Drager Test gas ampoule SO2 50 ppm
Every Draeger Tube is a glass vial that is filled with a chemical reagent, that will react with a specific chemical or type of chemical family. When you snip the ends of the tube, put one end into a Draeger-Tube pump, and draw air through the Draeger tube, if the gas is present in the surrounding environment the tube will change colors measuring the concentration present.