This International Standard specifies requirements and provides guidelines for life cycle assessment (LCA) including a) the goal and scope definition of the LCA, b) the life cycle inventory analysis (LCI) phase, c) the life cycle impact assessment (LCIA) phase, d) the life cycle interpretation phase, e) reporting and critical review of the LCA, f) limitations of the LCA, g) relationship between the LCA phases, and h) conditions for use of value choices and optional elements.