A gas detector tube is a measurement device used to detect and estimate the concentration of a specific gas or vapour in air. Detector tubes are widely used for industrial hygiene, workplace monitoring, environmental measurement and field gas testing.
GASTEC offers a broad range of detector tubes designed for measuring over 500 different gases and vapours with extreme precision and simplicity.
“Detector tubes offer a direct-reading, calibrated colorimetric measurement that requires no on-site electrical power, making them ideal for spot-testing and harsh hazardous environments.”
How Does a Gas Detector Tube Work?
A detector tube contains a chemical reagent designed to react with a particular gas.
During sampling, air is drawn through the tube using a compatible sampling pump (such as the GASTEC GV-100S or GV-110S). When the target gas comes into contact with the reagent, a visible colour change occurs.
The resulting colour-change indication can then be compared with the calibrated scale printed directly on the glass tube to determine the concentration immediately.
This provides a practical, reliable method of direct-reading gas measurement in the field.
How Are Gas Detector Tubes Used?
Although the exact procedure depends on the tube and equipment, a typical process includes:
1. Select the Correct Tube
Choose a detector tube designed for the gas you need to measure and the expected concentration range.
2. Prepare the Sampling Pump
Use the compatible sampling pump according to the manufacturer's instructions.
3. Prepare the Detector Tube
Break both ends of the hermetically sealed glass tube using the tip cutter.
4. Collect the Air Sample
The pump draws a defined volume (e.g., 50ml or 100ml) of air through the detector tube.
5. Observe the Reaction
The reagent changes colour as it reacts specifically with the target gas molecules.
6. Read the Measurement
The length of the colour-change indication corresponds directly to the concentration on the scale.
7. Record the Result
The result should be documented according to the applicable workplace safety protocol.
What Gases Can Detector Tubes Measure?
Depending on the tube selected, detector tube systems can be used for a wide range of gases and vapours. Examples include:
The available measurement range and operating procedure depend on the individual detector tube model.
Where Are Gas Detector Tubes Used?
Oil & Gas
Gas detector tubes can support specific gas measurement during inspection and maintenance.
Wastewater
H₂S measurement can be relevant around wastewater plants, sewage systems and manholes.
Marine
Detector tubes can support atmospheric measurements in ballast tanks and enclosed areas.
Chemical Processing & Hygiene
Specific tubes can be selected for workplace exposure assessment and process emissions.
Gas Detector Tubes vs Electronic Gas Detectors
Gas detector tubes and electronic detectors use different measurement technologies. Detector tubes use a chemical reaction and are generally designed for specific spot measurement. Electronic detectors use sensors and provide digital readings and continuous alarms.
Read our comparison article: GASTEC Gas Detector Tubes vs Electronic Gas Detectors: Which Should You Use?
Why Choose GASTEC Detector Tubes?
GASTEC provides an extensive range of direct-reading gas detector tubes and compatible sampling equipment. This allows users to select tubes based on the exact gas, concentration range, and measurement requirements of their application.
Conclusion
Gas detector tubes provide a portable, reliable method of measuring specific gases and vapours. When the correct tube and sampling equipment are selected and used according to the manufacturer's instructions, they can support a wide range of industrial measurement applications.
Al Ghwasa supplies genuine GASTEC gas detector tubes and gas sampling equipment for customers across the UAE, GCC and international markets.
Frequently Asked Questions
Looking for the right GASTEC detector tube?
Contact Al Ghwasa for comprehensive product guidance and rapid regional supply.