Colorimetric tubes are best described as which of the following?

• A. Gas-Specific, Used to Test for Gases in Hazardous Spills
• B. Infrared Gas Detectors
• C. Gas Chromatography Units
• D. Mass Spectrometers

Answer: (A)

Colorimetric tubes are field-testing tools designed for quick, gas-specific screening. They contain reagents that react with a targeted gas, producing a visible color change when air is drawn through the tube with a pump. The length or intensity of the colored band correlates with the gas concentration and is read against a calibration scale, giving an immediate, approximate readout of the presence and level of that specific gas. This makes them ideal for assessing hazardous spills on scene where rapid, on-site decisions are needed and you’re testing for particular gases.

They are not infrared gas detectors, which rely on infrared light absorption for continuous monitoring; nor are they gas chromatography units, which separate and identify multiple components in a sample; nor mass spectrometers, which analyze molecular masses with highly detailed, lab-grade instrumentation.