The Uniphos Gas Detector Tube Handbook is a handy reference, packed with all the information about our Uniphos gas detector tubes.
Our handbook provides details on target gases, interfering gases and cross sensitivities. We currently have over 200 different tubes including short-term and long-term tubes.
The short-term detector tube system consists of Uniphos Detector Tube and Uniphos Precision Air Sampling Pump (ASP-40). Together they form a short-term detector tube measurement system. Short-term detector tubes measure the gas concentration existing at the point of measurement at that instant of time.
Uniphos detector tubes are glass tubes with a length of 150 mm and outside diameter of 5 mm which are filled with an inert carrier material impregnated with an indicator to produce a colorimetric reaction, the tubes are hermetically sealed at the factory. They show color change when the sample air is drawn through it after breaking both the ends of the tube. A piston and barrel type pump (Uniphos Precision Air Sampling Pump) is used to draw the sample air through the tube. They are pre-calibrated using gas standards. The printed calibration scale enables the user to know the target gas concentration directly after the sampling.
Our long-term tubes come in two forms: Dosimeter tubes or Time Weighted Average (TWA) tubes which produce a color change as the gas molecules diffuse into the tube and charcoal tubes which are used with a constant flow pump to collect the vapor molecules of organic compounds.
While the short-term detector tubes give the instantaneous concentration of target gas at the time of measurement, Dosimeter tubes or Time Weighted Average (TWA) tubes give a stain length, which is proportional to the concentration over the time of exposure.
The charcoal tube is a glass tube filed with two layers of activated coconut shell charcoal and sealed at both ends. One of the layers is an active layer (sorbent layer) and the second one is the breakthrough layer. It is used for determining organic vapors like benzene, toluene xylene etc. in the atmosphere. Charcoal tubes are analyzed in a laboratory using various analytical methods.
Our detailed handbook outlines procedures for using both types of tubes, as well as dealing with storage and disposal. The handbook also explains calibration gas generation methods and gas concentration units and their conversions.