Chapter 07 · Materials & footprintsCircular Economy & Materials
Compostable
Definition
'Compostable' means a material meets test-standard requirements to biodegrade, disintegrate and leave non-toxic compost: under EN 13432 (EU) and ASTM D6400/D6868 (US), at least 90% of the material must biodegrade within six months, fragments must pass a 2 mm sieve after twelve weeks, and limits apply to heavy metals and ecotoxicity. These standards assume industrial composting at 55–70°C; separate schemes (e.g. OK Compost HOME, AS 5810) certify home compostability.
References
Product must break down in a timely way in home compost; qualify if municipal facilities limited
FTC Green Guides16 CFR 260.7 · verified 2026-08-22Official text
EN 13432 requirements; certification marks
EN 13432/ASTM D6400 landscape; composting conditions
industrial versus home composting standards
Overview
What it means
Compostable is a narrower, certified claim than 'biodegradable', which has no fixed timeframe or conditions.
How it is used
In the EU, packaging may only be marketed as compostable if it conforms to EN 13432; certification marks (Seedling logo, BPI) signal conformity.
Why it matters
Compostables work only where collection and industrial composting exist; sent to landfill or nature, they persist — a standing greenwashing and contamination risk.