ISO 14044 requires the goal and scope of an LCA to be clearly defined and be consistent with the intended application. Due to the iterative nature of LCAs, it is possible that the LCA scope needs to be refined during the study.

The goals and scopes of the methodologies correspond to either approach a) or b), given below, that ISO 14040:2006, Annex A2 gives as two possible approaches to LCAs.

a) An approach that assigns elementary flows and potential environmental impacts to a specific product system, typically as an account of the history of the product. See Section 4.1.2.

b) An approach that studies the environmental consequences of possible (future) changes between alternative product systems. See Section 4.1.3.




In this document, approach (a) is referred to as an attributional approach, while approach (b) is referred to as a consequential approach. Complementary information is accessible in the ILCD handbook[1].




A Carbon Footprint of a Product (3.1.2) or Partial Carbon Footprint of a Product (3.1.3) as defined by ISO 14067 may be estimated using either the attributional or the consequential approach, the latter corresponding to the use of “system expansion via substitution” to avoid allocation when a unit process yields multiple co-products.




This document applies to the CFP for hydrogen production. There are numerous pathways to produce hydrogen. This document describes in the annexes the requirements and evaluation methods applied to several hydrogen production pathways of interest. This document considers the GHG emissions associated with hydrogen production up to the production gate.




This document applies to and includes every steps within the production process up to the production gate (see Figure 2 in the Introduction). Complementary documents in the ISO 19870-X series will consider hydrogen conditioning, conversion and transport methods.