How to Verify a Biochar Producer’s Quality Claims: A Procurement Officer’s Checklist

Why “certified” is not enough

It is common to see a biochar producer display a heading like “Certifications” with no specific certificate named beneath it, no standard ID, and no number you can look up. Treat that as the absence of a verifiable claim. A real certification has three components you can independently confirm: a named standard, a named certifying body, and a certificate or registry number that resolves in a public database. If any of the three is missing, the claim is not procurement-grade.

Lab tests to require

Require a recent, third-party, per-batch lab report covering at least:

• Fixed carbon content and the hydrogen-to-organic-carbon (H/Corg) molar ratio, the core stability and quality indicators in IBI and EBC standards.
• BET surface area (test method ASTM D6556) for any filtration application.
• Polycyclic aromatic hydrocarbons (PAH), which form during pyrolysis and must fall under the limits set by the governing standard.
• Heavy metals, especially for soil and water applications where the char’s contaminants transfer to the environment.
• Ash content and pH, which affect performance in soil and filler applications.

A one-time “type test” from years ago is not the same as a per-batch report. Require the latter for ongoing supply.

Certificates to confirm

Match the producer’s claimed certification to the right public database and confirm the number resolves:

• IBI Biochar Standards quality certification.
• EBC (European Biochar Certificate) grade.
• Puro.earth methodology, with a marketplace and registry record for carbon credits.
• Carbon Standards International (CSI) Artisan or Industrial C-Sink for carbon credits.
• USDA BioPreferred registry for biobased-content claims.

If a producer claims a carbon credit, confirm the registry serial number and the retirement record, not just a logo.

Site and process due diligence

For ongoing or large-volume supply, go beyond paper:

• Pyrolysis process type. Slow pyrolysis maximizes biochar quality and yield; gasification minimizes it. Confirm the process matches your grade.
• Feedstock receipts and chain of custody, mandatory for any carbon claim.
• A documented quality plan with batch traceability, so a failed batch can be isolated.

Red flags

Treat these as signals to ask harder questions or walk:

• A “certifications” claim with no named standard or number.
• Quote-only pricing with no published specification at all.
• No life-cycle assessment (LCA) for a producer making a carbon or sustainability claim.
• No per-batch lab reports, only a single historical type test.
• Reluctance to provide a certificate number you can verify independently.

None of these is automatically disqualifying on its own, but each one shifts the burden of proof back onto the buyer, and a producer who cannot supply documentation is a producer whose claims you cannot stand behind.

How ECS helps

ECS is a vendor-neutral routing partner. We run this verification as standard practice: we collect the per-batch lab reports, confirm every certificate number against the public databases, and check the registry record for any carbon claim before a producer enters your bid set. You receive bids you can defend in an audit, not brochures.

Request a quote with your application and volume, and we will verify the field for you.