EN 13432 vs ASTM D6400 vs OK Compost: which do you need?
Compostable certification is the easiest place in packaging to be misled, because the certificates look interchangeable and are not. The differences that matter are the market that accepts them, the disposal environment they cover, and a thickness limit that most buyers never read.
Almost every compostability scheme in the world traces back to one of two documents.
The two base standards
EN 13432 is the European standard for packaging recoverable through composting and biodegradation. It sets four requirements: disintegration within twelve weeks, biodegradation of at least 90% within six months, heavy-metal and fluorine limits, and no negative effect on compost quality as shown by plant-growth testing.
ASTM D6400 is the North American equivalent, specifying plastics designed to compost in municipal and industrial aerobic facilities. The thresholds are close enough to EN 13432 that products generally pass both, but the two are separately assessed and separately certified.
Both describe industrial composting: sustained elevated temperature, controlled moisture, managed aeration. Neither is a claim about a garden compost heap, and neither is a claim about what happens in landfill or in the sea.
Standards are documents. Marks are what appears on your artwork, and each is issued by a specific body against a specific standard.
The certification marks buyers actually recognise
- Seedling — European mark for industrial compostability, conformity assessed against EN 13432.
- OK Compost INDUSTRIAL (TÜV) — conformity with EN 13432 for industrial composting. OK Compost HOME is a separate, materially harder certification covering ambient-temperature garden composting.
- BPI — the North American certification mark, based on ASTM D6400, and the one US municipal composters and retailers ask for by name.
- ABAP — the Australasian home-compostable scheme, effectively the entry ticket for the Australian and New Zealand markets.
Choose by destination market, not by which certificate your supplier happens to hold. A Seedling logo does not satisfy a US composter asking for BPI, and BPI does not answer a European retailer's EN 13432 question.
Industrial composting runs hot. Home composting does not — it is ambient, uneven, often anaerobic in patches, and slow.
Home compostable is a different product, not a better badge
A film certified for industrial composting will frequently not break down in a garden heap within any reasonable period. Home-compostable certification therefore requires a different formulation and, critically, a much thinner film.
This is where compostable claims most often fall apart on inspection: every compostability certificate names a maximum film thickness. Certification is granted for a material at a gauge, not for a product family in the abstract. As a rule of thumb across the schemes we hold, home compostable caps around 60–63 µm, industrial compostability runs roughly 61–140 µm, and BPI extends to about 143 µm.
If your specification sits above the certified thickness, the certificate does not cover it. A supplier who quotes a heavy-gauge compostable bag against a thin-gauge certificate is selling you a claim that fails the first time a customer's compliance team reads the scope.
What to ask your supplier
- Which certificate covers this exact product — not the range, the item.
- What is the certified thickness range, and where does my specification sit inside it?
- Does the certificate cover the resin, the film, or the finished bag? Full-chain coverage across all three lets a supplier certify a custom structure rather than only a catalogue item.
- What is the expiry date, and when is recertification due?
- Can I have the certificate now? Certificates are screening documents. Any supplier treating them as confidential is worth a second look.
We hold EN 13432 certification directly at the Henan production base, ASTM D6400 through BPI across resin, film and finished bag, plus OK Compost and ABAP home-compostable coverage — and we state the certified thickness range with every compostable quotation. See the certification list.
Common questions
Is EN 13432 the same as ASTM D6400?
They are closely aligned but separate. EN 13432 is the European standard and ASTM D6400 the North American one. Products generally pass both, but each is separately assessed and separately certified — holding one does not give you the other.
Does industrial compostable certification mean it will break down in my garden compost?
No. Industrial composting uses sustained elevated temperature and controlled conditions that a garden heap does not reach. Home composting requires separate certification such as OK Compost HOME or ABAP, a different formulation and a thinner film.
Why does a compostable certificate specify a maximum thickness?
Because disintegration depends on gauge. Certification is granted for a material at a stated thickness, so a heavier-gauge version of the same film is outside the certificate's scope. Home compostable typically caps around 60–63 µm, industrial around 61–140 µm and BPI around 143 µm.
Where to go next
We answer every enquiry within 12 hours and issue a detailed quotation within 24 hours. Send us a specification.