What should a company and a verifier agree in the scope of work before a Greenhouse Gas (GHG) verification starts?
The GHG Protocol Corporate Standard says to agree upfront the scope, level and objective: which sites or information, desk or on-site review, the intended use of results, and the materiality threshold. It should stay flexible, Verifiers check that exclusions were not made just to improve the result, and companies should make the scope public for transparency and credibility.
What the agreement covers
- Which information is included, for example head office consolidation only or information from all sites.
- The level of scrutiny for chosen data, for example a desktop review or an on-site review.
- The intended use of the verification results.
- The materiality threshold, which is linked to the objectives of the verification.
Parts of an inventory can be verified
The standard says it is possible to verify the entire inventory or specific parts: by geographic location, business unit, facility or type of emissions. The work can also look at management issues, such as quality management procedures, managerial awareness, available resources, clearly defined responsibilities, segregation of duties and internal review procedures.
Flexible, and public
- The scope of work is influenced by what the verifier finds once work starts, so it must stay flexible enough for the verifier to complete the job.
- Verifiers will ensure that specific exclusions have not been made solely to improve the company's performance.
- To improve transparency and credibility, companies should make the scope of work publicly available. A clear scope also lets outside readers judge what the result covers.
Decide your goal before you hire
The standard asks a company to define its goals first and decide whether an external verification is the best way to meet them. Common reasons it lists: more credibility for reported emissions and progress to targets, more confidence among senior management, better internal accounting and reporting practice, and preparation for mandatory verification.
What a small plant should write down
My list, built from the standard's items above:
- Sites and period covered, and sites left out with the reason.
- Scopes and gases covered.
- Desk review or site visit for each site.
- Who will rely on the result, and what they will do with it.
- The materiality threshold and what it is a percentage of.
- Who on your side answers questions, and how soon.
A scope of work for a two-plant company
- Period: financial year 2025-26. Boundary: Plant A and Plant B, both owned and operated
- Plant A (2,400 tonnes of carbon dioxide equivalent): site visit. Plant B (7,600 tonnes): desktop review of bills and meter readings, visit only if the review finds a problem
- Intended use: the questionnaire of one named buyer
- Materiality: 5% of the inventory of the part verified, which is 120 tonnes for Plant A
- Exclusion: office electricity, with its estimated size written next to it
Example wording of mine, not from the standard. 5% of 2,400 tonnes is 120 tonnes. Whether the 5% applies per plant or to the whole is agreed with the verifier.
What Senseible does here
Senseible reads fuel invoices and electricity bills into monthly records. Its "Verified" status is an in-house check, not third-party assurance and does not replace a scope of work with a verifier.
- What to prepare for a verifier's site visit
- Who at an MSME should face the verifier
- How to choose a GHG verifier
- What a verifier evidence pack holds
- List of excluded emission sources
Sources: GHG Protocol Corporate Accounting and Reporting Standard (revised edition), chapter 10 (verification parameters, goals), GHG Protocol Corporate Standard (ghgprotocol.org)
Last reviewed 2026-11-05. This is the Corporate Standard's general guidance. A programme such as the Carbon Border Adjustment Mechanism (CBAM) or a buyer scheme may fix the scope for you, so check its rules first.