Teledyne 9700 instruction manual Response of Combustible Sensor to Various Gases

Flue Gas Analysis System Appendix

Response of Combustible Sensor to Various Gases

Response factors have been determined to relate the sensor output of a specific compound to the output obtained using methane. A list of some typical compounds is given in Table 1 along with their LEL (Lower Expo- sure Limits) values. To determine the output of the sensor for any of the gases listed, compared to the same concentration of methane, multiply the reading obtained by the factor listed. For example, if the output is cali- brated with methane at 2%, the output for ethylene at 2% would be 2.0% X 1.26 = 2.52% methane equivalent.

TABLE 1: Detector Response To Various Gases

COMPOUND	LEL*	RESPONSE FACTOR
Methane	5.0	1.00
Hydrogen	4.0	0.86
Carbon Monoxide	12.5	0.32
Ethane	3.0	1.20
Ethylene	2.7	1.26
Acetylene	0.5	1.39
Propane	2.2	1.42
Propylene	2.0	1.33
Butane	1.9	1.54
Hexane	1.1	1.50
Cyclohexane	1.3	1.44
Heptane	1.05	1.59
Benzene	1.3	1.50
Pentane	1.5	1.45
Toluene	1.2	1.48
Ethylene oxide	3.6	0.76
Methyl Ethyl	1.8	0.96
Ketone
Methyl Acrylate	2.8	0.59

*Taken from Fire Hazard Properties of Flammable Liquids, Gases and Volatile Solids, National Fire Protection Agency.

NOTE: For compounds not listed in Table 1, consult the factory.

TELEDYNE BROWN ENGINEERING A-5

Analytical Instruments