SM5002 Chap.10 Writing the Single-Use Product LCA Report

Writing the Single-Use Product LCA Report

The task in one paragraph

The largest single assessment in the module is an individual report of at most 1,000 words describing a life cycle assessment you build yourself. You pick a common single-use healthcare item, such as surgical gloves, a syringe, suction tubing, a face mask or drapes, and model it from cradle to grave in openLCA.

The background data come from Ecoinvent, using cut-off unit processes, and the impact method is ReCiPe 2016 under the Hierarchist perspective.

The report is due by the end of Sunday 15 November 2026. Its stated purpose is to show that you understand LCA method well enough to choose inventory data, defend your assumptions, read your own results critically and present them clearly.

Where the inventory can come from

Three routes are allowed: a life cycle assessment already published in a peer-reviewed journal, publicly available manufacturer information sheets, and other reputable public sources.

Whichever you use, every assumption for every life cycle stage needs a justification and a reference, and the report must say where every primary and secondary figure came from. The life cycle has to include raw material extraction and processing, manufacture of the final form, transport, use where it is relevant, and disposal at end of life.

There is one important condition.

If you start from a published paper, you cannot simply rebuild it. The brief asks you to move the product into a hypothetical alternative setting, for instance by changing where it is made, how far and by what mode it travels, where it is used, or how it is disposed of.

The intent is that you make and justify modelling decisions of your own, rather than reproduce someone else's.

The four required sections

Goal and scope sets out the aim, the functional unit, the system boundary and the assumptions, and it must include a figure of the boundary showing which life cycle stages are in the model.

The life cycle inventory section is a table listing each Ecoinvent process used, the particular provider selected for it, and the quantity assumed. Impact assessment reports the ReCiPe 2016 Hierarchist results with figures or tables that summarise them.

Interpretation then analyses contributions by major life cycle stage, names the largest contributors to impact, and discusses uncertainty and limitations.

Alongside the text, three openLCA screenshots are required: the inputs and outputs of your process, the life cycle impact assessment results, and the contribution analysis.

The assignment booklet shows a contribution tree for the climate change category as the model for the third. The report uses Vancouver referencing, and the 1,000 word limit does not count tables, figures or references, which is a strong hint that numbers belong in tables and the prose belongs to reasoning.

How the rubric weights the work

Six criteria make up the mark.

Understanding and application of LCA methodology carries a quarter of it and is shown throughout the report, wherever you justify a choice. The life cycle inventory criterion is worth twenty percent, the most of any single section. Goal and scope definition including the system boundary, impact assessment using ReCiPe, and interpretation, analysis and synthesis of results are worth fifteen percent each.

Referencing and presentation, including correct Vancouver style, carries the remaining ten percent.

Building a defensible inventory

The workshop exercise on inventories gives a template worth copying in form.

A pair of non-sterile nitrile gloves is broken into material mass, electricity for manufacture and for air-leak testing, packaging, three freight legs and two waste routes, and each row names an Ecoinvent market process with its geography. Freight is entered as mass multiplied by distance, so the mass that travels, product plus packaging, has to be converted to kilograms before multiplying by each leg's kilometres.

Separate legs need separate rows because a diesel lorry and a container ship are different providers with different emissions.

When you move the product into an alternative context, the inventory is where the change becomes visible. A new country of manufacture means new electricity providers, a new route means new distances and possibly new transport modes, and a different end-of-life pathway swaps the waste process.

Each of those edits should be traceable from the table to a sentence of justification and a reference.

Writing the interpretation

Interpretation is where many reports fall short, because it is written last and in a hurry. A strong section names the stage or process that dominates each headline category, explains why in physical terms, and then tests that explanation against the assumptions that were weakest.

If a freight distance was estimated, say so and say which way an error would move the result. If a provider was a proxy, name it as a limitation. End with what the findings imply for the product's choice or design, which is the reason anyone commissions an LCA.

A sensible order of work

Although the report is read in the order goal, inventory, impact, interpretation, it is easier to write in a different order.

Settle the product and the alternative context first, because every later number depends on them. Build and check the inventory table next, making sure each row has a provider, a quantity in the right unit and a reference; a gram entered where openLCA expects a kilogram silently scales the whole result.

Run the ReCiPe Hierarchist assessment, take the three screenshots, and read the contribution analysis before writing a word of interpretation. Only then draft the goal and scope, so that the stated aim, functional unit and boundary describe the model you actually built rather than the one you planned.

Leave time for a final pass against the brief.

Check the boundary figure, the three screenshots, the provider column, the data sources, the Vancouver reference list and the word count, which stops at 1,000 once tables, figures and references are set aside.

What this chapter covers

• 01

  Choosing a single-use product and its data sources

• 02

  Modelling an alternative context instead of replicating a paper

• 03

  Goal, scope and the system boundary figure

• 04

  The inventory table with Ecoinvent providers and quantities

• 05

  ReCiPe 2016 Hierarchist results and the three screenshots

• 06

  Contribution analysis, uncertainty and limitations

• 07

  Rubric weights and the 1,000 word budget

Worked example · free

Computing freight rows for a glove inventory

Key terms

Cradle to Grave

A boundary covering raw materials, manufacture, transport, use and end-of-life disposal of a product.

Ecoinvent Provider

The particular background process in the Ecoinvent database that supplies a flow, including its geography.

Alternative Context

A hypothetical change of manufacture country, transport, country of use or disposal route applied to a published inventory.

Contribution Analysis

A breakdown of an impact result by life cycle stage or process to show which parts drive it.

Hierarchist Perspective

The ReCiPe perspective based on the most common policy principles on time frame and related issues, required for this report.

System Boundary Figure

A diagram in the goal and scope section showing which life cycle stages the model includes.

Cut-off Unit Process

An Ecoinvent dataset in which recyclable materials pass burden free to recycling, recycled materials carry only recycling impacts, and processes are kept at unit level.

Writing the Single-Use Product LCA Report FAQ

Assessment move

Build the inventory table first and make every row traceable to a provider, a quantity and a reference before writing any prose. Then draft interpretation from the contribution analysis, and only after that write goal and scope so that it describes the model you actually built.