Method 19
Determination of Sulfur Dioxide Removal Efficiency and Particulate Matter, Sulfur Dioxide, and Nitrogen Oxide Emission Rates
40 CFR Part 60, Appendix A-7
From the method — regulatory text
Sections 1.0 and 2.0 of Method 19—Determination of Sulfur Dioxide Removal Efficiency and Particulate Matter, Sulfur Dioxide, and Nitrogen Oxide Emission Rates, as published at 40 CFR Part 60, Appendix A-7. Retrieved 10/07/2026. The full method is on the eCFR.
1.0 Scope and Application
1.1 Analytes. This method provides data reduction procedures relating to the following pollutants, but does not include any sample collection or analysis procedures.
| Analyte | CAS No. | Sensitivity |
|---|---|---|
| Nitrogen oxides (NOX), including: | ||
| Nitric oxide (NO) | 10102-43-9 | N/A |
| Nitrogen dioxide (NO2) | 10102-44-0 | |
| Particulate matter (PM) | None assigned | N/A |
| Sulfur dioxide (SO2) | 7499-09-05 | N/A |
1.2 Applicability. Where specified by an applicable subpart of the regulations, this method is applicable for the determination of (a) PM, SO2, and NOX emission rates; (b) sulfur removal efficiencies of fuel pretreatment and SO2 control devices; and (c) overall reduction of potential SO2 emissions.
2.0 Summary of Method
2.1 Emission Rates. Oxygen (O2) or carbon dioxide (CO2) concentrations and appropriate F factors (ratios of combustion gas volumes to heat inputs) are used to calculate pollutant emission rates from pollutant concentrations.
2.2 Sulfur Reduction Efficiency and SO2 Removal Efficiency. An overall SO2 emission reduction efficiency is computed from the efficiency of fuel pretreatment systems, where applicable, and the efficiency of SO2 control devices.
2.2.1 The sulfur removal efficiency of a fuel pretreatment system is determined by fuel sampling and analysis of the sulfur and heat contents of the fuel before and after the pretreatment system.
2.2.2 The SO2 removal efficiency of a control device is determined by measuring the SO2 rates before and after the control device.
2.2.2.1 The inlet rates to SO2 control systems (or, when SO2 control systems are not used, SO2 emission rates to the atmosphere) are determined by fuel sampling and analysis.
EssentialRegs notes
Our plain-English reading of Method 19. Not the method text.
What it measures
Emission rates of sulfur dioxide, nitrogen oxides and particulate matter, expressed per unit of heat input, and the sulfur dioxide removal efficiency of a control system or fuel treatment.
How it works
Method 19 is a calculation method, not a sampling method. It takes pollutant concentrations measured by other methods and converts them to an emission rate using an F-factor, a fuel-specific ratio of the volume of combustion gas produced to the heat released by burning the fuel. The F-factor is applied with an oxygen or carbon dioxide measurement from the same gas, which removes the need to measure the total gas flow. The method supplies F-factors for common fuels and shows how to derive one from a fuel analysis.
Equipment
None of its own. It uses concentration data from other test methods, oxygen or carbon dioxide data, and fuel sampling and analysis results.
When a rule cites it
Rules that set an emission limit per unit of heat input and let the operator calculate the rate from fuel data and gas concentrations instead of measuring stack flow. It is also cited for determining sulfur dioxide removal efficiency across a control system.
Notes for compliance staff
Method 19 is only as good as the concentration and oxygen data fed into it, so a report that cites it should also cite the methods that produced those inputs. It applies to fuel-burning equipment because the F-factor depends on the fuel.
Cited by
Provisions in the corpus whose text cites Method 19. Subscribers land on the provision in the regulation reader; visitors see a preview of it (the GP05 sample opens in full).
Regulation 7
Regulation 26
40 CFR Part 60 Subpart IIII
40 CFR Part 60 Subpart JJJJ
- Table 2 to Subpart JJJJ of Part 60 — Requirements for Performance Tests
40 CFR Part 63 Subpart ZZZZ
The sections marked as regulatory text above are reproduced from the CFR. Everything under ‘EssentialRegs notes’ is our reference copy, not the method. The method as published in the CFR controls.