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Any source with an activity-based factor

AP-42 Calculator

General activity-based calculation for any source category with a published per-unit emission factor.

Input assumptions

Activity data
units/hr

In the same unit as the factor's denominator (e.g. tons/hr, MMscf/hr, 1,000 gal/hr).

hr/yr

8,760 hr/yr for potential to emit unless an enforceable limit applies.

%

Only claim control you can document and enforce.

Emission factor

Take the factor from the AP-42 chapter and section for your source category. Record the section number, table, revision date, and factor rating.

lb/unit

Calculation result

Enter activity rate, emission factor to see results, or fill demo values to explore.

Calculation methodology

Activity-based method. Multiplies an hourly activity rate (fuel burned, material processed, product made) by an emission factor expressed per unit of that activity. Units must match: the factor's denominator must be the activity unit.

E (lb/hr) = A (units/hr) × EF (lb/unit)
Emission factor
Emission factor: — lb/unit
Source / reference
Not provided. Results without a cited factor are not defensible.

Calculation set

Add several sources or pollutants and total them. Stored in this browser tab only until accounts launch.

No calculations added yet.

Native Excel and PDF exports with full methodology arrive with saved accounts. Phase 2

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