12006 IPCC Guidelines for National Greenhouse Gas InventoriesCH<sub>4</sub> and N<sub>2</sub>O Emissions By Fuel Type and Fuel ConsumedVolume 2, Chapter 3 3.2.1.1`3.2.3`<p><math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Emission</mi></mrow>[/itex] = emission in kg</p> <p><math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Fuel</mi><mi>a</mi></msub></mrow>[/itex] = fuel consumed, (TJ) (as represented by fuel sold)</p> <p><math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>EF</mi><mi>a</mi></msub></mrow>[/itex] = emission factor (kg/TJ)</p> <p><math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>a</mi></mrow>[/itex] = fuel type a (e.g., diesel, gasoline, natural gas, LPG)</p>This is the equation for the Tier 1 method for estimating CH4 and N2O from road vehicles. It implies the following steps: ? Step 1: Determine the amount of fuel consumed by fuel type for road transportation using national data or, as an alternative, IEA or UN international data sources (all values should be reported in terajoules). ? Step 2: For each fuel type, multiply the amount of fuel consumed by the appropriate CH4 and N2O default emission factors. Default emission factors may be found in the next Section 3.2.1.2 (Emission Factors). ? Step 3: Emissions of each pollutant are summed across all fuel types.100http://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html