Case Study: An Evaluation of Detection Dog Generalization to a Large Quantity of an Unknown Explosive in the Field

Abstract

Two explosive detection dogs were deployed to search a suspicious bag, and failed to detect 13 kg of explosive within. The aim of this research was to further evaluate this incident. First, dog teams (N = 7) searched four bags in a similar scenario. One bag contained the same 13 kg of explosive, two bags were blanks, and the other contained the training sample that the agency routinely used for training. All dogs detected the training sample, but most (5/7) did not alert to the 13 kg sample. Subsequently, dogs received two trials in a line up with a 30 g subsample of the explosive to evaluate whether they could generalize to a smaller quantity. Most dogs (6/7) alerted to the subsample at least once. Finally, dogs were trained with the 30 g subsample and later tested with the 13 kg sample. Only three dogs spontaneously generalized to the large sample after training with the small subsample. Dogs’ alert rate to the 13 kg sample was improved with training in subsequent trials with the 13 kg sample. This result indicates that explosive detection dogs may not generalize to a target odor at a significantly higher quantity relative to the one used in training, highlighting the importance of conducting such training.

A laboratory model of canine search vigilance decrement, I

“…Detection dogs have been trained to find a wide variety of hidden and cryptic targets such as invasive insects and weeds (Aviles‐Rosa, Nita, et al, 2022; Hanigan & Smith, 2014), narcotics (Furton et al, 2002; Jantorno et al, 2020), explosives (Aviles‐Rosa, McGuinness, et al, 2021; Lazarowski et al, 2021; Lazarowski & Dorman, 2014) and even missing persons (Jinn et al, 2020). In doing so, dogs are tasked to search a given environment to find and respond to their trained target odor, perhaps not unlike animals that must search for prey and productive areas to forage.…”

Enhancing Quality in Commercially Used Explosives Detection Dogs

“…Dog handlers report that sniffer dogs have difficulties in detecting large quantities of explosives unless they have been trained to do so [25]. The very small odor sources used in dog training for safety reasons could therefore result in large odor sources not being detected by the EDD.…”

Calibrating canines—a universal detector calibrant for detection dogs

“…Out of the aforementioned odor delivery mechanisms, two are able to precisely vary the concentration of UDC presented to the canine by altering the emission rate of 1-BO. This capability is important because recent data suggests that canines must be trained on varying concentrations of a target odor in order to find large/bulk quantities and small/trace amounts of odor operationally (27)(28)(29)(30). The COMPS form factor allows one to package the UDC liquid absorbed onto a substrate into permeable polymer bags of different thicknesses with permeation rates declining as the thickness of the bag increases.…”

“…Another significant benefit of the UDC is that its concentration is readily manipulable, which can be challenging for traditional target odor materials; Since recent data suggests that canines must be trained on varying concentrations of a target odor in order to find large/bulk quantities and small/trace amounts of odor operationally (27)(28)(29)(30), this feature is especially critical. Although training to a range of concentrations is important for all targets, the UDC and its relative ease of manipulation of concentration, may allow for training canines to engage in different search patterns based on odor volatility.…”