ThermoFisher Scientific 146iQ, Instruction Manual

Page: 280 / 302

Optional Equipment
Permeation Oven
9-20 146iQ Instruction Manual Thermo Scientific
Figure 9–12. Installing glass tube pt 4
The computation of gas output level is shown in the following information.
Note that is assumed that all devices are properly calibrated and that all
flows are corrected to 25 °C and 1 atm.
Permeation Tube:
Q
(K) (R)
= (ppm) Output
o
Where:
R = permeation rate in ng/min
Q
0
= flow rate of gas (scc/min) into the charcoal scrubber during span mode
K = constant for the specific permeant = 24.45 / MW
MW = molecular weight
Computation of
Concentrations