By Dr Souha Bel Haj Messaoud | Founder, Eco Fluent Solutions Updated: July 2026 | Reading time: 11 min
Ask most Validation and Verification Bodies (VVBs) whether their team is competent, and the answer is always yes. Ask them to demonstrate it, to show you the criteria, the assessment records, and the evidence of qualification for each role, and the conversation changes quickly.
This is the ISO 14066 problem. Not that VVBs lack competent people. But that competence is assumed, not systematically defined, assessed, and documented in a way that satisfies an accreditation assessor.
ISO 14066 is the standard that fixes that. And if you are building or operating a VVB, understanding it is not optional. It is one of the areas accreditation bodies examine most closely.
This guide walks you through what ISO 14066 actually requires, how it connects to your accreditation under ISO 17029, and the practical steps to build a competence system that holds up under external scrutiny.
What Is ISO 14066?
ISO 14066:2023 is the international standard that defines competence requirements for validation and verification teams working in the greenhouse gas (GHG) and environmental information domain.
It was published by the ISO (International Organization for Standardization) and most recently updated in 2023. It applies specifically to the people who perform validation and verification activities, not to the organisation as a whole, but to the individuals and teams doing the work.
In plain terms: ISO 14066 answers the question “what does a person need to know and be able to do before they are authorised to validate or verify a GHG declaration or environmental claim?”
It covers:
- The types of competence required (technical, process, behavioral)
- The roles within a validation or verification team and what each role demands
- How competence should be assessed and documented
- How competence should be maintained and developed over time
ISO 14066 does not stand alone. It is designed to be read and applied alongside:
- ISO 17029:2019 ; the general standard for VVBs, which sets the overall organisational requirements including the obligation to manage competence
- ISO 14065:2020 ; the sector-specific standard for GHG VVBs, which references ISO 14066 as the competence framework
- ISO 14064-3:2019 ; the methodology standard for validating and verifying GHG declarations
New to ISO 17029 and how these standards connect? Start here: [ The Complete Guide to ISO 17029 Accreditation (2026 Edition)]
Why ISO 14066 Matters for VVB Accreditation
ISO 17029 requires VVBs to have a functioning competence management system. But it does not specify in detail what competence looks like for GHG and environmental validation and verification activities. That specification is ISO 14066’s job.
When an accreditation body whether COFRAC (France), DAkkS (Germany), or UKAS (United Kingdom)… assesses your VVB, they will examine your competence system against both ISO 17029 and ISO 14066.
They are looking for evidence of three things:
1. You have defined what competence means for each role in your organisation.
Not generically (“our team has relevant experience”) but specifically, criteria per role, per activity type, per sector.
2. You have assessed your people against those criteria.
Not assumed qualification based on Resume’s alone, but a documented assessment process with a clear outcome: qualified, conditionally qualified, or not yet qualified.
3. You maintain records that demonstrate this.
Records that can be retrieved, reviewed, and verified during an assessment visit.
Without all three, your competence system does not meet the standard, regardless of how experienced your team actually is.
The Three Dimensions of Competence Under ISO 14066
ISO 14066 defines competence across three interconnected dimensions. Understanding all three is essential for building a system that works in practice.
1. Technical Competence
Technical competence refers to knowledge and skills specific to the subject matter being validated or verified. For a GHG-focused VVB, this includes:
- Understanding of GHG accounting principles and methodologies
- Knowledge of the specific sector(s) covered by your accreditation scope (e.g., energy industries, transport, agriculture)
- Familiarity with the applicable programmes and standards (e.g., EU ETS, CORSIA, ISO 14064-1)
- Ability to evaluate the technical plausibility of GHG data and calculations
- Understanding of measurement, monitoring, and reporting systems used by clients
Technical competence is sector-specific. A validator who is highly competent in the energy sector may not be qualified to work on agriculture or waste projects. Your competence system must reflect this, defining technical criteria per sector, not generically across all activities.
2. Process Competence
Process competence refers to knowledge and skills specific to how validation and verification activities are conducted, independently of the subject matter.
This includes:
- Understanding of the validation process versus the verification process. They are not the same, and ISO 14066 treats them separately
- Ability to plan a validation or verification engagement: scope definition, risk and materiality analysis, evidence strategy
- Skills in collecting, evaluating, and documenting evidence
- Understanding of sampling methodologies
- Ability to identify and resolve findings, raise corrective action requests, and document conclusions
- Knowledge of the reporting requirements for validation or verification statements
Process competence applies to all sectors. A team member may have strong technical knowledge of a sector but still lack the process skills to conduct a rigorous, compliant validation or verification engagement.
