ISO Standards & QET Registry Verification

The ISO Standards Stack Behind EarnDLT's QET Registry

The QET framework is not aligned with a single ISO standard — it is built on a layered stack of eight standards, each governing a distinct function: how carbon intensity is calculated, how allocations are made across co-products, how heating values are determined, how verifiers are accredited, how measurement laboratories qualify, and how environmental claims are substantiated as product-level carbon footprints. The Payne Institute at Colorado School of Mines independently examined this architecture in its 2025 whitepaper on environmental attribute tokens, validating QET-LNG as a credible instrument for EU Methane Regulation compliance.

This page documents the complete standards stack and explains precisely what role each standard plays in a QET token — from inlet measurement to final retirement on the blockchain registry.

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Why a Complete Standards Stack Matters

A carbon intensity certificate is only as credible as the methodology behind it. In regulated markets — EU Methane Regulation, CBAM, CSRD/ESRS E1, FuelEU Maritime — buyers, regulators, and auditors will ask not just "what is the carbon intensity?" but "how was it measured, who verified it, how were co-products handled, and is the verifier independently accredited?"

A registry that cites only a single verification standard cannot answer all of those questions. EarnDLT's methodology architecture was designed from the outset to address every layer: quantification, product-level footprinting, co-product allocation, heating value determination, verification, verifier accreditation, and measurement laboratory qualification. Each layer has a corresponding ISO standard. Together they form a complete, auditable chain from physical operations to digital token.

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The Eight ISO Standards in the QET Framework

ISO 6338:2023 — LNG Plant GHG Emissions Calculation

Role in QET-LNG: The foundational quantification standard. ISO 6338:2023 defines the system boundary for an LNG liquefaction plant (natural gas inlet through LNG loading arms), specifies emission source categories (combustion, vented, fugitive, process-specific), and provides the core carbon intensity formula: (Total LNG Plant Emissions × LNG Allocation Factor) / Net LNG Energy Production (MMBtu). Every QET-LNG token is calculated in strict accordance with this standard.

Why it matters for buyers: ISO 6338:2023 is the only internationally recognized standard specifically written for LNG plant GHG emissions. Its use ensures that QET-LNG carbon intensity values are calculated consistently across different facilities and are directly comparable — a prerequisite for portfolio-level procurement decisions by European utilities and LNG importers.

ISO 14064-3:2019 — GHG Verification and Validation

Role in QET framework: The verification backbone for all QET types. ISO 14064-3:2019 specifies the principles, requirements, and guidance for verifying and validating GHG assertions. It governs how third-party verifiers plan and conduct verification engagements, assess materiality, gather evidence, and issue verification opinions.

Application to QETs: QET-LNG verification uses materiality thresholds of 5% for individual token batches and 2% for portfolio aggregations, consistent with ISO 14064-3 requirements. The same standard governs verification of QET-NG and QET-RNG. All verification statements referencing the QET registry must be issued under ISO 14064-3.

Why it matters for buyers: ISO 14064-3 is the universally accepted GHG verification standard. A verification statement issued under this standard is recognized by EU regulators, CSRD auditors, and carbon market counterparties without further qualification.

ISO 14067:2018 — Carbon Footprint of Products

Role in QET framework: The product carbon footprinting standard that gives each QET its legal and commercial basis as a product-level environmental attribute certificate. ISO 14067:2018 specifies principles, requirements, and guidelines for quantifying the carbon footprint of a product — where "product" includes both goods and services.

Application to QETs: Each QET token represents the verified carbon intensity of 1 MMBtu of energy product (LNG, natural gas, or RNG). This is a product carbon footprint in the ISO 14067 sense. The standard's requirements for functional unit definition, system boundary documentation, and environmental claim substantiation are all embedded in the QET data schema.

Why it matters for buyers: ISO 14067 is the standard cited in EU supply chain disclosure frameworks including CSRD/ESRS E1 (Scope 3 categories 1 and 4) and is directly referenced in several EU Methane Regulation implementing regulations. A QET token structured as an ISO 14067-compliant product carbon footprint is portable across multiple compliance frameworks — not just one.

ISO 14044:2006 — Life Cycle Assessment / Multi-Product Allocation

Role in QET-LNG: The standard that governs how emissions are allocated between LNG and co-products at multi-product facilities. When an LNG plant also produces LPG, condensate, or exported power, the total facility emissions must be apportioned to each product stream. ISO 14044 defines the hierarchy of allocation methods: first, physical relationships such as energy content; second, mass; third, economic value.

Application to QET-LNG: The QET-LNG methodology's Section 4.2 (Multi-Product Allocation Requirements) and Step 2 of the calculation framework implement the ISO 14044 hierarchy directly. The LNG allocation factor — which typically ranges from 0.85 to 0.98 depending on co-product volumes — is calculated using energy content (HHV basis) as the primary method, per ISO 14044 requirements. When energy allocation is not feasible, mass or economic allocation may be used, with documented justification.

