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This is the 5th blogpost of the ‘Upgrade to RSB – The Confidence to Lead’ series
To read the 1st blogpost, click here.
To read the 2nd blogpost, click here.
To read the 3rd blogpost, click here.
To read the 4th blogpost, click here.
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In the race to scale climate solutions, waste and residue feedstocks have emerged as critical pieces of the bioeconomy puzzle. From used cooking oil and animal fats to palm oil mill effluent and forest residues, these materials can appear to offer a compelling value proposition: use what already exists, reduce landfill and methane emissions, and create climate-friendly alternatives to fossil inputs.
But while waste-based feedstocks are often seen as ‘low-risk’, they are far from low-consequence. In a world of growing demand for low-carbon fuels and materials – driven by regulations like the EU’s RED III, ICAO CORSIA, and national SAF mandates – residues are no longer fringe. They are big business.
That makes credibility even more essential.
At the same time, no single feedstock – waste or otherwise – can deliver sustainable transformation at scale. Meeting decarbonisation goals in aviation, shipping, chemicals, and beyond will require a wide array of feedstocks, including wastes, residues, sustainably grown crops, and innovative inputs like renewable electricity and bio-based CO₂. What matters is not what the feedstock is, but whether the fuel that is made from that feedstock has a significantly lower GHG emission reduction and whether the feedstock is produced and verified in a sustainable, transparent, and trusted way.
RSB’s certification system is designed to address this challenge. In this post, we explore how RSB builds confidence in waste and residue-based supply chains that are certified against the EU Renewable Energy Directive (RED) and its other schemes, recognising both the value and the risks these materials carry.
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1. Sustainability risk analysis applied to each feedstock
RSB applies feedstock-specific sustainability risk analysis to ensure that certification requirements respond to each material’s real-world impacts. This assessment considers feedstock origin, production method, market dynamics, and the likelihood of environmental or social risks – such as land use change, biodiversity loss, water stress, and labour concerns.
Where higher risks are identified, RSB applies additional safeguards to strengthen the credibility of the certification outcome.
A key part of this approach is RSB’s displacement emissions methodology, which addresses situations where a waste feedstock is diverted from its original use, potentially triggering indirect environmental impacts. For example, when molasses is diverted from animal feed to biofuel production, the resulting demand for replacement feed could lead to increased crop production, land use, or emissions elsewhere. RSB’s methodology accounts for these indirect effects to ensure that GHG claims reflect true net reductions.
To illustrate how these safeguards are applied:
- Molasses is subject to mandatory displacement emissions analysis to assess and account for any indirect impacts.
- Palm-derived residues like palm oil mill effluent (POME), palm fatty acid distillate (PFAD) must be traceable to certified plantations, using RSB or an equivalent scheme aligned with RSB’s Principles & Criteria.
- Used cooking oil sourced from informal or decentralised markets may trigger enhanced traceability and physical sampling requirements.
This risk-responsive approach ensures that high-risk materials are met with high-integrity safeguards, while avoiding undue burdens for lower risk feedstocks.
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2. Enhanced oversight for higher-risk audits
In response to evolving challenges in the certification space, RSB has worked with its independent oversight body, SAJOMA Climate, to develop and implement additional measures for high-risk audits. These safeguards are designed to ensure that certification activities remain credible, especially in contexts where incentives, volume, or opacity create elevated risks of misrepresentation or non-compliance.
The additional measures include:
- Pre-surveillance audit reviews: For operators handling high-risk materials, SAJOMA and RSB jointly review audit documentation prior to surveillance audits to ensure sufficient depth and focus.
- Triggered witness audits: In cases where high-risk materials are being  certified for the first time, or where specific risks are identified in the audit plan, RSB may require that SAJOMA or a designated technical expert observe the audit in real time.
- Audit plan scrutiny: When high-risk conditions are identified, Certification Bodies (CBs) are required to submit their audit plans for review by SAJOMA. This ensures that site visits, sampling strategies, and plausibility checks are appropriately scoped and proportionate to the level of risk.
