Heath Consultants Odorator Propane - Manual (Page 25)

Appendix C
Therefore the actual value will be 60% of the difference in the chart higher
actual from the chart lower actual. Again, the lower value will be the base
or reference.
60% of (.18 - .15) = .6 x .03 = .018 which is rounded off to .02
Since the actual value base is .15, the actual value will be .15 + .02 = .17% gas.
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