BSI Flex 2007: v1.0:2025-07

You can download a DRM-free copy of the standard here.

Guide the future direction of greenhouse gas removal standards

BSI Flex 2007 v1.0 has been developed using the BSI Flex process, allowing it to evolve with new research, technological developments, and stakeholder needs. The first version is now open for public consultation, providing an opportunity for stakeholders to review the initial content and share feedback. All comments will be considered to help inform potential future standards that build on this BSI Flex.

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About the specification

BSI Flex 2007 v1.0 has been developed in response to the UK Government’s updated Greenhouse gas removals (GGR): Business model (December 2023), which emphasizes the need for high-integrity removals and consistent, transparent quantification of CO₂ removed from the atmosphere.

This specification provides a robust framework for measuring carbon removals from direct air carbon capture and storage (DACCS) projects. It aims to:

• support the advancement of engineered GGR technologies;
• provide direction for projects applying for revenue support under the UK GGR business model; and
• enhance confidence in carbon markets by contributing to addressing climate change and stimulating innovation in GGR technologies.

Developed with input from a wide range of expert stakeholders and sponsored by the Department for Energy Security and Net Zero (DESNZ), this document offers clear, practical direction to help standardize quantification in a complex and evolving field.

What does the standard cover?

This BSI Flex specifies requirements for quantifying net carbon removals from DACCS projects that capture CO₂ directly from ambient air using chemical separation methods and permanently store it in geological formations.

It sets out minimum quality thresholds that apply to:

• Ex-ante assessment – project planning and design stages;
• Ex post evaluation – ongoing performance monitoring, reporting, and verification.

The specification focuses on stationary installations designed to deliver high-concentration CO₂ removal and permanent storage.

Who is it for?

This BSI Flex is of use to:

• Stakeholders involved in establishing revenue support under the UK GGR business model or in other types of support schemes.
• Installation developers wishing to select methodologies from independent crediting programmes, and other entities for the purpose of originating carbon credits for sale in approved markets, or for other GHG accounting purposes.
• Stakeholders seeking guidance on methods for determining the amount of transferred CO₂, net removals or carbon credits that might result from DACCS projects.

It may also be of interest to:

• Independent crediting programmes and other assessment and crediting methodology developers.
• Those working to standardize GHG monitoring, reporting, verification (MRV), and accounting for DACCS projects.

Download a free copy of the standard here.