Understanding Bioplastics Standards and Certifications
Bioplastics standards and certifications are formal frameworks that verify whether a material meets specific criteria for biodegradability, compostability, or bio-based content. These standards — including EN 13432, ASTM D6400, and certifications from TUV Austria — protect consumers from greenwashing and give manufacturers a credible way to demonstrate their products’ environmental credentials. Without them, claims like “compostable” or “biodegradable” would remain unverifiable marketing language.
As the bioplastics market continues to grow, the role of standards and certifications has become increasingly critical. They serve as the bridge between laboratory science and real-world performance, ensuring that materials labeled as compostable actually break down under defined conditions, and that bio-based claims are backed by measurable evidence. This guide covers the major international standards, the certification bodies that enforce them, and what each label means in practice.
Why Standards Matter for Bioplastics
Standards matter because they establish objective, repeatable criteria for evaluating bioplastic materials. Without standardized testing protocols, any manufacturer could label a product as “biodegradable” regardless of how it actually performs in soil, water, or composting facilities. Standards define the specific temperature, timeframe, and disintegration thresholds a material must meet to earn a given classification.
For the broader bioplastics industry, standards serve several essential functions:
- Consumer protection — Buyers can trust that certified products meet defined performance criteria rather than relying on vague marketing claims.
- Regulatory compliance — Many jurisdictions now require compostability certifications before products can be marketed as compostable or accepted in organic waste streams.
- Waste management alignment — Composting facility operators need assurance that incoming materials will fully biodegrade within their processing cycles.
- Market access — Retailers and brand owners increasingly require third-party certification as a condition of procurement.
- Innovation benchmarking — Standards give material developers clear targets for product performance during R&D.
Major International Standards for Compostability
Several key standards govern the testing and verification of biodegradable and compostable bioplastics. Each standard was developed for a specific regional or industrial context, but they share a common scientific foundation rooted in controlled biodegradation testing.
EN 13432 — European Standard for Packaging Compostability
EN 13432 is the primary European standard for determining whether packaging materials are compostable in industrial composting facilities. Published by the European Committee for Standardization (CEN), it is the harmonized standard under the EU Packaging and Packaging Waste Directive. A material must satisfy all four of the following criteria to pass EN 13432:
| Criterion | Requirement | Test Method |
|---|---|---|
| Chemical Composition | Heavy metals and fluorine below defined thresholds; volatile solids content above 50% | Chemical analysis per EN 13432 Annex A |
| Biodegradation | At least 90% conversion to CO₂ within 6 months under controlled composting conditions | ISO 14855 (CO₂ evolution method) |
| Disintegration | At least 90% of material passes through a 2 mm sieve after 12 weeks of composting | ISO 16929 (pilot-scale composting test) |
| Ecotoxicity | No negative effect on plant germination or biomass yield in compost-amended soil | OECD 208 (terrestrial plant test) |
EN 13432 is widely regarded as one of the most rigorous compostability standards in the world. It specifically applies to industrial composting conditions (temperatures of 58°C ± 2°C), not home composting. Materials that pass EN 13432 can carry the Seedling logo, which is discussed in detail below.
ASTM D6400 — North American Standard for Compostable Plastics
ASTM D6400 is the standard specification for labeling plastics designed to be aerobically composted in municipal or industrial facilities. Developed by ASTM International (formerly the American Society for Testing and Materials), it is the primary compostability standard used in the United States and Canada.
ASTM D6400 requires materials to meet three key performance thresholds:
- Biodegradation — 60% conversion to CO₂ within 180 days for homopolymers, or 90% for copolymers and blends (tested per ASTM D5338).
- Disintegration — Less than 10% of the original dry weight remains on a 2 mm sieve after 12 weeks of composting.
- Ecotoxicity — No adverse effect on plant growth when compost containing the test material is compared to a control, tested at concentrations relevant to real-world composting.
While ASTM D6400 and EN 13432 are broadly comparable, there are subtle differences in biodegradation thresholds and testing protocols. Products intended for both European and North American markets typically undergo testing against both standards.
