Global Biochar C-Sink Standard introduces Upper Persistence Class

Dear Sir or Madam,

effective June 9, 2026, Version 3.3 of the Global Biochar C-Sink Standard enters into force.

The key update is the introduction of an Upper Persistence Class for biochar.

New quality tier for highly persistent biochar

Where appropriate HyPy or Random Reflectance measurements are available, biochar may be assigned to the Upper Persistence Class. In this case, 90% of the contained carbon is recognised as stably stored for at least 1,000 years.

The Upper Persistence Class combines decades of experience in biochar quality assessment with modern analytical methods for determining carbon stability. The classification is based on a scientifically grounded assessment framework within the Global Biochar C-Sink Standard, which uses the EBC certification as a quality foundation and extends it with HyPy and Random Reflectance analyses for assessing carbon stability.

This further differentiates the assessment of high-quality biochar and integrates current scientific understanding from international biochar research into the standard.

Public consultation results

We would like to sincerely thank all participants in the public consultation for their valuable input and constructive feedback.

The submitted comments and our responses are available here:

During the consultation, the updated version was originally announced as Version 4.0. As the core structure and existing project and monitoring requirements remain unchanged, the final release is published as Version 3.3. Additional topics raised during the consultation will be reviewed in the coming months and may inform the development of a future Version 4.0.

Further information

We informed Project developers and producers on June 3, 2026 about the operational implementation steps. For any questions or coordination regarding implementation, we remain available at any time and support the rollout of the new version in ongoing projects.

E-mail

Kind regards,

Robin Werren
PM Global Biochar C-Sink