Lifecycle assessment
Understand environmental trade-offs across a product system, not only at one facility.
Define the question
Set the functional unit, system boundary and intended decision before collecting data. Two products can only be compared meaningfully when they deliver the same function. Document exclusions and the reasons for them.
Build the inventory
Gather material, energy, transport, use and end-of-life information. Separate measured information from estimates and secondary datasets. The quality of a result depends on how well the inventory represents the system.
Interpret the result
Examine sensitivity, uncertainty and the stages that drive the result. Avoid reducing a multi-impact question to one convenient indicator. State what the analysis supports and what further evidence would change the decision.