Disposable Permeation Tubes are tubular devices about the size of a pencil with liquid component compound sealed inside. The component compound slowly permeates through the tubing wall creating a very small flow of component vapor. Disposable tubes have a finite operating life and are discarded at the end of that life. They are primarily used to make lower and medium concentration mixtures. Disposable Permeation Tubes are popular because they are small and convenient to use.
KIN-TEK Trace Source™ Disposable Permeation Tube Brochure
The purpose of a gas standard is to establish accurate reference points for the verification of an analysis. Static mixtures in gas cylinders are often unreliable and inaccurate at the levels (ppm to ppb) that analytical technology now demands. In gas cylinders containing low level mixtures, the trace components often adsorb on to, or react with, the cylinder walls causing the standard to be inaccurate and unreliable. Also, it may be impossible to get a matrix gas that is completely free of the trace component, thus making it impossible to get a true reference point with a cylinder mixture. These problems are solved by using permeation tubes in lieu of gas cylinders.
SRT Standard Rate Disposable Permeation Tubes
- SRT Standard Rate Disposable Permeation Tubes generate moderate concentrations of high vapor pressure compounds. These compounds include SO2, H2S, NH3, Cl2, etc. Additionally, SRT permeation tubes can generate very low concentrations of low vapor pressure compounds such as Carbon disulfide, Methylene chloride and Nitric acid. Typical emission rates yield concentrations of 1 to 10 ppm depending on the compound, operating temperature and dilution flow rate.
SRT-2 Standard Rate Disposable Permeation Tubes
- SRT-2 Disposable Permeation Tubes can generate moderate concentrations of high vapor pressure compounds such as Cl2, NO2 and NH3. These tubes can be used at temperatures up to 50°C. Typical emission rates yield concentrations of sub-ppm to 5 ppm depending on the compound, operating temperature and dilution flow rate.
HRT High Rate Disposable Permeation Tubes
- HRT Permeation Tubes can generate moderate concentrations of low vapor pressure compounds. These compounds include C2H5SH, CCl4, Acrylonitrile, Benzene, Styrene and Water. HRT tubes are also used for generating high concentrations of SO2, CH3SH and other moderate vapor pressure compounds. Typical emission rates yield concentrations of 1 to 20 ppm, depending on the compound, operating temperature and dilution flow rate.
Extra Life Disposable Permeation Tubes
Extra life (EL) Permeation Tubes are designed to have a longer operating life than other disposable tubes and are recommended for special compounds.
ELHRT Extra Life High Rate Disposable Permeation Tubes
- EL-HRT Permeation Tubes are used for generating moderate concentrations of low vapor pressure compounds such as C2H5SH, Benzene, and Water, and for generating high concentration mixtures of SO2, CH3SH and other moderate vapor pressure compounds. Typical emission rates yield concentrations of 1 to 10 ppm, depending on the compound, operating temperature and dilution flow rate.
ELSRT Extra Life Standard Rate Disposable Permeation Tubes
- EL-SRT Permeation Tubes are used for generating moderate concentrations of high vapor pressure compounds such as SO2, H2, NH3, and Cl2, and for generating very low concentrations of low vapor pressure compounds such as Benzene, Acrolein, and Water. Typical emission rates yield concentrations of 1 to 5 ppm, depending on the compound, operating temperature and dilution flow rate.
ELSRT-2 Extra Life Standard Rate Disposable Permeation Tubes
- ELSRT-2 Permeation Tubes are used for generating low to moderate concentrations of high vapor pressure compounds such as Cl2, NO2, and NH3. Typical emission rates yield concentrations of sub-ppm to 2.5 ppm, depending on the compound, operating temperature and dilution flow rate. This type of tube is also used for field service where higher operating temperatures may be required.
To learn more, read the following PDF document titled Permeation Tubes: A simple Path to Very Complex Gas Mixtures.
