MSA altair 5, Instruction Manual

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5.6 Combustible Gas Cross Reference Factors
General purpose calibration using Calibration Cylinder P/N 10045035
set to 58% LEL Pentane Simulant.
Gas Multiply LEL readings by:
Butane 1.0
Hydrogen 0.5
Methane (ATEX, 4.4% VOL)
0.6
Methane (UL, CSA 5.0% VOL) 0.5
Propane (ATEX, 1.7% VOL) 1.0
Propane (UL, CSA 2.1% VOL) 0.8
Pentane 1.0
Notes:
1. For an instrument calibrated on Pentane, multiply the displayed %LEL value by the
conversion factor above to get the true %LEL.
2. These conversion factors should be used only if the combustible gas is known.
3. These conversion factors are typical. Individual units may vary by +25% from these
values.
4. The results are intended for guidance only. For the most accurate measurements,
an instrument should be calibrated using the gas under investigation.
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