This European Standard specifies the principles and requirements for the determination of GHG emissions from sector-specific sources as of the steel and iron, cement, aluminium, lime and ferroalloy producing industry. This European Standard specifies in particular definitions and rules valid to all above enlisted sector-specific standards, provides common methodological issues and defines the details for applying the rules for the harmonized methods, which include: a) measuring, testing and quantifying methods for greenhouse gas (GHG) emissions of the above mentioned sector-specific sources in the cited standards; b) assessment of the level of GHG emissions performance of production processes over time, at production sites; c) establishment and provision of reliable, accurate and quality information for reporting and verification purposes. The application of this standard to the other sector-specific standards in this series ensures accuracy, precision and reproducibility of the obtained results and is for this reason a normative reference standard, umbrella standard respectively.