Generating Calibration gas with a
permeation tube
Product List of Calibration gas generating equipment Gastec
A permeation
tube is a fluororesin tube that contains high-grade liquefied gas. When the
tube is exposed to a certain temperature, liquefied gas penetrates the tube wall
by osmosis in time-increments enabling a specific quantity of gas to be
retained in the tube . Consequently, a carrier gas flowing at a constant speed
(for calibration purposes) can be continuously generated by keeping the tube at
a fixed temperature and infusing a constant quantity of dilution gas. This
method is highly reliable because the concentration of the calibration gas is
determined by calculating the decrease in weight of the permeation tube and the
quantity of dilution gas. This dynamic method also enables highly reactive
gases such as chlorine, hydrogen sulphide or ammonia to be generated. As shown
in the table below, there are many different kinds of permeation tubes and they
are widely used because they can provide a stable supply of calibration gas.
Product List of Calibration gas generating equipment Gastec
|
Calibration gas name
|
P-tube catalog No
|
Concentration range (ppm)
|
|
acetaldehyde
|
P-92-1
|
0.1-5.2
|
|
ammonia
|
P-3
|
0.2-17.9
|
|
P-3-M
|
0.3-40.8
|
|
|
ethyl mercaptan
|
P-72-H
|
0.04-1.87
|
|
ethylene oxide
|
P-163-H
|
0.5-23
|
|
Formaldehyde
|
P-91-H-5
|
0.0049｡ﾁ0.24
|
|
vinyl chloride
|
P-130-H
|
0.3-13.8
|
|
vinyl chloride
|
P-131
|
0.05-3.7
|
|
P-131-H
|
0.8-58
|
|
|
methyl chloride
|
P-132-H
|
1.6-77
|
|
chlorine
|
P-8-1
|
0.03-3.3
|
|
P-8-5
|
0.15-16.4
|
|
|
P-8-M
|
0.5-53.1
|
|
|
methylene chloride
|
P-138-H
|
0.3-15.8
|
|
dimethylamine
|
P-181-H
|
0.2-10.3
|
|
methyl bromide
|
P-136-H
|
0.5-23
|
|
bromine
|
P-10-H
|
0.016-2.52
|
|
trimethylamine
|
P-180-H
|
0.06-3.1
|
|
Styrene
|
P-124-H
|
0.0045-0.22
|
|
sulphur dioxide
|
P-5-5
|
0.04-3.6
|
|
P-5
|
0.1-7.2
|
|
|
P-5-H
|
1.1-76.4
|
|
|
nitrogen dioxide
|
P-9-1
|
0.05-3.99
|
|
P-9-H
|
1.8-133
|
|
|
dimethyl sulphide
|
P-73-H
|
0.003-0.45
|
|
1, 3-butadiene
|
P-174-H
|
0.7-31
|
|
hydrogen fluoride
|
P-17
|
0.11-11.3
|
|
P-17-5
|
0.3-29
|
|
|
P-17-H
|
0.6-58
|
|
|
propane
|
P-100
|
0.03-1.9
|
|
propylene oxide
|
P-164-H
|
0.7-33
|
|
chlorofluocarbon 11
|
P-51-H
|
0.4-16.4
|
|
methylamine
|
P-182-H
|
0.5-25.6
|
|
methyl mercaptan
|
P-71-5
|
0.007-1.52
|
|
P-71-H
|
0.16-11.4
|
|
|
dimethyl sulphide
|
P-74-H
|
0.04-6.3
|
|
hydrogen sulphide
|
P-4
|
0.1-13.6
|