ASTM D6868 — Standard for Compostable Coatings and Substrates
ASTM D6868 specifically addresses items where a biodegradable plastic coating or additive is applied to a compostable substrate, such as paper cups lined with PLA. It shares the same fundamental testing approach as ASTM D6400 but applies to composite products rather than standalone plastic items. This is particularly relevant for bioplastic packaging applications that combine multiple material layers.
ISO 17088 — International Standard for Compostable Plastics
ISO 17088 is the international equivalent, providing specifications for plastics suitable for recovery through aerobic composting. Published by the International Organization for Standardization, it aligns closely with both EN 13432 and ASTM D6400, serving as a harmonizing framework. Many national standards reference ISO 17088 as their foundation.
Certification Bodies and Logos
While standards define what a material must achieve, certification bodies are the organizations that verify compliance through independent laboratory testing and ongoing auditing. Several major certification bodies operate globally, each issuing recognizable logos that appear on certified products.
TUV Austria Certifications (formerly Vinçotte)
TUV Austria (which acquired Belgian certification body Vinçotte) is one of the most prominent certifiers of bioplastics worldwide. TUV Austria offers a comprehensive portfolio of certification schemes that cover scenarios beyond just industrial composting:
| Certification | What It Verifies | Key Conditions |
|---|---|---|
| OK Compost INDUSTRIAL | Compostability in industrial composting plants | Based on EN 13432; temperatures ~58°C |
| OK Compost HOME | Compostability in home compost bins | Lower temperatures (~20–30°C); longer timeframe |
| OK Biodegradable SOIL | Biodegradation in natural soil | Relevant for agricultural films and mulch products |
| OK Biodegradable WATER | Biodegradation in freshwater environments | Tests conducted at ambient water temperatures |
| OK Biodegradable MARINE | Biodegradation in marine/saltwater environments | The most demanding biodegradation environment |
| OK Biobased | Bio-based carbon content of the product | Star rating system (1–4 stars based on % bio-based content) |
The distinction between OK Compost INDUSTRIAL and OK Compost HOME is particularly important. Industrial composting facilities operate at sustained high temperatures (55–60°C) with controlled moisture and aeration. Home composting environments are far more variable, with lower temperatures and less consistent conditions. A material that biodegrades reliably at 58°C may not break down adequately in a backyard compost heap at 25°C. The OK Compost HOME certification addresses this gap, applying stricter criteria to ensure materials genuinely biodegrade under less controlled conditions.
The OK Biobased certification is distinct from compostability certifications. It measures what percentage of a product’s carbon is derived from renewable, biological sources rather than fossil fuels. This is relevant for bio-based polymers that may or may not be biodegradable — for example, bio-based PET is derived from renewable feedstock but is chemically identical to conventional PET and is not biodegradable.
The Seedling Logo (European Bioplastics / DIN CERTCO)
The Seedling logo is one of the most widely recognized symbols for industrially compostable packaging in Europe. It is administered by European Bioplastics in cooperation with DIN CERTCO, a subsidiary of TUV Rheinland. The Seedling logo signifies that a product has been independently tested and certified to conform to EN 13432.
When consumers or waste management operators see the Seedling logo, they can be confident that:
- The product will biodegrade by at least 90% within 6 months under industrial composting conditions.
- The product will physically disintegrate within 12 weeks in a composting environment.
- The resulting compost will not be toxic to plants or the soil ecosystem.
- The material does not contain harmful levels of heavy metals or other regulated substances.
The Seedling logo has been adopted by several European countries as part of their waste labeling systems. In Italy, for example, compostable packaging bearing the Seedling logo is accepted in organic waste collection bins.
BPI Certification (Biodegradable Products Institute)
The Biodegradable Products Institute (BPI) is the leading certification body for compostable products in North America. BPI certification verifies that products meet ASTM D6400 or ASTM D6868. BPI-certified products are listed in a publicly searchable database, and the certification requires periodic re-testing and facility audits to maintain validity.
BPI certification has become a de facto requirement for products marketed as compostable in the United States and Canada, and many composting facilities only accept items that carry the BPI logo.
Standards for Bio-Based Content
Bio-based content standards measure the proportion of a material that is derived from renewable biological resources, as opposed to fossil-based sources. It is essential to understand that bio-based content and biodegradability are independent properties — a product can be 100% bio-based but non-biodegradable, or fully biodegradable but derived from fossil sources.
