respond passively to an odor by sitting (alert) until the handler commands “show me,” and the canine will point its nose or pat its paw where the odor is detected.
  3. Once the dog has been exposed to both ignitable liquids and pyrolysis products, the canine is taught to discriminate between these two accelerants and to alert to only nonpyrolysis accelerants.
  4. Finally, the handler is brought in to work with his or her dog on all this, over and over until it’s time to prove themselves through verification and certification.
ATF training facility

An accelerant detection canine and his handler in training with the Bureau of Alcohol, Tobacco, Firearms and Explosives.


A dog and handler are involved, either through proficiency testing or working a scene, in over a hundred trials per day. Detailed training records must be kept, and the records are critical in the courtroom. In addition to daily training, the ADC is certified annually. There are several certifying agencies, including:

Certification involves double blind recognition odor recognition and search exercise, scoring 100 percent.

On the job training

The training of the canine and handler really never ends. The ADC doesn’t receive food unless it earns it either through rigorous daily testing or while at an investigation. The canines are never fed unless exposed to an ignitable liquid. This is the primary reason that the dogs live with their handlers 24/7 because their training is compromised if they are provided with a bowl of dog food at a kennel or by someone other than the handler through training.

Investigating the scene

Canine teams have proven to be the most effective tool that fire investigators can use to locate accelerants. The fire investigator/handler will assess the fire scene, perform a cursory search for origin and cause, and ensure it is safe before the canine is used.

Once at the scene, the canine will begin its search after being given a command such as “seek,” and it will sniff for the odor of an accelerant. There are two searches: free search, where the dog sniffs randomly, and a directed search, where the handler steers the dog to a specific area that may have been missed.

If an accelerant is detected, the dog will “alert” its handler by sitting. Next, the handler asks the dog to show the exact source by the command, “show me.” The dog will pat its paw or point its nose at the spot, followed by praise and food (reward) for its work. The investigator or technician will collect the samples identified by the dog, and they will be sent to a lab to confirm the presence of an accelerant.

It is important to remember that the dog is a tool for fire investigators to use in locating the exact spot to collect samples that have a high probability of containing ignitable liquids. Analysis of the sample by a lab is the determining factor that confirms the presence of ignitable liquids.

Canine teams and National Fire Protection Association Standard 921 – Guide for Fire and Explosion Investigations

National Fire Protection Association (NFPA) 921 establishes the NFPA’s recommendations and best practices for the safe and systematic investigation and analysis of fire and explosion incidents.

In the 2014 edition, section outlines the proper use of canine teams as an ignitable liquid detection tool. The purpose of the canine/handler team is to assist with the identification of samples for laboratory analysis that may have been otherwise overlooked.

According to Richard Roby, a member of NFPA’s Technical Committee on Fire Investigations, the accepted methodology to validate a properly trained canine/handler team is through a double-blind confirmation of their ability to assist with the location and selection of ignitable liquid samples.

In order for the presence of an ignitable liquid to be confirmed the sample must undergo proper scientific analysis in accordance with ASTM E1387, “Standard Test Method for Ignitable Liquid Residue in Extracts from Fire Debris Samples by Gas Chromatography,” or with ASTM E1618, “Standard Test Method for Ignitable Liquid Residue in Extracts from Fire Debris by Gas Chromatography-Mass Spectrometry.” A sample is deemed validated only after laboratory analysis confirms the presence of an ignitable liquid.

Canines have been found to false alert to the products of pyrolysis, which contain many of the same chemical compounds as common ignitable liquids. However, considering that both substances are present on fire scenes, canines have a remarkable ability to discern between the two.

Some believe that canines are able to detect the presence of ignitable liquids at concentrations below the threshold for laboratory testing. Disregarding the issue of validation, the identification of ignitable liquids holds little evidential value because these substances are common to the built environment.

As such, canines should be utilized in conjunction with, and not in place of, other fire investigation and analysis methods [].