1. Identify Chemical Agents
Using M256-Series Chemical Agent Detector Kit

2. Conditions: Given a tactical environment or a simulated chemically (nerve and blister) contaminated area and M256-series chemical agent detector kit, protective mask, mission-oriented protection posture (MOPP) gear or chemical protective ensemble, watch, TM , and FM 3-5.
Standards: Identified chemical agents using an M256 series chemical agent detector kit without becoming a casualty.

3. References: FM 3-5 and TM 3-6665-307-10
Risk Assessment: Low

4. PERFORMANCE STEPS
Perform before-operation preventive maintenance checks and services (PMCS) according to TM
2. Prepare the kit for use.
a. Read all the instruction cards in the kit.
b. Remove one sampler detector from the kit, and read the instructions printed on the bag.

5. WARNING
Do not expose the sampler detector to heavy rain or other forms of water. Test results could be tainted.
Do not touch the sampler detector test spots. Dirt and oil from your gloves will cause test results to be tainted.

6. c. Remove the sampler detector from the bag (save the bag and use the instructions printed on the outside). Discard the sampler detector if there are broken or missing ampules, missing spots, or crushed reagent channels, or if the blood agent test spot is pink.
3. Test for toxic-agent vapors.
a. Swing out the heater and remove and save the two heater pads (used for breaking glass ampules). Swing the heater back in. Keep the protective strips over the spots.

7. b. Remove the pull tab (marked 1) to expose the lewisite detecting tablet. Bend the tab (marked 2) over the lewisite detecting tablet, and rub the upper half of the tab until a mark is visible.
WARNING
Before breaking the glass ampules (except heater ampules), place one heater pad on each side of the sampler detector, covering the ampule to be broken. The pads will prevent pieces of glass from cutting your gloves and hands.

8. c. Hold the sampler detector with the test spots and the arrow pointing up. Crush the four center ampules (marked 3).
d. Turn the sampler detector so the arrow points down. Use the heater pads to squeeze the ampules, forcing liquid through the formed channels into the test spots.

9. e. Hold the sampler detector with the arrow pointed down and your thumb on the protective strip over the middle test spot.
(1) Swing the heater away from the blister test spot.
(2) Activate the first heater ampule (marked 4) by crushing one green ampule, swing the heater back over the test spot, and leave it in place for 2 minutes. Hold the sampler detector to one side to avoid the vapor. Do not use the heater pads to crush green ampules.

10. WARNING
Do not use the heater pads to crush the green ampules
(3) Swing the heater and the protective strip away from the test spots.
Do not hold the sampler detector in direct sunlight while exposing the test spots, because test results could be tainted

11. f. Expose the test spots to air (shield them from direct sunlight) for 10 minutes. Lay the sampler detector down or hold it by the hinged protective strip.
g. Crush the second green ampule (marked 4) after 10 minutes and immediately swing the heater over the blister test spot Swing the heater away from the test spot after 1 minute.
WARNING
Do not use the heater pads to crush the green ampules.

12. h. Hold the sampler detector with the arrow pointing down and the test spots exposed. Use the heater pads to crush the remaining ampules (marked 5). Wet the test spots by squeezing the ampules and forcing liquid onto them.
i. Bend the tab (marked 2) over the lewisite detecting tablet, and rub the bottom half of tab until a mark is visible.
j. Turn the sampler detector upside down, and compare the colors of the test spots (including the lewisite tab) with those shown on the sampler detector.

13. (1) Compare the blood agent (round) test spot after about 10 minutes exposure time.
(a) Yellow or orange sometimes occur when no agent is present.
(b) Pink or blue must be present to indicate blood agents. Any combination of colors or a rainbow effect that includes pink or blue should be considered as a positive blood agent test.
(2) Compare the lewisite test after about 10 minutes exposure time. Look very closely; at low concentrations, the color change may be very slight.

14. Note. Blister agents (H and CX) develop color immediately after all ampules are broken.
(3) Wait 3 minutes for the nerve-agent test.
NOTE. Disregard any small blue or blue-green areas under the plastic rim of the nerve agent spot.
(a) M256: If a peach color develops, a positive nerve test is indicated.

15. (b) M256A1: If no color develops, a positive nerve test is indicated.
4. Report the results to your supervisor.
5. Dispose of the materials by one of the following methods:
a. Dispose of expended or unserviceable materials according to Federal, state, and local laws; military regulations and publications; host nation laws (if more restrictive than U.S. laws); and the local standing operating procedures (SOP). As a minimum, place used decontaminating materials in a sealed plastic bag and label it with the contents.

16. b. Dispose of contaminated hazardous waste materials according to FM 3-5.
6. Perform after-operation PMCS according to TM
a. Ensure M8 detector paper is present.
b. Ensure there are at least four sample-detectors in the kit.