Why it matters for buyers: Without ISO 14044-compliant allocation, the carbon intensity attributed to LNG could be artificially low (if emissions are underallocated) or artificially high (if co-products are not properly credited). The allocation factor is disclosed in every QET-LNG token's data schema, giving buyers full transparency into how the CI value was derived at multi-product facilities.

ISO 6976:1995/2016 — Natural Gas Heating Value Calculation

Role in QET framework: The technical standard for calculating calorific values and relative density of natural gas from compositional analysis. In the QET-LNG context, this standard is applied in Step 4 of the carbon intensity calculation: Net LNG Energy (MMBtu) = LNG Production (tonnes) × LNG Heating Value (MMBtu/tonne).

Application to QETs: LNG heating values must be determined through regular compositional analysis using standard calculation methods — ISO 6976 or GPA 2172. The heating value is the denominator of the carbon intensity calculation: a 1% error in the heating value produces a 1% error in the reported CI. QET-LNG tokens disclose the heating value used in the calculation, ensuring this input is verifiable. For QET-NG tokens, the same heating value precision requirements apply to natural gas throughput at custody transfer.

Why it matters for buyers: Heating value directly affects the MMBtu denominator and therefore the kgCO₂e/MMBtu carbon intensity figure. ISO 6976 compliance ensures that compositional analysis is conducted with traceable methods, reducing the risk of systematic understatement of CI through manipulated heating value inputs.

ISO 14065:2020 — Competence Requirements for GHG Validation/Verification Bodies

Role in QET framework: The accreditation standard for organizations that provide GHG verification and validation services. ISO 14065 specifies the requirements that a verification body must meet — including organizational competence, impartiality, and quality management — to be recognized as qualified to issue verification opinions under ISO 14064-3.
Application to QET verification: QET-LNG Section 8.2 requires that lead verifiers demonstrate a minimum of three years of ISO 14064-3 experience and that verification body accreditation meet ISO 14065 requirements. The comprehensive JSON token schema includes an explicit accreditation field for the verification organization, which must reference ISO 14065 compliance. This requirement is non-negotiable: a verification statement from a non-accredited body does not satisfy QET registry standards.
Why it matters for buyers: ISO 14065 accreditation is the buyer's assurance that the verification organization is independent, competent, and subject to oversight. Without this requirement, any entity could issue a "verification statement" without qualification. EarnDLT's verification requirements align with the same accreditation standards used by the EU ETS and major carbon crediting registries.

ISO 17025:2017 — Competence of Testing and Calibration Laboratories

Role in QET framework: The accreditation standard for measurement and testing laboratories. In the QET-LNG context, this standard applies to the organizations that conduct GHG measurements — particularly direct emissions monitoring, gas composition analysis, and custody transfer measurement — as distinct from the organizations that verify those measurements.

Application to QET-LNG: QET-LNG Section 9.2's comprehensive JSON schema includes an accreditation field for the measurement organization that explicitly references ISO 17025. Measurement organizations conducting direct emissions quantification, LNG compositional analysis, or flow measurement used as the basis for QET token production must be able to demonstrate ISO 17025-compliant laboratory practices, including instrument calibration traceable to national standards, documented measurement procedures, and proficiency testing.

Why it matters for buyers: The distinction between ISO 17025 (measurement) and ISO 14065 (verification) is critical. Even if a verifier is fully accredited, the underlying measurements can still be unreliable if the measurement laboratory lacks proper quality controls. ISO 17025 closes this gap by setting a floor for measurement quality that is independent of the verification process.

ISO 14064-3:2019 Reference to IPCC AR5 GWP Values

Note: While not a separate ISO standard, the QET framework's normalization methodology requires explicit reference to IPCC AR5 100-year Global Warming Potential values for CO₂ equivalent conversion: CH₄ = 28, N₂O = 265. This basis is disclosed in every QET token and consistent with the GHG Protocol Corporate Standard and ISO 14067 requirements.

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How the Standards Map to Each QET Token Type

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How ISO Requirements Map to the QET Data Schema

Every QET token is represented as a structured JSON object stored on the EarnDLT blockchain registry. The schema fields are not arbitrary — each maps directly to a specific ISO requirement:

carbonIntensity_kgCO2e_per_MMBtu → ISO 6338:2023 (formula) + ISO 14067:2018 (product functional unit: 1 MMBtu)

allocationFactor + allocationBasis → ISO 14044:2006 (energy content allocation hierarchy)

lngHeatingValue_MMBtu_per_tonne → ISO 6976 (compositional analysis and HHV calculation)

uncertainty + confidenceLevel → ISO 14064-3:2019 Section 6 (uncertainty quantification and reporting)

verifier.accreditation: "ISO 14065" → ISO 14065:2020 (verification body competence)

measurer.accreditation: "ISO 17025" → ISO 17025:2017 (measurement laboratory competence)

standards[].standard.name: "ISO 14064-3:2019" + verificationStatement → ISO 14064-3:2019 (verification opinion requirements)

gwpBasis: "IPCC AR5 100-year" → ISO 14067:2018 + ISO 14064-3:2019 (GWP normalization basis)

This direct traceability from schema field to ISO requirement is what makes QET tokens audit-ready for ISO 14064-3 verification, CSRD assurance, and EU Methane Regulation MRV equivalence assessments.

