VERIFIER ACCREDITATION REGIMES

Verifier accreditation regimes determine which organisations are qualified to check carbon-removal projects and their reported results. A government or certification-scheme owner requires verification providers to obtain approval from an accreditation body, an institution that assesses their technical competence and independence. That body examines staff qualifications, observes verification work and carries out periodic checks, with power to suspend or withdraw approval. A provider approved for one method may need additional assessment before verifying another. These arrangements help project developers find competent verifiers and give buyers greater confidence in their conclusions. They govern the organisations performing verification, rather than setting the underlying rules for calculating removals or deciding each project's eligibility.

Policymakers should first establish whether existing accreditation bodies can assess removal verifiers or need additional expertise. Checking underground CO₂ storage, soil carbon and marine interventions requires different skills, so approval must identify the methods and tasks it covers. Countries or schemes may agree to accept approval issued elsewhere, provided the assessment requirements are equivalent. Independence rules should address fees paid by projects, consulting relationships and staff rotation. Assessors need to observe actual verification work and review subsequent performance. Where a removal standard includes environmental or community safeguards, the verifier's ability to assess those requirements should also be tested.

Using established accreditation bodies can give a new removal scheme access to experienced assessors and approved verification providers. Agreements to recognise each other's accreditation decisions can allow qualified firms to serve several countries without repeating the full approval process. This can expand the choice of verifiers and reduce delays for developers. Periodic reviews also give scheme owners a way to identify recurring verification errors and correct requirements or training. Buyers and financiers can use the public record of approved providers, permitted activities and disciplinary decisions when assessing the reliability of removal claims.

Requirements introduced faster than assessors and verifiers can be trained may delay project approval. Weak requirements create the opposite risk, allowing projects to seek out providers willing to accept poor evidence. A verifier paid by the project it assesses can face pressure to overlook problems, and disclosure alone may not resolve that conflict. Separate approvals for similar schemes can multiply costs without improving quality. Continued checks, accessible complaints procedures and credible suspension powers are therefore needed after initial accreditation, particularly when providers enter unfamiliar removal methods.

Accreditation bodies should assess the number of qualified verification providers by method, project waiting times, findings from periodic checks, complaints and withdrawals of approval. Comparisons of verification results for similar projects can reveal inconsistent practice. These findings should guide training, changes to approved activities and disciplinary action.

Accreditation bodies should design assessments and identify the expertise their assessors need. Certification-scheme owners and scientists can specify the skills required for each removal method, while verification firms explain training needs and operating costs. Regulators should agree how concerns trigger investigation or enforcement. Developers, buyers and civil society can identify inconsistent practice and test whether public accreditation records are understandable.

International schemes can require accredited verification and agree how participating countries recognise approved providers. Supranational authorities can establish common requirements, while national accreditation bodies assess providers and maintain their approval. Authorised private accreditation bodies can perform this function where the applicable system permits them. CORSIA, the international aviation carbon scheme, uses national accreditation bodies to assess verifiers against common standards. Subnational governments and philanthropies can support training, but that role alone does not authorise them to accredit verification providers.