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Boundaries and categories: reading ISO 14064-1:2018 correctly
Many inventories in this region were built on the GHG Protocol's three scopes and are now being reported against ISO 14064-1:2018. The two are compatible in substance but not in structure, and the 2018 edition adds a requirement that the older habit does not cover: you must state why the indirect emissions you included are the significant ones.
Six categories, not three scopes.
| Category | What it covers | Usually maps to |
|---|---|---|
| Category 1 | Direct GHG emissions and removals — from sources owned or controlled by the organization. | Scope 1 |
| Category 2 | Indirect GHG emissions from imported energy — electricity, heat, steam, cooling. | Scope 2 |
| Category 3 | Indirect GHG emissions from transportation. | Parts of Scope 3 |
| Category 4 | Indirect GHG emissions from products used by the organization. | Parts of Scope 3 (upstream) |
| Category 5 | Indirect GHG emissions associated with the use of products from the organization. | Parts of Scope 3 (downstream) |
| Category 6 | Indirect GHG emissions from other sources. | Remaining Scope 3 |
Significance is now something you have to justify.
The 2018 edition requires the organization to establish and apply criteria for determining which indirect emissions are significant, and to report those criteria. In practice this replaces the familiar defence — "we reported the Scope 3 categories we had data for" — with a stated basis: magnitude, level of influence, risk, sector guidance, stakeholder expectation, or a documented combination.
This is one of the most common findings in first-cycle ISO 14064-1 verifications. The inventory itself is often sound; what is missing is the written criterion explaining why five indirect sources were included and eleven were not. Without it, completeness cannot be tested, because there is nothing against which to test it.
The criterion does not have to be elaborate. It has to exist, be applied consistently, and be capable of being read by someone who did not build the inventory.
Five decisions to record before the data work starts.
The consolidation approach
Control (financial or operational) or equity share. State it once, apply it everywhere, and reconcile it to the group structure. Changing it mid-inventory invalidates the comparison.
Organizational boundaryThe entity and site list
Every legal entity and site inside the boundary, with ownership percentage and the treatment of joint arrangements. This list is the completeness test.
Boundary evidenceThe significance criteria
The written basis for deciding which indirect emissions are reported, applied to every category from 3 to 6, including those the criteria exclude.
Clause requirementThe base year and the recalculation policy
The base year, why it was chosen, and the events that trigger recalculation — structural change, methodology change, error correction above a stated threshold.
ComparabilityThe GWP source
Which IPCC Assessment Report the global warming potentials come from, and the version applied consistently across all gases and all years shown.
Quantification
If your inventory is already built on scopes.
Nothing has to be rebuilt. Report against ISO 14064-1:2018 categories, keep a mapping table showing how each existing data stream lands in a category, and add the significance criteria you were applying implicitly. That is usually two documents and a restructured report — not a new inventory.
Where the organisation also reports to the GHG Protocol for a disclosure platform, both presentations can coexist provided the underlying data is identical and the mapping is documented. A verifier will test that they reconcile; a difference between them that nobody can explain is a finding.
Primary sources
- ISO 14064-1:2018 — Specification with guidance at the organization level, including the six categories and significance criteria — www.iso.org/certification.html (checked 01 September 2026)
- ISO 14064-3:2019 — verification requirements applied to organizational inventories — www.iso.org/certification.html (checked 01 September 2026)
- ISO 14066:2023 — competence requirements for validation and verification teams — www.iso.org/certification.html (checked 01 September 2026)
Editorial note. Author and technical review above are editorial functions. They are separate from the independent technical review and the decision functions required under ISO/IEC 17029:2019, which apply to validation and verification engagements and not to published articles. Nothing on this page is advice on a specific engagement, and nothing here extends or replaces the accreditation records.
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