3. Behavioural Competence
Behavioral competence is the dimension most often overlooked and the one that can be most difficult to document.
It refers to the personal attributes and professional behaviours required to conduct validation and verification activities with integrity. Under ISO 14066, this includes:
- Professional scepticism: the ability to critically evaluate claims and evidence without accepting them at face value
- Independence of judgement: the ability to reach conclusions based on evidence, not on client pressure or commercial considerations
- Communication skills: the ability to explain findings clearly and professionally, both in writing and in direct client interactions
- Ethical conduct: adherence to confidentiality, impartiality, and professional standards
Assessors pay close attention to behavioral competence during the witness assessment phase of accreditation where they observe your team in action. A technically strong validator who defers to the client under pressure raises immediate concerns.
Roles Covered by ISO 14066
ISO 14066 defines competence requirements for the key roles within a validation or verification team. Each role has distinct requirements.
Validators and Verifiers
The individuals who perform the core validation or verification work. They must demonstrate all three dimensions of competence ; technical, process, and behavioral, for the specific activities and sectors they are authorized to work in.
Their qualification must be documented and periodically reviewed. A validator authorized for energy sector projects is not automatically authorized for transport or agriculture.
Technical Reviewers
The person responsible for independently reviewing the work of the validation or verification team before the final statement is issued. This role is critical for the separation of functions required under ISO 17029.
ISO 14066 requires that technical reviewers have sufficient competence to meaningfully challenge the team’s work, not just sign off. Their technical and process competence requirements are as demanding as those of the validators and verifiers themselves.
Team Leaders
Where a validation or verification engagement involves multiple team members, a team leader is responsible for planning, coordinating, and overseeing the work. ISO 14066 specifies additional competence requirements for this role, including the ability to manage team dynamics and resolve disagreements on technical findings.
How to Build a Compliant Competence System: Four Practical Steps
Step 1 : Define Competence Criteria by Role and Sector
Start by documenting exactly what competence means for each role in your organisation, for each sector and activity type within your accreditation scope.
This should produce a competence framework: a document or matrix that maps roles to required technical knowledge, process skills, and behavioral attributes, with specific criteria for each.
Do not write this at a generic level. “Relevant experience in GHG accounting” is not a criterion. “Ability to evaluate the completeness and accuracy of a Scope 1 emissions inventory against ISO 14064-1 requirements for the energy sector” is a criterion.
The level of specificity is what distinguishes a competence framework that satisfies an assessor from one that does not.
Step 2 : Assess Each Team Member Against the Criteria
Once your criteria are defined, each team member must be assessed against them. ISO 14066 does not prescribe a single method, assessment may involve:
- Review of qualifications, training records, and professional experience
- Written or oral knowledge assessments
- Observed performance during actual or simulated validation/verification activities
- Peer review of work products
What matters is that the assessment is documented, produces a clear outcome (qualified / conditionally qualified / not yet qualified), and is carried out by someone with the authority and competence to make that determination.
Step 3 : Document Everything and Maintain Records
Every qualification decision must be recorded. Your competence records should include, for each individual, the criteria assessed, the evidence reviewed, the assessment method used, the outcome, and the date.
These records must be retrievable. During an accreditation assessment, the assessor may ask to see the qualification record for a specific team member who performed a specific validation activity. If that record does not exist or cannot be found, it is a non-conformity.
Step 4 : Review, Monitor and Develop Competence Over Time
Competence is not a one-time determination. ISO 14066 requires that competence is monitored and maintained, through ongoing performance review, continuing professional development, and periodic reassessment.
This means having a process to identify competence gaps, a mechanism for providing development opportunities (training, mentoring, supervised practice), and a schedule for reassessing team members at defined intervals.
It also means having a process for managing situations where a team member’s competence is found to be insufficient, including what happens to activities they have already performed.
The Most Common Competence Gaps Assessors Find in VVB Systems
Based on direct experience accompanying VVBs through accreditation preparation, the following gaps appear most consistently:
Competence criteria written at the wrong level of specificity.
Criteria that are too generic do not allow a meaningful assessment and do not satisfy assessors. The standard expects criteria precise enough to be assessed objectively.
Resume’s used as qualification evidence without a documented assessment.
A Resume or a CV demonstrates background. It does not demonstrate competence against defined criteria. Assessors treat CV-only qualification as insufficient.
No separation between technical competence and process competence in the framework.
These are distinct dimensions under ISO 14066. A single “competence record” that treats them as one does not reflect the standard’s structure.
Technical reviewer qualification not documented separately.
Many VVBs document validator and verifier qualifications but treat technical review as an informal step. ISO 14066 is explicit: reviewers must be qualified for the role.
