INFICON BCG450 ATM to Ultra-High Vacuum Triple Gauge - Manual (Page 54)

54
tina40e1-b (2011-04)
The gas type dependence in the pressure range 10 -2 … 1 mbar (Pirani sensor
range) can be compensated by means of the following formula:
p
eff
= C × indicated pressure
where Gas type Calibration factor
He 0.8
Ne 1.4
Ar 1.7
Kr 2.4
Xe 3
H
2
0.5
Air, O
2
, CO, N
2
1
CO
2
0.9
Water vapor 0.5
Freon 12 0.7
(The above calibration factors are mean values.)
The gas type dependence in the pressure range <10 -3 mbar can be compensated
by means of the following formula (gauge adjusted for air):
p
eff
= C × indicated pressure
where Gas type Calibration factor C
He 5.9
Ne 4.1
Ar 0.8
Kr 0.5
Xe 0.4
H
2
2.4
Air, O
2
, CO, N
2
1
(The above calibration factors are mean values.)
A mixture of gases and vapors is often involved. In this case, accurate
determination is only possible with a partial-pressure measuring instru-
ment.
Calibration in pressure range
10
-2 … 1 mbar
Calibration in pressure range
<10
-3 mbar