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AP-42

2 posts on AP-42.

Natural Gas BTU: What Wellhead Gas Actually Measures

Pipeline gas runs near 1,020 Btu per cubic foot. Wellhead gas runs higher. Measured heating values across eight states, and which calculations they change.

AERMOD Emission Rates: Where the Numbers Come From

AERMOD takes an emission rate as an input and never calculates it. Where that number comes from, what AP-42 factors assume, and when it matters.