Gas detection tubes operate in the following manner: An air sample is drawn through a tube containing a reagent, causing a color change. The concentration is then read from the length of the color stain in the reagent. The advantages of detection tubes over other analytical methods are simplicity of use, rapid response, low cost, and very low maintenance. Detection tubes is pre-calibrated, no calibration equipment is necessary. Errors are prevented by directly marking the calibration information on each tube, and accuracy is further ensured by controlling the volume of air sampled.
ANH VU gas detection supply Gas detection tube by Honeywell RAE systems USA, Gastec tube from Japan and Draeger tube from Germany.