Warfighters and law enforcement personnel encounter many situations where they need to assess and determine if a situation is hostile or benign. Currently available field explosive detection kits are awkward, prone to mistakes, and difficult to use in non-ideal conditions. Accurate detection is easily thwarted by wind, improper staging areas, distractions, and contaminated hands. Current test devices require sampling gloves, are difficult to carry (multiple cans or bottles and sampling swabs), can easily be used incorrectly (adding reagents in the wrong order or the wrong quantity), and often require access to a flat surface for use.

(a) To use the device, the cap/swab is removed and used to swab a surface or substance. (b, c) The cap/swab is replaced and the ampoules are depressed in order, checking after each one for a colorimetric response.

A multi-test field kit was developed that is small, lightweight, rugged, and has a one-year shelf life with the ability to operate in a variety of field environments (hot, cold, high/low humidity). The field colorimetric test device does not require gloves and is easy to use, accurate and foolproof, refillable, disposable, and can detect anything that gives a colorimetric response to solid or liquid reagents. The system is also adaptable — similar to a first-aid kit — and comes in a convenient, all-in-one packet.

Having an all-in-one unit, rather than the multiple cans or bottles of reagents and separate sampling paper, means only one small packet is necessary. With individual packaging and robust design, users can carry multiple kits in a pocket, backpack, or glove compartment.

With the ampoule selection device, reagents can only be added in the correct order. Typically, the chemistry does not work if the reagents are added out of order, so if the reagent cans or bottles are mixed up, the test will not provide accurate results. The new design eliminates the potential for mixing up the reagents.

The sampling swab is incorporated into the cap. A sample can be taken, the cap replaced, and analysis can be done at a later date while the sample is protected. This feature also eliminates the need for sampling gloves, since the exterior of the cap is attached, eliminating the likelihood of unintended contamination.

The prototype units are set to test for explosives (e.g., TNT, TATB, RDX, HMX, nitroglycerin, nitrocellulose, ammonium nitrate, urea nitrate, etc.); however, the ampoules can be filled with other reagents, and the same design can be used to detect drugs, peroxide explosive, chlorate, bromate explosives, etc.

For more information, contact Marti Elder, CLP, at This email address is being protected from spambots. You need JavaScript enabled to view it.; 406-586-7621.


Tech Briefs Magazine

This article first appeared in the September, 2018 issue of Tech Briefs Magazine.

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