GASTEC CORPORATION - For all types of gas and vapour

Detector tubes

Detector tubes


What if a gas detector tube does not change any colours after sampling?


Confirm that the front cap of GV-100 sampling pump is firmly tightened. After confirming that the pump handle is fully in, insert unbroken tube into the rubber inlet of the pump and perform an air leak test on the pump to ensure a vacuum is created.  Ensure that the gas detector tubes are kept in a cool place or in a refrigerator.


What if a gas detector tube changed unknown colours?


Other gases or vapours may be interfering with the chemical reagents inside the tube.  Please refer to the instruction manual or hand book.


How long do tubes last?


Gas detector tubes are guaranteed for the shelf life. Please check the shelf life dates on the tube package.


If I perform a gas measurement with a gas-detecting tube under pressure, will there be a considerable effect on the tube reading?


Generally the gas concentration is proportional to the pressure. All detector tubes are calibrated based on normal atmospheric pressure (1013 hPa or 760 mmHg) and their indications will not be affected over the range of plus-minus 10% of normal pressure, that is 912 to 1114 hPa or 684 to 836 mmHg. If the pressure at the time of measurement is not in this range, the tube reading should be corrected as follows.

True concentration
= Tube reading X 1013 (hPa) / Atmospheric pressure (hPa)
= Tube reading X 760 (mmHg) / Atmospheric pressure (mmHg)


I can not find the gas or vapour name I am looking for in your tube list or in your Hand Book, what should I do?


If there are no gas names on the list or hand book, contact us or our local representatives with the gas specifications and conditions. GASTEC will respond immediately.


Can I use an expired detector tube?


No, the expiration date is a period which we guarantee the accuracy of detector tubes.


Can I store detector tubes in the freezer?


Even if the tubes are instructed to be stored in the refrigerator, please do not freeze the tubes.


Do GASTEC tubes fit any piston type pump?


No! Use only GASTEC tubes in a GASTEC pump. Do not interchange or use non-GASTEC parts or components in GASTEC’s tube and pump system.


Is an Oxygen Tube heated up right after sampling?


Yes, Oxygen tube will get hot. Do not touch the oxygen tube (31B and 31E) with bare hands after measuring, as the tube is heated up by the reaction heat. The tube temperature will go down within 2-3 minutes after sampling (measuring).


Do I need a temperature correction?


Yes. Some tube needs a temperature correction, refer to your instruction manuals and correct your tube reading by using a correction chart.