Glossary›Emissions accounting and measurement›Scope 3 materiality screening
Glossary term
Cluster D · D6
Tier 1 · differentiator
Scope 3 materiality screening
Definition
Scope 3 materiality screening is the structured first pass across all fifteen categories that determines which are material enough to measure in detail. It uses rough estimates from spend, activity proxies or sector knowledge, applies a threshold fixed in advance, and records the decision for every category. The screening is evidence in its own right.
· Appendix B paragraph B32, Appendix D paragraph 18 and Appendix D paragraph B25 ·
Practice, in force
On this page
In practice
The screening is the cheapest document in the whole Scope 3 programme and the one that carries the most weight, because it is the only thing standing between a reasoned exclusion and an unexplained omission.
The distinction it exists to manage is between considering a category and measuring one. Appendix B paragraph B32 requires an entity to consider its entire value chain and all fifteen categories. Nothing requires it to measure all fifteen. Appendix D paragraph B25 provides that an entity need not disclose information otherwise required by the standard if that information is not material, even where the standard describes the requirement as a minimum. The screening is what converts that permission into a defensible position.
Three things make a screening hold up, and all three are procedural rather than technical.
The threshold is fixed before the scoring. A threshold set after the results are known is the first thing a reviewer looks for and the file dates reveal it. Fix the threshold, write down why, then score.
It covers all fifteen, including the ones that are obviously nil. A screening that only discusses the categories the entity happened to have data for is not a screening; it is a description of the dataset. Categories assessed as not applicable need a one-line reason, and “we have no franchises” is a complete reason.
The exclusion argument is the right one. This matters more than it sounds. The instinct is to argue that data could not be obtained. For most categories, and especially for related-party investments, that claim is false and collapses on the first question: you share directors, you can simply ask. The argument that survives is that quantifying an immaterial category produces no benefit however cheap the data is, which is where Appendix B paragraph B10’s balanced consideration of costs and benefits actually operates. “We can get it and it is not worth getting” holds. “We cannot get it” does not.
Materiality here is also not purely a tonnage test. Appendix D paragraph 18 frames materiality as whether omitting, misstating or obscuring the information could reasonably be expected to influence the decisions of primary users. A category can be modest in tonnage and material because it is the entity’s central transition risk, or because a lender, a customer or a regulator is known to be looking at it.
Method note that saves a great deal of money: screen on spend. A first-pass spend-based estimate across the whole accounts payable ledger, mapped to sector factors, is cheap, covers 100 per cent of the upstream population and is good enough to rank categories. It is not good enough to disclose, and nobody should confuse the two, but as a ranking instrument it is what the screening needs.
What the assurer does with it
Where a category has been excluded, the assurer tests the screening rather than the exclusion. There is nothing else to test: the category has no number.
They ask when the threshold was set relative to the scoring, who approved the screening, and what basis each category’s assessment rests on. Then they sanity-test the conclusions against the entity’s own commercial records: the creditors listing by spend, the capital additions, the revenue analysis by product and channel, the investments note.
They accept a dated screening covering all fifteen categories, with a threshold fixed in advance, a stated basis per category, and approval recorded at a level consistent with the entity’s significant judgement process. They reject a screening produced after the exclusion decision, an exclusion argued on data unavailability, a screening silent on a category the entity’s own financial records show it plainly has, and a threshold expressed only as a percentage of a total that itself depends on the excluded categories.
The last one is worth naming because it is circular and common: setting the threshold at five per cent of total Scope 3 when the total Scope 3 cannot be known until the screening is done. Express the threshold against something independent (revenue, total spend, or total Scope 1 and 2) and the circularity disappears.
Where a category was excluded last year and is included this year, they treat it as a change requiring restatement of the comparative, and they ask what changed: the business, the data, or the judgement.
Commonly confused with
The materiality threshold an assurance provider sets for the engagement, which is a quantitative engagement parameter set by the assurer and has nothing to do with which categories the entity measures. Also confused with a full Scope 3 calculation: a screening is deliberately rough and is not a disclosable figure.
Timing and relief
The screening should exist before the first reporting period ends, even though Scope 3 disclosure is relieved in that period under Appendix C paragraph C4(b). The reason is operational rather than regulatory: the screening determines which categories need a full year of year-two data, and that data collection has to start on day one of year two.
Sources
1
2
Corporate Value Chain (Scope 3) Accounting and Reporting Standard, full text
GHG Protocol
3
ASSA 5000 General Requirements for Sustainability Assurance Engagements
AUASB
Review status
Review required
Last reviewed
15 September 2026
Editorial pass, unsigned
Reviewer required
Carbon accounting specialist and registered company auditor
Next scheduled review
1 July 2027
Part of
Cluster D, Emissions accounting and measurement
49 terms from the head term carbon accounting down to individual Scope 3 categories and the mechanics of factors, boundaries and data quality. The largest cluster in the glossary.
Related terms
The parent obligation the screening bounds
The fifteen positions a screening has to record
The separate quantitative parameter the assurer sets for the engagement
Related questions
How do we work out which Scope 3 categories are material for us?
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You screen all fifteen GHG Protocol categories, estimate each roughly off accounts payable spend, and document why you included or excluded each one. The screen is the deliverable as much as the answer, because the practitioner will test the reasoning behind an exclusion at least as hard as the numbers behind an inclusion. Expect the answer to be concentrated in a handful of categories.
Do we have to report Scope 3 in year one?
+
No. AASB S2 gives first-time reporters relief from disclosing Scope 3 greenhouse gas emissions in their first annual reporting period, and Scope 3 is required from the second year. Taking the relief in year one is normal, but the supplier data work needs to start in year one anyway.
Can we estimate Scope 3 and still pass assurance?
+
Yes. Estimates are expected in Scope 3 and are not a problem for assurance in themselves, because what fails is an undocumented estimate. The practitioner tests whether the method is appropriate and disclosed, the inputs are traceable, the application is consistent, and the estimation uncertainty is described honestly.
Where this sits commercially
Carbonhalo writes the screening with the threshold fixed before scoring, which is the difference between a reasoned exclusion and an unexplained omission.
Other terms in this cluster
Scope 3 materiality screening