Fourth Generation Agents

Field Detection

Field Sample

Field Detection and Sampling

  • Detecting FGAs is more challenging than detecting other chemical agents. There is a limited fielded capability within hazardous materials teams to detect, characterize, and identify FGAs.
    • M8 paper may be useful in detecting liquid FGAs. Upon exposure to a liquid, a yellow/green or green/blue color is indicative of an FGA, and may shift to a more yellow color over time (up to 10 minutes). This color change is further indicative of an FGA versus VX.
  • Failure to detect does not mean that FGAs are not present.
  • Monitoring, sampling, and analysis by U.S. government specialized assets may be the only way to determine if FGAs are present. Initial field detection of FGAs may be possible, but more definitive identification of the presence of an FGA will require specialized resources.


  • Liquid FGA on M8 Paper - 10 seconds
    Liquid FGA on M8 Paper — 10 Seconds

    Liquid FGA on M8 Paper - 10 minutes
    Liquid FGA on M8 Paper — 10 Minutes
Find more information on this substance at: Hazardous Substances Data Bank , TOXNET , PubMed