M256 CHEMICAL DETECTION KIT NEW ISSUE
Among the many tasks and responsibilities that each U.S. soldier has on the battlefield is to observe their surroundings for signs of CWAs (Chemical Warfare Agents). Warning signs vary depending on the chemical agent used and the delivery method. Automatic sensors can help, but there are other more conventional warning signs. These include:
– Bombs, rockets, or artillery shells not detonating with the characteristic force of high explosives.
– Spraying from low flying aircraft
– Dead animals with no apparent or observable cause of death
– Dead insects, especially those on animal carcasses
– Individuals who are experiencing or demonstrating symptoms consistent with CWA exposure
If the presence of CWA is suspected, individuals in the area are alerted so that they can don their protective equipment. Once everyone has suited up, the environment must be tested to determine whether a CWA is present and, if one is present, determine its type. One way to accomplish this task is to use the M256A1 Chemical Agent Detector kit.
The M256A1 kit is a manually operated chemical warfare agent detector system. It is used to determine whether it is safe to remove the protective mask following a chemical warfare agent attack, or as a confirmatory test after a chemical agent alarm has sounded. It is important to understand that the M256A1 IS NOT AN ALARM; it is a tool used after soldiers have received other warnings signals or indicators about the possible presence of chemical warfare agents (SUCH AS WITH THE M-8 and M-9 DETECTORS), and have responded by putting on their chemical protective clothing.
Aside from its carrying case, the M256 kit has three basic components:
ABC-M8 Chemical Agent Detector Paper (1 book – 25 sheets)
Operational Instructional Cards
M256A1 Kit Contents
The M256 kit can easily be carried by one person. It is contained in a high-impact plastic carrying case that measures seven inches high, five inches wide, and three inches in depth. The entire kit weighs 1.2 pounds. The kit can operate in temperatures ranging from minus 25 degrees Fahrenheit (-32 degrees Celsius) to 120 degrees Fahrenheit (49 degrees Celsius).
These components are designed so that an individual in full Mission Oriented Protective Posture (MOPP) can perform the appropriate tests.
M256A1 Vapor-Sampler Details
As its name implies, the M256 vapor-sampler is used to test vapors for the presence of nerve agents, blood agents, and blister agents. It is the primary testing device in the M256 kit. When issued, each new M256 kit contains 12 of these miniature chemistry sets, each sealed in a plastic laminated foil envelope. To minimize the chance of error, two persons should conduct a vapor-sampler test; one person reads the instructions and the second person performs the action. When necessary, one person can successfully operate the vapor-sampler. Vapor-samplers are used once and discarded.
The vapor-samplers plastic body holds the test components and connects the components of each individualized test to each other. Each sampler body has several glass ampoules, one hinged heater assembly, three test spots, one hinged protective strip, and a lewisite-detecting tablet with rubbing tab.
The glass ampoules contain various chemical solutions, called “reagents”, that react in predictable ways to the vapor forms of nerve, blood, and blister agents. The glass ampoules are used in the individual chemical agent tests in which two heater ampoules are used with the heater assembly in the blister agent tests. The ampoules are visible from the back of the vapor-sampler and are connected to their appropriate test spot by a channel molded into the plastic vapor-sampler body. Ampoules are crushed between gloved fingers to release the reagents contained within.
There are three test spots, one for each of three CWA tests. Each test spot is positioned on the sampler body to minimize the chance of cross-contamination between test spots and ensure both sides of each spot are exposed to the suspect vapor. To assist the operator in identifying the test being conducted, each test spot is shaped differently.
The name of each test (nerve, blood, and blister) is also printed above each test spot. Each test spot is made from a different material selected for its strength, sensitivity, functionality, and reliability. The nerve agent test spot is star shaped and made from filter paper. The blood agent test spot is round and made from a glass fiber filter. Lastly, the blister agent test spot is square and is made of chromatographic media.
The remaining components the hinged heater assembly, hinged protective strip, and a lewisite rubbing tablet are connected to the sampler body by rivets and a tab. The vapor-sampler’s heater is used with the blister agent test spot. The heater improves the evaporation of the blister agent test reagents, which helps the test achieve its required sensitivity. It generates heat through a chemical reaction from chemicals in the heater’s ampoules. It is riveted to the sampler body so that the operator can swing the heater over the blister agent test spot to conduct the test and swing it back out of the way to observe the test results. The protective strip is also riveted to the sampler body. It is positioned over the blood and nerve agent test spots to help protect them from accidental contamination. Finally, the lewisite detection tablet is covered by a protective plastic pull-tab that must be opened before use.
ABC-M8 Chemical Agent Detector Paper Details
M8 paper is used to test liquid substances for the presence of nerve agents and blister agents. It is similar to the litmus (pH) paper that is found in almost any laboratory in that a test result is indicated in both types of paper by a change in color. The difference is that M8 paper is specifically designed to react to nerve agents and blister agents in liquid form
M8 Paper Book
Each M256 kit comes with one booklet (25 sheets) of M8 paper. Unused M8 paper is tan in color and has three sensitive indicator dyes suspended within the paper. M8 paper responds (changes color) within 30 seconds of exposure to liquid G and V nerve agents and H or L blister agents. Each of these CWAs has a different level of acidity (pH). The detector dyes react to the different pH levels by changing to one of three colors. The color yellow indicates the presence of a G nerve agent; the color green indicates a V nerve agent. Exposure to either H or L blister agents produces a red color (see Figure 7). M8 paper does not have to be completely saturated with a liquid chemical agent to produce a test result. It reacts to a liquid measure as small as 0.02 milliliter (a drop or two).
The M256A1 kit is currently in use by U.S. soldiers on the ground in the Middle East, as well as by FEMA and First Responders.