8
Oxygen Calibration Table
The Effects of Pressurizing the Sensor
Oxygen sensors usually do not measure the
percentage of oxygen in a mixture of gas but they
measure the partial pressure of oxygen. This is why
Weld Gas Analyzers can sometimes give erratic
readings when exposed to too high gas flow or strong
winds which cause the sensor to be pressurized.
Feet
(above sea level)
Meters
(above sea level)
Calibrate Sensor To
0
0
20.90
1,000
305
20.20
2,000
610
19.40
3,000
915
18.70
4,000
1,220
18.10
5,000
1,525
17.40
6,000
1,830
16.80
8,000
2,440
15.50
10,000
3,050
14.40
12,000
3,660
13.30
The Effects of Altitude on the Sensor
The partial pressure of oxygen in air is 0.209 bar (20.9
%) at sea level. In higher altitudes the air becomes
thinner and the partial pressure of oxygen in the air
changes. The calibration figure of 20.90 in air can be
adapted to the altitude to ensure optimum accuracy.
Please see table below for more information.
