Highlights
– GLAM is the Global Life Cycle Impact Assessment (LCIA) Method developed within the Life Cycle Initiative, hosted at UNEP.
– Characterizes impacts on ecosystem quality, human health, and socio-economic assets.
– 1 million LCIA Characterization Factors (CFs), covering the effects of 14,000 Life Cycle Inventory flows on 22 impacts categories.
– GLAM consensus-based global LCIA method is potentially applicable to millions of products and services
Building on the consensus-building work on life cycle impact assessment since its launch in 2002, the Life Cycle Initiative started GLAM in 2013. The work has been co-led by the University of Michigan, Norwegian University of Science and Technology (NTNU) and Denmark’s Technical University (DTU) and has benefited from the collaboration of hundreds of scientists from across the world. The overall goal of GLAM was to establish a comprehensive, consistent, and global Environmental Life Cycle Impact Assessment Method, covering classification, characterization, normalization, and weighting to assess the life-cycle impacts of products and services on human health, ecosystem quality, and natural resources. The results of this 11-year project were launched in October 2024 as GLAM 1.0.2024.10.
GLAM is funded by the Life Cycle Initiative funding partners, specific contributions from the Swiss, French, and German Governments, and is supported by the in-kind contribution from more than 200 scientists.
The GLAM Methodology
GLAM addresses impacts on three areas of protection (AoPs ) – ecosystem quality, human health, and socio-economic assets (natural resources, ecosystem services) – through a standardized method. It incorporates a consistent approach to classification, normalization, and weighting, enabling comparisons across regions. This integration ensures a cohesive understanding of environmental impacts, from biodiversity and climate effects to air pollution and resource valuation.
The impact categories included in the GLAM methodology are clustered into the AoPs as follows:
- Ecosystem quality
- Represents potential damage on biodiversity, focusing on species vulnerability and harmonizing previous recommendations related to land and water use, freshwater ecotoxicity, freshwater and marine eutrophication, microplastics in marine ecosystems, terrestrial acidification and climate change on freshwater, terrestrial and marine ecosystems.
- Human health
- Represents potential damage on human population lifetime loss, focusing on climate change, fine particulate matter impacts, toxicity, work environment impacts, lifestyle impacts including nutrition and physical activity, ionising radiation, and water scarcity.
- Socio-economic assets
- Evaluates the values of natural resources and ecosystem services from land use for human well-being.
The methodology includes characterization factors specific to each impact category at both midpoint and damage levels, to compare scenarios within each category, as traditionally done in midpoint-oriented methods. At damage level, these impacts can then be further compared and/or aggregated into total damages for each Area of Protection. Normalization and weighting factors then enable practitioners to compare impact scores across AoPs. From a technical standpoint, GLAM developed and applied calculation framework to get a global normalization inventory for all impact categories and deterministic weights for each area of protection. It also ensures consistent LCI-LCIA linkage in collaboration with the global nomenclature system developed in GLAD to facilitate the implementation of the GLAM LCIA method in LCA software.
A consensus-based Methodology
Over the years, GLAM worked with a balanced mix of participants; international experts from five topical tracks: LCIA method developers, providers of LCA studies (primarily consultants and industry associations), and users of life cycle information, including governments and intergovernmental organizations, industry, NGOs, and academics.
Building on the LCIA framework established in the early 2000s within SETAC and the Life Cycle Initiative, two consensus workshops held in 2016 and 2018 provided guidance, recommendations and characterization factors for multiple individual impact categories.
A new consensus process was initiated in 2019, to develop GLAM as a full LCIA method. It first elaborated and opened for stakeholder consultation a document scoping the starting points and work required to develop GLAM. Following 3 years of development and implementation, results were submitted for comments to more than 200 domain experts and LCIA experts in 13 impact category-specific virtual workshops, plus an in-person workshop in 2023 in Copenhagen and a virtual one in 2024 to synthesize final recommendations. Beta GLAM factors were opened for comments and consultation at SETAC-Europe 2024 (Sevilla) leading to the launch of GLAM V1.0.2024.10. Two virtual workshops were held in 2025 to gather further feedback from experts and the industry, identify potential modifications to extend GLAM midpoints and the normalization results in preparation for a comprehensive first update of the method.
GLAM development timeline
GLAM Stewardship (2026 onwards):
Current phase
The stewardship phase is designed to maintain the framework as a living, science-based global LCIA method. It emphasizes software implementation, continuous improvement, regular updates, and inclusive engagement with the global LCIA community. The stewardship approach follows the principles that have guided GLAM since its inception: transparency, inclusiveness, scientific rigor, and global applicability.
Phase 3 [2020- 2025]:
Phase 3 focused on establishing a comprehensive, consistent, and global Environmental Life Cycle Impact Assessment (LCIA) method, including classification, midpoint and damage characterization, normalization, and weighting to assess the life cycle impacts of products and services on human health, ecosystem, and natural resources.
Download Phase 3 output from the top of this page.
Three webinars were held during this phase, the recordings of which can be found below.
Phase 2 [2017-2019]:
Phase 2 focused on reaching a consensus on recommended indicators and characterization factors for life cycle impact assessment in the area of acidification and eutrophication, human toxicity, natural resources – mineral primary resources, land use impacts on soil quality, ecotoxicity. Cross-cutting issues were once again addressed.
Phase 2 output is summarized in GLAM vol 2 accessible for download here.
Phase 1 [2013-2016]:
Phase 1 focused on reaching a consensus on recommended indicators and characterization factors for life cycle impact assessment in greenhouse gas emissions and climate change impacts, health impacts of fine particulate matter, water use related impacts – water scarcity and human health impacts, land use related impacts on biodiversity. Cross-cutting issues were also addressed.
Phase 1 output is summarized in GLAM vol 1 accessible for download here.
Webinar recordings
Consult the recording of the stakeholder consultation for this project that took place on 28 August 2024 online to gain insight of how stakeholders were consulted in the process.
Consult the recording of the stakeholder consultation for this project that took place on 7 May 2020 online, with the participation of close to 200 people from around the world. 117 participants are already involved in the project, including 32% female and an encouraging 13% participants from Asia, Africa or Latin America and the Caribbean
Consult the recording of the stakeholder consultation for this project that took place on 18 November 2020 online. Topics included milestones in LCIA guidance, an overview of the GLAM task forces: human health; ecosystem quality; natural resource and ecosystem services; normalisation, weighting and cross-cutting issues.