MSA ALTAIR 4XR Operating Manual page 47

Combustible Gas Cross Reference Factors for
General-Purpose Calibration Using Calibration Cylinder (Part No. 10053022)
Combustible Gas
Acetone
Acetylene
Butane
Cyclohexane
Diethylether
Ethane
Ethanol
Ethylene
Gasoline
n-Hexane
Hydrogen
Isobutane
Isopropyl Alcohol
Methane
Methanol
Methyl Ethyl Ketone
Nonane
Nonane with EX-H sensor
Pentane
Propane
Toluene
Xylene
Isobutane
Xylene with EX-H sensor
Response notes
(1) Some compounds may reduce the sensitivity of the combustible gas sensor by poisoning or
inhibiting the catalytic action or by polymerizing on the catalytic surface.
(2) Multiply the displayed % LEL value by the conversion factor above to get the true % LEL.
(3) These conversion factors should be used only if the combustible gas is known.
(4) All factors are based on the IEC 100 % LEL levels
a) i.e. Methane 100% LEL = 4.4 Vol %,
b) Pentane 100% LEL = 1.1 Vol %
c) Propane 100% LEL = 1.7 Vol %
(5) These conversion factors are typical. Individual units may vary by ±25 % from these values.
(6) The results are intended for guidance only. For the most accurate measurements, a device
should be calibrated using the gas under investigation.
Methane Calibration
1.45 Vol % CH
4
Set 33 % LEL
1.09
1.07
1.37
1.94
1.43
1.27
1.16
1.09
1.63
1.86
0.98
1.63
1.55
1.00
0.93
1.69
4.48
3.03
1.90
1.39
1.14
2.09
4.83
3.57
®
ALTAIR 4XR
Technical Data
Pentane Simulant Calibration
1.45 Vol % CH
4
Set 58 % LEL
0.62
0.61
0.79
1.11
0.82
0.73
0.66
0.62
0.93
1.06
0.56
0.93
0.88
0.57
0.53
0.97
2.56
1.73
1.00
0.79
0.93
1.19
2.76
2.04
US
47