---
term: "Life Cycle Assessment (LCA)"
aliases: ["LCA", "life cycle analysis"]
category: Method
updated: 2026-09-08
canonical: https://verdatir.com/glossary/life-cycle-assessment
publisher: Verdatir (https://verdatir.com)
---

# Life Cycle Assessment (LCA)

> A systematic method, standardised in ISO 14040 and ISO 14044, for quantifying the environmental impacts of a product or service across its entire life cycle, from raw material extraction to end of life.

Life Cycle Assessment (LCA) is the method underneath almost every product-level environmental claim, including EPDs and product carbon footprints. It compiles the inputs and outputs of a product system and evaluates their potential environmental impacts over the life cycle.

## The four phases

ISO 14040 and ISO 14044 structure an LCA in four iterative phases:

1. **Goal and scope definition**: the purpose of the study, the functional unit, the system boundary, allocation rules and data requirements.
2. **Life cycle inventory (LCI)**: collection and quantification of all relevant flows of energy, materials and emissions.
3. **Life cycle impact assessment (LCIA)**: translation of inventory flows into impact categories such as climate change, acidification or water use, using characterisation factors.
4. **Interpretation**: identification of significant issues, sensitivity and uncertainty checks, and conclusions consistent with the goal.

## Foreground and background data

The practitioner collects primary data for the processes the organisation controls and uses background databases for upstream processes such as electricity generation or raw material production. The choice of background data is one of the largest drivers of differences between studies.

## Why verified LCAs still differ

Two LCAs of similar products can be individually correct yet not comparable if they use different boundaries, allocation methods or datasets. Product Category Rules exist to close that gap for declarations. Our article on why verified LCAs still aren't comparable explores this in depth.

## Where Verdatir fits

Verdatir checks LCA studies and reports for completeness and consistency against ISO 14040/44 and the relevant PCR, so reviewers spend their time on judgment rather than on hunting for missing clauses.

## Sources

- [ISO 14040:2006 — Life cycle assessment — Principles and framework](https://www.iso.org/standard/37456.html)
- [ISO 14044:2006 — Life cycle assessment — Requirements and guidelines](https://www.iso.org/standard/38498.html)