Lesson 3/Learning Event 1
LEARNING EVENT 1:
TEST FOR CHEMICAL AGENTS USING
THE M256 CHEMICAL AGENT DETECTOR KIT
Reconnaissance personnel will use the M256 kit in chemical reconnaissance operations. The M256
kit provides a quick means of identifying known chemical agents. This kit is issued at squad level.
It can detect the presence of blister, blood, and nerve agents. Specific agents which the kit can
identify are the mustards (H and HD), phosgene oxime (CX), lewisite (L), blood agents (AC and
CK), and the V and G type nerve agents.
A limitation of the M256 kit is that it cannot detect, nor be used for sampling, unknown agents. The
M256 kit also cannot detect choking agents. The kit consists of a plastic carrying case which
contains 12 individually wrapped sampler-detectors, a booklet of ABC-M8 VGH Chemical Agent
Detector Paper, and a set of operating instruction cards. The sampler-detectors contain the reagents
and indicators to identify specific chemical agents and color examples to indicate the presence or
absence of the agent being tested.
Operating instruction cards contain complete instructions on the operation of the kit. The M256 kit
and its components are shown in figure 8 on page 25 and the basic procedures for its use are
described in the following paragraphs.
The sampler must be inspected for rips or tears in the protective foil bag and for the expiration date.
Use of samplers with these deficiencies may give unreliable test results. The procedure for use of
the M256 kit is performed according to the following steps. The instructions on the instruction
cards and the sampler packets should be read if reconnaissance personnel do not fully understand
Step 1. Remove a sampler from the kit and its protective bag. Save the wrapper for reference
(figure 14 on page 43).
Touching the agent sampler test spots can cause incorrect test
results. Handle the sampler by the hinged protective strip with the
strip in the closed position.
Step 2. Swing the heater assembly away from the test spot and discard the two protective strips