Gas Colour Change Tubes and Colorimetric Tubes

Gas detection tubes are small glass tubes that contain chemical that will react specifically with a target gas, once placed onto a hand operated hand pump you draw a sample of air through the tube and if there is any target gas in the air it will react with the chemical in the tube causing a colour change which can be read to give you your concentration of gas.

This method can be used on a wide variety of gas BUT it is only a spot check of the concentration thus if there is a sudden change you will not detect it. This method is not always appropriate, especially for personal exposure monitoring where a Gas Detector would be more appropriate.