> For the complete documentation index, see [llms.txt](https://documentation.carbonregistry.com/documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.carbonregistry.com/documentation/icr-program/updates/august-2026-clarification.md). # August 2026 - Clarification Clarification on the Application of CDM Methodologies under the ICR Program
### Purpose and context ICR is providing this clarification to support consistent application of methodologies, modules, tools, methodological guidance and good practice guidance under the ICR Program, particularly in the context of the transition from the Clean Development Mechanism (CDM) to the Paris Agreement Crediting Mechanism (PACM). ### Transition from CDM to PACM ICR has historically provided blanket approval for active CDM methodologies and tools, subject in all cases to conformity with applicable ICR Program requirements and ISO 14064-2. The CDM methodological framework is now transitioning to the PACM. As part of this transition, methodologies and methodological tools are being reviewed, revised and, where appropriate, re-established under the PACM framework. A similar evolution has taken place within the ICR Program, which has undergone substantial development since its establishment and has progressively strengthened its requirements with reference to evolving international integrity expectations, including the ICVCM Core Carbon Principles and the ICAO CORSIA Emissions Unit Criteria. Going forward, active PACM methodologies and tools are approved for application under the ICR Program, subject to their applicability conditions and conformity with applicable ICR Program requirements and ISO 14064-2. Where a methodology or tool exists under both the CDM and PACM, the applicable PACM methodology or tool supersedes the corresponding CDM methodology or tool for application under the ICR Program. The PACM methodological framework continues to develop, and the transition of the extensive CDM methodological portfolio remains ongoing. Consequently, there may be project activities for which no directly corresponding or applicable PACM methodology or methodological tool is yet available. In such circumstances, relevant active CDM methodologies and tools may continue to provide an important source of established methodological practice, subject to their application in accordance with current ICR Program requirements as further clarified below. Accordingly, the application of CDM methodologies and tools under the ICR Program should be considered in the context of subsequent methodological developments under the PACM and the evolution of ICR Program requirements, which may introduce updated criteria, approaches or implementation expectations alongside the established CDM methodological framework. To support this transition, ICR established a transitional arrangement for projects applying CDM methodologies. Projects applying a CDM methodology were required to be pre-registered with ICR by 30 June 2026 and are required to complete validation by 31 December 2026. This transitional arrangement does not prevent relevant CDM methodological material from continuing to inform project design after the transition date. Rather, its status and application under the ICR Program changes as described below. For purposes of this clarification, an active CDM methodology means the applicable version of a methodology listed as active under the UNFCCC Clean Development Mechanism. ### Active CDM methodologies as good practice guidance Section 5.5 of the ICR Process Requirements v6.3 allows project proponents to apply, among other applicable criteria: 1. methodologies, modules, tools or methodological guidance from another GHG program where specifically approved; 2. good practice guidance informed from other GHG programs and used to support project specific criteria and procedures; and 3. project specific criteria and procedures, where permitted under the ICR Requirement Document and assessed through validation for the relevant project. Consistent with this framework, **through this clarification, ICR recognizes active CDM methodologies as acceptable sources of good practice guidance under Section 5.5 where they are relevant and fit for purpose.** Active CDM methodologies represent an extensive body of established methodological experience concerning baseline determination, additionality, project boundaries, identification of GHG SSRs, quantification, monitoring, leakage and other project design matters. Their technical content may therefore provide an appropriate basis for developing project specific criteria and procedures. However, reliance on an active CDM methodology as good practice guidance does not, by itself, constitute application of an ICR approved methodology. Where an active CDM methodology is relied upon as good practice guidance, the applicable criteria for the project comprise the resulting project specific criteria and procedures together with ISO 14064-2, applicable ICR Program requirements and any other applicable criteria identified under Section 5.5. ### Application of project specific criteria and procedures The application of a CDM methodology as good practice guidance should not be understood as applying the CDM methodology and its underlying CDM rules and methodological requirements without further consideration. The project proponent needs to identify the relevant provisions of the CDM methodology relied upon and clearly describe the criteria and procedures actually applied to the project. As applicable to the project activity, these shall consider: * applicability conditions; * baseline scenario and baseline determination; * additionality; * project boundary and identification and selection of relevant GHG SSRs; * quantification of GHG emission mitigations; * monitoring; * leakage; * uncertainty and conservativeness; * non-permanence and reversals, where applicable; * environmental and socio-economic safeguards; and * other applicable project design requirements. The resulting project specific criteria and procedures shall demonstrate conformity with ISO 14064-2, the current ICR Requirement Document, the ICR Process Requirements, the ICR Additionality Specifications and other applicable ICR Program requirements. Where a provision, procedure or criterion contained in the CDM methodology is inconsistent with, less