On Wednesday, January 23, 1996 the following tests were performed at the offices of “Origin & Cause” in Ancaster, Ontario.
To try and determine the ability of a dog trained in the detection of ignitable liquids in term of the sensitivity for searching out various dilution’s of an ignitable liquid.
To compare the above sensitivity of the dog to the sensitivity of analyses currently conducted by Passive Fiber sampling and GC/MS at Actlabs Organics.
- the office flooring was carpeted. The carpet was greater than 1 year in age and well maintained,
- the office consisted of a large central carpeted area and several adjoining offices carpeted with the same material,
- aside from the handler up to eight other people were present,
- tests were conducted by directly pipeting the water based test solutions onto the carpet,
- testing was done between 10:45 and 11:45 am,
- testing was done singly i.e., each test was spotted and then the dog allowed to search the area approximately one minute later, then the next test was spotted. There was about 5 minutes between tests,
- testing started with the most concentrated sample and proceeded to more dilute concentrations,
- concentrations were within an error of ~5%,
- the water used for dilution’s was 18 megaohm Ultrapure Deionized water,
- non-weathered gasoline and non-weathered low-odour kerosene was used,
- all searches were conducted by “Smoke”, a German Shepherd,
- all solutions were kept in a separate office behind a closed door during searches.
A. 1 Part Gasoline : 1,000 parts water (1 : 1,000)
B. 1 : 10,000
C. 1 : 100,000
D. 1 : 1,000,000 (1 part per million or 1 ppm)
E. 1 Part Low-Odour Kerosene : 5,000 parts water (1 : 5,000)
F. 1 : 50 (Gasoline)
G. Odourless Lamp Oil (No dilution)
Using a fresh glass pipette for each test, the first spot used 3 drops of solution “F (1) “. This first test did not result in a response from the dog. This area was heavily traveled and was between the boardroom, washroom and near the front entrance which may have been detrimental to the search. It was also discovered that a person in the room had come in contact with gasoline, with their shoes, that morning and had definitely contaminated an area within 5 feet of F(1). It was also felt that 3 drops directly on top of each other might be too small in terms of surface cross-section and/or too small a liquid content to be a realistic test. All subsequent tests used ten drops of the solution spread over a circular area approximately the size of a quarter. The initial solution was re-spotted in a new location using 10 drops at “F(2)”. As an example using this method for solution “B”, ten drops of 1:10,000 was used. Each spot was prepared by one person for consistency.
The dog could detect a concentration between 1:100,000 and 1:1,000,000 of gasoline. Currently Actlabs Organics can detect gasoline at 1:100,000 at approximately five times above the method blank or background.
It is logical that the sensitivity of the dog will vary with different ignitable liquids. In support of this there appeared to be a more immediate detection of 1:5,000 of Kerosene than the 1:1,000 of Gasoline. It is also probably true that different dogs will have different limits of sensitivity.
The comparison of the sensitivity of this dog with the current laboratory analysis is very good and is within a factor of ten. Using these findings, and perhaps an additional experiment with the dog(s), the analysis by Actlabs Organics will be further tuned to try and achieve the same sensitivity as these highly trained dogs and thus be an even better confirmatory test.