Attributional and consequential LCA in the ILCD handbook

PURPOSE: This discussion article aims to highlight two problematic aspects in the International Reference Life Cycle Data System (ILCD) Handbook: its guidance to the choice between attributional and consequential modeling and to the choice between average and marginal data as input to the life cycle inventory (LCI) analysis. METHODS: We analyze the ILCD guidance by comparing different statements in the handbook with each other and with previous research in this area. RESULTS AND DISCUSSION: We find that the ILCD handbook is internally inconsistent when it comes to recommendations on how to choose between attributional and consequential modeling. We also find that the handbook is inconsistent with much of previous research in this matter, and also in the recommendations on how to choose between average and marginal data in the LCI. CONCLUSIONS: Because of the inconsistencies in the ILCD handbook, we recommend that the handbook be revised.