High-sensitivity, high-selectivity detection of chemical warfare agents

We report high-sensitivity detection of chemical warfare agents nerve gases with very low probability of false positives (PFP). We demonstrate a detection threshold of 1.2 ppb 7.7 ug/m3 equivalent of Sarin with a PFP of <1:106 in the presence of many interfering gases present in an urban environment through the detection of diisopropyl methylphosphonate, an accepted relatively harmless surrogate for the nerve agents. For the current measurement time of ~ 60 s, a PFP of 1:106 corresponds to one false alarm approximately every 23 months. The demonstrated performance satisfies most current homeland and military security requirements.