HANDBOOK OF UNCERTAINTY CALCULATIONS -Fiscal Orifice Gas and Turbine Oil Metering Stations
Norwegian regulations relating to measurement of petroleum for fiscal purposes and for calculation of CO2 tax require that the overall measurement uncertainty be documented to be within defined limits. However, the different methods used gave different results. A consistent, standardised method of uncertainty estimation was required, so that different measurement systems could be directly compared.
In 1992 the Guide to the expression of uncertainty in measurement was published, revised and updated in 1995. This report is establishing general rules for evaluating and expressing uncertainty in measurement, intended for a broad scope of measurement areas. It is commonly referred to as ”the Guide”. The report was jointly developed by the International Organisation of Standardisation (ISO), the International Electrotechnical Commission (IEC), the International Organisation of Legal Metrology (OIML) and the International Bureau of weights and Measurement (BIPM).