Compostable Packaging Claims Substantiation FAQ
What evidence is required before calling packaging compostable?
A four-part test report against a recognized standard such as ASTM D6400 or EN 13432: biodegradation rate (typically 90 percent or more conversion within the test window), disintegration through a defined screen threshold, ecotoxicity (seedling survival and biomass), and heavy-metal limits. The report must cover the finished product — including inks, adhesives, and coatings — not just the base resin, and the evidence must exist before the claim appears on the pack. (Source: ASTM D6400, 2024)
What is the difference between 'biodegradable' and 'compostable' on a label?
'Compostable' names a defined environment and a test standard — industrial composting at specified conditions verified against ASTM D6400 or EN 13432. Unqualified 'biodegradable' promises degradation with no environment, timeframe, or standard attached, which is why regulators treat it as an indefensible general claim. If your package passes the standard, write 'compostable in industrial facilities' and let the certification mark carry the rest. (Source: U.S. FTC Green Guides, 2024)
Which certification marks should a brand look for?
The two widely recognized programs are BPI certification in North America, backed by ASTM D6400 for industrial compostability, and TÜV Austria's OK compost marks — OK compost INDUSTRIAL under EN 13432 and OK compost HOME for backyard composting. Certificates are product-specific and renew periodically, so verify the certificate number covers the exact SKU and formulation you ship and remains current. (Source: BPI, 2025; TÜV Austria, 2025)
What label wording is defensible for a compostable package?
Mirror the certificate: same environment, same program, same SKU. 'Certified compostable (BPI)' is defensible when the certificate covers the SKU; 'compostable in industrial facilities' is defensible with a D6400 or EN 13432 pass; 'home compostable' requires a home-composting certificate such as OK compost HOME. Avoid unqualified 'compostable' where readers could assume backyard bins, and never print '100% compostable' unless every layer — inks and adhesives included — is certified.
How is a certificate affected by a formulation change?
A formulation change ends the certificate's validity for that SKU. Changing an ink, thinning a coating, or switching an adhesive means the product on the shelf is no longer the product that was tested, and the claim must be re-verified before the revised product ships. Treat formulation changes as claim events, not production events, and keep them on the same calendar as certificate renewals.
What should a compostable claim substantiation file contain?
Five elements: the four-part test reports naming the tested formulation and date; current certificates from BPI or TÜV Austria matching each SKU; supplier declarations for resin, ink, adhesive, and coating flowing upstream; a label-copy register mapping every published claim to its evidence and date; and a renewal calendar covering certificate expiry, formulation-change reviews, and re-test triggers. Regulatory guidance requires environmental claims to be substantiated with competent and reliable evidence, so the file — not the adjective — is what survives a challenge. (Source: U.S. FTC, 2024)
Do EU rules add requirements for compostable packaging claims?
Yes. In the EU, compostability claims for packaging sit inside the PPWR framework, which ties packaging-related claims to defined technical baselines, and the EU-wide rules on green claims require substantiation and verification of explicit environmental claims. A package sold in the EU should be certified to EN 13432 or the applicable EU compostability criteria, with the evidence file structured so the same documentation serves both the claim and the compliance record. (Source: European Commission PPWR, 2024)