This document provides guidance for calculating the CO2 intensity at steel plants with all types of process routes, by defining the boundary, CO2 emission factors and the intermediate products for which upstream emissions are considered for all types of process routes. In particular, this document provides guidance applicable to the ISO 14404 series to the types of steel plants listed below. This document also includes the Universal Calculation Sheet, which covers all relevant emission sources from ISO 14404-1, ISO 14404-2 and ISO 14404-3 to assist the calculation of CO2 emissions.i. Steel plants with different process routes from ISO 14404-1, ISO 14404-2 and ISO 14404-3 (7.2.1)ii. Steel plants with more than one process route (7.2.2)iii. Steel plants purchasing pig iron from the outside (7.2.3)iv. Steel plants and rerollers purchasing part or all of crude steel from outside (7.2.4)Moreover, this document provides additional guidance to the entire ISO 14404 series for the following topics.a) Evaluation of exported slagsb) Evaluation of by-product gasc) Evaluation of stockd) Selection of calorific values and emission factors for electricity and fuelConversion to energy consumption and to consumption efficiency can be obtained using Annex A.While the use of the calculation result is outside the scope of this document, appropriate applications and inappropriate application are recommended in Annex B.