The goal of this test was to give emergency responders interested in chemical warfare (CW) agent detection an understanding of the capabilities of the Mine Safety Appliances (MSA) detector tubes to detect chemical warfare vapors. Two MSA types of tubes were evaluated for their ability to detect CW agents at low concentrations: phosphoric acid ester (PAE) tube for nerve agent detection and mustard tube for blister agent detection. The test was designed to characterize the CW agent vapor detection capability of the MSA detector tubes. The agents included Tabun (GA), Sarin (GB), and Mustard (HD). These agents were chosen because of they were believed to be likely terrorist threats. The results showed that the MSA tubes, both phosphoric ester tube for nerve agent detection and the HD tube for mustard detection, were consistent. The phosphoric acid ester tube detected GA and GB at a minimum concentration of approximately 0.01mg/m³. The HD tube detected HD at a minimum concentration of approximately 3 mg/m³. High humidity levels had a significant effect on the HD tubes. The HD tubes failed to detect agent at ambient temperature in 90 percent RH even at a high concentration of 10 mg/m³ HD. Neither MSA tube type performed well in the cold temperature of -5ºC. The PAE nerve agent tubes produced false positives indications on blank runs (absence of CW agent) and the HD tubes showed false negatives. HD tubes also failed to perform well in high moisture conditions. The tubes failed to detect HD at high humidity even at much higher levels than the determined MDL concentration levels. The usefulness in using the HD tubes is questionable because of the vulnerability of HD tubes failure under moderately “moist” conditions. The use of HD tubes in rainy, foggy, or low RH, but higher temperatures conditions will lead to failures. The poor performance of the PAE nerve agent and the HD tubes at “cold” temperatures was also a problem. At -5º, the HD tubes could not detect that HD and PAE nerve agent tubes were producing false positive indications. It seemed that the cooler temperature subdued the chemical reactions required for the tubes proper functioning. The storage and transport temperatures of less than 25ºC could present a problem. As a consequence, users must recognize the limitations of these tubes.