Calculators
Emissions Estimation (AP-42)
Annual criteria pollutant and CO2 emissions from fired equipment (heaters and boilers) using EPA AP-42 emission factors.
Method: Annual emissions (tons/year) = EF (lb/MMBTU) · Q (MMBTU/hr) · hrs ÷ 2000. CO2e in metric tons applies the 0.907185 short-ton conversion. Source: EPA AP-42 Compilation of Air Pollutant Emissions Factors, Chapter 1.4 (Natural Gas Combustion) and Chapter 1.3 (Fuel Oil Combustion). Use site-specific source test data if available — AP-42 factors are uncontrolled averages and may not reflect low-NOx burners, SCR, or BACT limits.
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© 2026 Inflection Point Engineering, LLC. All rights reserved.