ASTM D6866 — Bio-Based Content Determination
ASTM D6866 uses radiocarbon (Carbon-14) analysis to determine the bio-based carbon content of a material. Because fossil-derived carbon has a different C-14 signature than recently fixed biological carbon, this method can precisely quantify the percentage of carbon in a product that comes from biomass versus petroleum. This standard is the foundation for bio-based labeling programs in both Europe and North America.
EN 16785 — European Bio-Based Content Standard
EN 16785 provides the European methodology for determining bio-based content. Part 1 covers the radiocarbon method (similar to ASTM D6866), while Part 2 addresses bio-based content determination using elemental analysis, particularly for products containing nitrogen, hydrogen, or oxygen from bio-based sources that would not be captured by carbon-only methods.
Biodegradability Standards Beyond Composting
Not all biodegradable bioplastics are designed for composting facilities. Some applications require materials that biodegrade in soil, freshwater, or marine environments. Each scenario demands different testing conditions, and several specialized standards address these end-of-life pathways.
| Environment | Standard | Key Conditions |
|---|---|---|
| Industrial composting | EN 13432 / ASTM D6400 | 58°C, controlled humidity, 6 months |
| Home composting | AS 5810 (Australia) / NF T51-800 (France) | Ambient temperature, 12 months |
| Soil biodegradation | EN 17033 | Soil burial, ambient temperature, 24 months |
| Freshwater biodegradation | ISO 14851 / ISO 14852 | Aqueous aerobic conditions, ambient temperature |
| Marine biodegradation | ASTM D7081 (withdrawn) / ISO 22766 | Seawater conditions, ambient temperature |
| Anaerobic digestion | ISO 15985 | Anaerobic conditions, 52°C |
The standard EN 17033 is particularly important for agricultural applications such as biodegradable mulch films. It defines requirements for plastic mulch films that biodegrade in soil, helping farmers avoid the labor and cost of removing conventional plastic mulch after the growing season. This standard is relevant to understanding which bio-based materials are not biodegradable and therefore not suitable for soil-degradation applications.
How to Read and Verify Certification Labels
When evaluating a bioplastic product’s certifications, look for the following elements on the label or packaging:
- Certification logo — A recognized mark such as the Seedling, BPI, or TUV Austria OK Compost logo.
- Certificate number — A unique identifier that can be verified on the certifying body’s website or public database.
- Standard reference — The specific standard the product is certified against (e.g., EN 13432 or ASTM D6400).
- Scope of certification — Whether the certification covers the entire product or only specific components (e.g., the film but not the adhesive label).
Be cautious of products that use terms like “biodegradable” or “eco-friendly” without referencing a specific standard or displaying a recognized certification logo. Such claims may not be supported by independent testing. The distinction between certified compostable and merely “biodegradable” is significant — learn more about biodegradable fossil-based polymers and how their end-of-life performance varies.
The Future of Bioplastics Standards
The standards landscape for bioplastics continues to evolve. Several developments are shaping the future of certification and testing:
- Microplastic formation — New research is prompting standard-setting bodies to consider whether certified compostable materials leave behind microplastic residues, even if they meet current disintegration thresholds.
- Home composting harmonization — There is growing demand for a unified international standard for home compostability, as current home composting standards vary by country.
- Digital certification — QR codes and digital product passports are being integrated with certification schemes, allowing consumers and waste sorters to instantly verify a product’s compostability credentials.
- PFAS exclusion — Certification bodies, including BPI, have updated their requirements to exclude products containing per- and polyfluoroalkyl substances (PFAS), even if those products otherwise meet compostability criteria.
- EU regulatory alignment — The EU’s updated Packaging and Packaging Waste Regulation is expected to strengthen the role of EN 13432 and potentially mandate compostability certification for specific product categories like tea bags, coffee pods, and fruit stickers.
For a broader understanding of how these standards fit into the overall bioplastics landscape, explore the Knowledge Zone or read about non-biodegradable fossil-based polymers to understand what falls outside the scope of these certifications.