No reassessment schedule or process for managing competence gaps.
A static competence system, where qualification is determined once and never revisited, does not meet the standard’s requirements for ongoing monitoring.
Concerned about your current competence system? Read how ISO 17029 assessors evaluate the full picture: [ ISO 17029: The Invisible Backbone of Trust — Why Accreditation Bodies Face Their Most Challenging Era?]
ISO 14066 and ISO 17029: How They Work Together
ISO 17029 creates the obligation to manage competence. It requires VVBs to have a functioning system for defining, assessing, and maintaining the competence of all personnel involved in validation and verification activities.
ISO 14066 provides the specification. It tells you what competence means for GHG and environmental validation and verification teams, and how it should be structured.
In accreditation terms, you cannot satisfy the competence requirements of ISO 17029 without implementing ISO 14066. They are complementary, not alternative.
The practical consequence: your competence system must be designed with both standards in view. A system built only on ISO 17029’s general requirements, without the specificity of ISO 14066, will have gaps that assessors will identify.
Frequently Asked Questions About ISO 14066
Does ISO 14066 apply to all VVBs or only those working on GHG activities?
ISO 14066 is specifically designed for VVBs working in the GHG and environmental information domain. If your scope includes GHG validation or verification : carbon projects, EU ETS, CORSIA, CSRD sustainability assurance… then ISO 14066 applies to your competence system. VVBs working exclusively outside the GHG domain would look to other sector-specific competence standards.
Can a single person hold multiple roles under ISO 14066?
A team member can be qualified for multiple roles, for example, both as a verifier and as a team leader, provided their competence has been assessed and documented for each role separately. What ISO 17029 prohibits is the same individual acting as both the validator/verifier and the independent technical reviewer on the same engagement. The roles are separate by design to ensure independent oversight.
How often does competence need to be reassessed under ISO 14066?
ISO 14066 does not specify a fixed reassessment interval. It requires that competence is monitored on an ongoing basis and reassessed when relevant changes occur (new sectors, new methodologies, performance concerns, extended periods of inactivity). In practice, most VVBs implement a defined reassessment cycle, typically every two to three years, combined with annual performance monitoring. The specific interval should be defined in your competence management procedure.
What counts as valid evidence of technical competence?
Valid evidence includes formal qualifications relevant to the sector, documented professional experience with specific activities, completed training with verified outcomes, results of knowledge assessments, and observed performance records. The key principle is that evidence must be objective and assessable, not self-declared. Your competence procedure should specify exactly which types of evidence are accepted for each role and criteria.
What happens if a team member does not meet the competence criteria?
ISO 14066 requires that this situation is managed, not ignored. Options include supervised practice under a qualified team member, targeted training, or exclusion from certain activities until competence is demonstrated. The outcome and any restrictions must be documented. If work has already been performed by a team member whose competence is subsequently found to be insufficient, your non-conformity and corrective action process must address this.
Is ISO 14066:2023 significantly different from the previous version?
The 2023 update refined the competence framework and aligned it more closely with the updated ISO 14065:2020 and the requirements of ISO 17029:2019. The core structure ; technical, process, and behavioral competence across defined roles, is consistent with the previous version, but the 2023 edition provides more precise language and clearer alignment with current accreditation expectations. If your competence system was built against the previous version, a gap review against the 2023 edition is advisable.
Is Your VVB Competence System Accreditation-Ready?
A credible VVB is only as strong as the competence of its team. ISO 14066 gives you the framework to build that credibility systematically but implementing it correctly requires precision, not just effort.
At Eco Fluent Solutions, I work with VVB teams to design and strengthen competence systems that meet the requirements of ISO 14066 and ISO 17029, from defining role-specific criteria to structuring assessment processes and building the documentation that holds up under external scrutiny.
→ Request your accreditation readiness audit — a structured review of your VVB system, including your competence framework, delivered by a specialist with direct accreditation preparation experience.
Related articles:
- The Complete Guide to ISO 17029 Accreditation (2026 Edition)
- ISO 17029: The Invisible Backbone of Trust — Why Accreditation Bodies Face Their Most Challenging Era?
- ISO 14019:2026 — New Requirements for Verification Bodies
- ISSA 5000 vs ISAE 3000: Which Assurance Standard Should VBs Choose for CSRD?]
Dr Souha Bel Haj Messaoud is the founder of Eco Fluent Solutions, a Paris-based consultancy specialising in ISO management systems, sustainability governance, and VVB accreditation readiness. She has supported organisations across Europe, Asia, and North Africa in building accreditation-ready systems under ISO 17029, ISO 14065, and ISO 14066. Learn · Comply · Lead — ecofluentsolutions.com
