Background, Aims and Scope. The development of the international standards for life cycle assessment (ISO 14040:1997, ISO 14041:1999, ISO 14042:2000, ISO 14043:2000) was an important step to consolidate procedures and methods of LCA. Their contribution to the general acceptance of LCA by all stakeholders and by the international community was crucial. Currently, the process of the revision of this first generation of LCA standards is close to completion. The paper explains the Outline as well as formal and technical changes of the coming new international standards of LCA, i.e. the new ISO 14040 and ISO 14044. Methods. The paper refers to life cycle assessment based on the international standards for LCA (ISO 14040:1997, ISO 14041:1999, ISO 14042:2000, ISO 14043:2000). The content relates to the Final Draft International Standard (FDIS) versions of the new ISO 14040 and ISO 14044. Results and Discussion. With the publication of the two new standards, ISO 14040 and ISO 14044, the existing four standards ISO 14040:1997, ISO 14041:1999, ISO 14042:2000 and ISO 14043:2000 are technically revised, cancelled and replaced. According to the scope of the revision, the core part of the technical contents remains unchanged. Improved readability and the removal of errors and inconsistencies was the focus of the revision. However, despite the fact that the main technical content was confirmed to be still valid, some relevant formal and technical changes were made. On the technical side these include e.g. the addition of principles for LCA, the addition of an annex about applications, the addition of several definitions (e.g. product, process, etc.), clarifications concerning LCA intended to be used in comparative assertions intended to be disclosed to the public, clarifications concerning the critical review panel, clarifications concerning system boundary, etc. On the formal side, changes include the reduced number of standards, a reduced number of annexes, a reduced number of pages that contain requirements, alignment of definitions and clarification of compliance with the standards. Conclusion. The two new standards, ISO 14040 and ISO 14044, reconfirm the validity of the main technical content of the previous standards. Errors and inconsistencies were removed and the readability was improved. The added technical content is in line with the previous requirements and serves mainly as a clarification of the technical content. The unanimous vote on the Draft International Standard versions proved that this was achieved on the basis of the broadest possible international consensus. Recommendation and Outlook. Currently the national member bodies undertake the final voting on the FDIS-versions of the standards. Based on the voting results at the previous stages of the documents, a positive result is expected. The publication of the new international standards for life cycle assessment (ISO 14040 and ISO 14044) is expected around mid-2006. For the sake of the international and stakeholder acceptance of LCA, it is recommended that the new standards serve as core reference documents for the users and practitioners of LCA.