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Verification Roles and Accreditation Requirements

The QET framework distinguishes three separate roles in the production and validation of a QET token, each governed by a different ISO standard:

The Producer is the LNG facility, natural gas producer, or RNG developer that generates the underlying emissions data and is responsible for accurate reporting. The producer implements the quantification methodology per ISO 6338:2023 (for LNG) or the EarnDLT QET core methodology (for NG and RNG).

The Measurer is the organization that conducts direct GHG measurements and provides the measurement data used in CI calculations. Measurement organizations must operate under an ISO 17025-accredited quality management system. This ensures that gas analyzers are calibrated to traceable standards, sampling procedures are documented, and measurement uncertainty is properly characterized.

The Verifier is the independent third party that issues the verification opinion on the QET token's environmental attributes. Verifiers must be accredited under ISO 14065:2020 and conduct verification engagements under ISO 14064-3:2019. For QET-LNG, verifiers must additionally demonstrate competence in LNG plant operations, refrigeration systems, and BOG management per Section 8.2 of the QET-LNG methodology.

This three-role structure prevents a single organization from both producing and verifying its own data — a structural safeguard that mirrors the requirements of regulated environmental markets including the EU ETS.

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Frequently Asked Questions

Is ISO 6338:2023 required for all QET-LNG tokens, or only for certain markets?
ISO 6338:2023 is required for all QET-LNG tokens regardless of the buyer's jurisdiction. It is the normative quantification standard specified in the QET-LNG methodology document and cannot be substituted with facility-specific or national methodologies. Facilities that currently quantify LNG plant emissions under a different methodology (e.g., API LNG GHG methodology) must demonstrate equivalence with ISO 6338:2023 or recalculate using the ISO 6338 framework.

What happens when an LNG plant produces LPG, condensate, and power in addition to LNG — how does ISO 14044 allocation work in practice?
The ISO 14044 hierarchy requires that the QET-LNG methodology first attempt energy content allocation: total facility emissions are multiplied by the ratio of LNG energy output (HHV basis) to total facility energy output across all products. If a plant produces 22.9M MMBtu of LNG, 0.23M MMBtu of LPG, and 0.13M MMBtu of condensate, the LNG allocation factor would be approximately 0.946 — meaning 94.6% of total facility emissions are attributed to LNG. This factor is disclosed in every QET-LNG token and is subject to independent verification under ISO 14064-3.

Why does ISO 6976 matter — can't heating values just be estimated from composition?
ISO 6976 is not just about estimation — it specifies the calculation method itself, including which reference conditions (temperature, pressure) apply and how mixture heating values are computed from component values. An LNG facility with an average heating value of 55 MMBtu/tonne that imprecisely uses 54 MMBtu/tonne introduces a ~1.8% systematic error in every CI calculation. At 8 million tonnes annual production, that represents a meaningful misstatement. ISO 6976 compliance, with regular compositional analysis and traceable calculation methods, eliminates this class of error.

What is the difference between ISO 14064-3 and ISO 14065 — aren't they both "verification standards"?
ISO 14064-3 specifies how verification is conducted: the principles, evidence requirements, and opinion types. ISO 14065 specifies who can conduct verification: the organizational competence, impartiality requirements, and quality management systems that a verification body must have. A verifier can technically follow ISO 14064-3 procedures without being ISO 14065 accredited — but this provides much weaker assurance. EarnDLT requires both: ISO 14064-3 governs the engagement, and ISO 14065 accreditation qualifies the organization conducting it.

Is ISO 17025 accreditation required for all data inputs, or only direct measurement campaigns?
ISO 17025 accreditation is required for measurement organizations conducting the direct GHG measurements and analytical services that serve as primary data inputs under QET Section 6.1. It is not required for the LNG facility's own operational data collection (fuel gas consumption logs, production meters, etc.) — those are governed by the QET data quality and calibration requirements in Section 6.3. However, calibration of custody transfer meters and gas analyzers must be traceable to national standards consistent with ISO 17025 principles even when conducted in-house.

Does QET-NG or QET-RNG have different ISO standard requirements than QET-LNG?
The core verification and footprinting stack — ISO 14064-3, ISO 14067, ISO 14044, ISO 14065, ISO 17025 — applies identically across all QET types. The primary difference is the quantification standard: QET-LNG uses ISO 6338:2023 as its LNG-specific plant calculation methodology, while QET-NG and QET-RNG reference the EarnDLT QET core methodology (aligned with ISO 14067) supplemented by segment-specific quantification guidance. ISO 6976 applies to all three token types wherever natural gas heating values must be determined from compositional analysis.