ForewordIntroductionScopeNormative referencesTerms and definitionsSymbolsSymbolsSubscriptsCalculation of uncertaintyGeneral considerationsPrinciplesStep 9 — Calculation of uncertainty of mole fractionsDetermining the equations to be usedGeneral considerationsStage 1Stage 2Stage 3Calculation of uncertainty of component mole fractions — Mean normalization methodGeneral considerationsUncertainty of raw mole fractionsUncertainty of normalized mole fractionInput dataCalculation of uncertainty of component mole fractions — Run-by-run normalization methodGeneral considerationsUncertainty of raw mole fractionUncertainty of normalized mole fractionAdditional input dataStep 10 — Calculation of the expanded uncertainty of mole fractionsCalculation of processed component uncertainties for the methane-by-difference approach (informative)General considerationsCalculation of methane-by-difference component uncertaintiesUncertainties of relative response factors (normative)Uncertainties of relative response factors for flame ionization detectors (FIDs)Uncertainties of relative response factors for thermal conductivity detectors (TCDs)Alternative calculation of the uncertainty of the value of the unknown (informative)Bibliography