FAQs

Frequently Asked Questions

What is a gas detection tube?

Colorimetric gas detector tubes are glass tubes filled with chemical reagents that absorb and react to the measured targeted gas or vapour. A colorimetric stain (colour change) appears. The reading of the concentration is made directly on the scale printed on the tube for almost any gas detection tube. This gas detection tube system is composed of an air sampling pump and a detector tube.

What is the operating principle?

Colorimetric and dosimeter gas detection tubes are usually sold in ten unit boxes and are sealed at both ends. During the operation, the ends of the tubes are broken using the built-in tip breaker of the manual sampling pump. Gas detector tubes are designed for use with a portable air-sampling pump. Depending on the manufacturer, these pumps operate through a piston or a bellows system. The tube is connected to the pump and the user samples 50 to 100mL of ambient air.

Then the sample goes through the gas detection tube and reacts with the chemical reagent. The size of the created stain is proportional to the concentration. The concentration can be instantly read using the scale printed on the tube without the help of a laboratory. The stopping point of a chemical reaction is easily read thanks to the lines printed on the tube.

What are the different measuring ranges?

Several measuring ranges are available for numerous gases and vapours (ppm, %, mg/m3, mg/L). This gives the opportunity to measure low and high concentrations with the same accuracy.

What if I get a blurred result after a test?

The discoloration of the reagent can sometimes be blurred on a gas detection tube. If so, take the average between the two ends of the blurred part.

How can I store and dispose gas detection tubes?

It is recommended to store detection tubes in a cool (from 0 to 10°C) and dark place to preserve their quality. Any direct contact to sunlight could damage the reagent of the tubes. Always store them in a safe place and keep them away from children.

As gas detection tubes are filled with sensitive reagents that can be corrosive, they need to be stored and handled safely and carefully.

Can I use tubes even when they expired?

No, using an expired gas detection tube can provide false readings. We strongly advise against using expired tubes.

What is the shelf life of the detector tubes ?

Most of gas detector tubes have a lifetime of 1 to 3 years depending to the reagent and if stored in a cool and dark place. The expiration date is clearly marked on the gas detection tube packaging.