stringent than, or does not adequately address an applicable ICR requirement, the applicable ICR requirement prevails unless ICR expressly specifies otherwise. ### Relationship with PACM methodologies, modules and tools Project proponents should also account for the continuing transition of methodological approaches from the CDM to the PACM. Where an active CDM methodology has subsequently been re-established or replaced by an applicable PACM methodology, the PACM methodology represents the current methodological framework recognized by ICR and should be applied in accordance with its applicability conditions. Similarly, where a CDM methodology refers to a CDM module, tool or methodological approach for which a corresponding PACM methodology, module or tool has subsequently been approved, the project proponent shall identify and consider the current PACM methodology, module or tool. Where the PACM module, tool or methodological approach is applicable to the project and supersedes the corresponding CDM methodology, module or tool, the current PACM methodology, module or tool shall be applied unless otherwise accepted by ICR. This is consistent with the supersession provisions in the ICR Approved Methodologies, Modules and Tools, under which PACM methodologies and tools supersede corresponding CDM methodologies and tools where applicable. This is particularly relevant where PACM tools establish updated requirements or procedures for matters such as additionality, baseline setting, common practice, investment analysis or other methodological functions. The existence of a PACM methodology, module or tool does not extend its applicability beyond its stated applicability conditions. Where a corresponding PACM methodology, module or tool is not applicable to the particular project circumstances, the project proponent needs to document the basis for that conclusion and justify the alternative criteria and procedures applied. ### Documentation and transparency Where an active CDM methodology is materially relied upon as good practice guidance, the project documentation shall provide sufficient information for the applied approach to be transparent, reproducible and independently assessed. The project proponent should clearly identify: 1. the active CDM methodology, modules and tools relied upon; 2. the provisions used as good practice guidance; 3. any corresponding PACM methodologies, modules or tools considered; 4. which CDM provisions or tools have been retained, adapted, supplemented or replaced; 5. any additional project specific criteria or procedures introduced to demonstrate conformity with current ICR requirements; and 6. the justification for the resulting methodological approach. The project documentation should not describe the CDM methodology as an ICR approved methodology where it is being relied upon under the good practice guidance provisions of Section 5.5. ### Validation by the VVB The VVB shall assess the applied good practice guidance and the resulting project specific criteria and procedures in accordance with the ICR Validation and Verification Specifications, ISO 14064-3 and other applicable ICR Program requirements. Conformity with an active CDM methodology alone is therefore not sufficient to demonstrate conformity with the ICR Program. The VVB shall assess whether the criteria and procedures applied to the project are appropriate for the project circumstances and whether their application supports conformity with ISO 14064-2 and applicable ICR requirements. This assessment should include, as applicable, consideration of: * the relevance and fitness for purpose of the CDM methodology used as good practice guidance; * applicable developments under the PACM; * the scientific and technical basis of the applied criteria and procedures; * completeness and consistency of the resulting methodological approach; * conservativeness and the risk of overestimation; * uncertainty treatment; * traceability of data, assumptions, parameters and methodological choices; and * whether the criteria and procedures provide an adequate basis for monitoring and subsequent verification. A positive project validation opinion applies to the project specific criteria and procedures assessed as part of that validation engagement. It does not constitute approval of the underlying CDM methodology for general application under the ICR Program. ### Development of methodologies for general application Where a methodology developer intends to establish criteria and procedures for repeated application across multiple projects, including an approach materially based on or adapted from a CDM methodology, the appropriate pathway is the ICR Methodology Approval Process or, as applicable, establishment of the methodology under the PACM. A methodology approved under the ICR Methodology Approval Process, or established under the PACM and accepted by ICR for application under the ICR Program, may be applied in accordance with its applicability conditions and applicable ICR Program requirements. ### Existing transitional projects This clarification does not alter the transitional provisions applicable to projects using CDM methodologies that were pre-registered with ICR by 30 June 2026. Such projects remain subject to the applicable transition requirements, including completion of validation by 31 December 2026, and to all other applicable ICR Program requirements. ### Note on upcoming ICR Program document updates ICR recently concluded a public consultation on proposed revisions to its core program documents, including the ICR Requirement Document, ICR Methodology Requirements, ICR Methodology Approval Process and ICR Definitions. The proposed revisions are intended to further clarify and strengthen the application of methodologies, methodological guidance, good practice guidance and project-specific criteria and procedures under the ICR Program. ICR is currently reviewing stakeholder input and finalizing the updated documents. Once finalized, the updated documents will further make explicit and consistent across the relevant ICR Program documents the treatment of methodologies and methodological guidance, including the transition from blanket approval of CDM methodologies to their use as good practice guidance under the ICR Program. {% file src="/files/nciTjGTH7HdKGpp4yRxi" %}