- Systematic performance review of CBs: SAJOMA conducts ongoing assessments of CB performance with a focus on high-risk supply chains, issuing guidance and follow-ups where performance issues or inconsistencies are found.
These additional layers of oversight enable RSB to ensure that its assurance system continues to meet high standards of technical credibility, even as pressure and complexity in the marketplace increase. Rather than relying solely on standard audit cycles, this approach reflects a dynamic, responsive model of risk-based oversight.
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3. Surveillance audits for those working with wastes and residues
RSB applies enhanced scrutiny to supply chains that handle waste and residues. Any Participating Operator (PO) that trades or processes these materials is subject to a surveillance audit within six months of their initial certification audit. Where first collectors or traders within an EU RED supply chain include both virgin and residue-based materials, an additional audit must be completed within three months of their initial certification audit.
RSB’s emphasis on early-stage due diligence helps identify, assess, and mitigate potential risks across supply chains and sourcing areas — before the verification audit takes place. This proactive approach strengthens the credibility of the RSB system while ensuring compliance remains practical and proportionate for operators.
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4. Public transparency and stakeholder consultation
Transparency in certification isn’t just about publishing reports; it’s about creating meaningful visibility and accountability throughout the process. RSB integrates transparency at multiple stages of the certification process, including both public reporting and structured stakeholder engagement.
All RSB certification applications trigger a public stakeholder consultation period, announced via the RSB website. This consultation:
- Is open for a minimum of 14 days.
- Invites input from affected communities, NGOs, industry peers, and any other interested parties.
- Occurs prior to certification, giving stakeholders a formal opportunity to raise concerns or provide additional context.
When critical information is received, for example, sustainability risks, auditors are required to follow up, paying special attention to those areas of concern at the audit. This may include revisiting sites, requesting additional evidence, or re-evaluating aspects of the audit.
In addition to stakeholder input, RSB audit reports – including those covering waste and residue supply chains – are published in summary form. These summaries include:
- The types  of materials certified
- Number of sites certified and their location
- Key findings and non-conformities
- The outcome of risk assessments and site inspections
This level of transparency is intentional and reflects RSB’s commitment to openness and accountability. It enables market actors, regulators, and the public to verify claims, monitor performance, and engage meaningfully with the certification process.
Transparency is built into the system, not bolted on.
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5. Clear requirements for palm-derived residues
Palm-derived materials – such as POME, PFAD, palm glycerin, and acid oils – are often treated as residues, but they can carry many of the same risks as virgin palm oil, especially where land use, biodiversity, or human rights issues are involved.
RSB requires that palm-derived production residues be traceable to certified plantations, either through RSB certification or an equivalent scheme aligned with the environmental and social safeguards of RSB’s Principles & Criteria. This ensures that even when a material is technically classified as a residue, its origin is still subject to robust sustainability requirements, including verification at the sourcing area.
This additional requirement helps prevent palm residues from being used as a ‘back door’ to bypass sustainability safeguards, reflecting RSB’s commitment to proactively addressing risks associated with the palm oil industry.
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6. Preventing fraud and misclassification
The rapid growth in demand for waste and residue-based feedstocks – particularly in regulated markets that offer financial or compliance incentives – has created strong economic drivers. In some cases, this has led to intentional misclassification or manipulation in order to pass off virgin materials as residues or to inflate volumes artificially.
Why does this happen?
- Market incentives: Wastes often qualify for double-counting under biofuel mandates or generate higher credits under emissions schemes, making them more profitable.
- Loopholes and opacity: In complex or informal supply chains, especially in regions with limited traceability infrastructure, it can be difficult to verify whether a material is genuinely waste.
- Regulatory grey areas: Definitions of ‘waste’ and ‘residue’ vary across jurisdictions, leaving room for interpretation or exploitation.
To counter these risks, RSB sets out clear requirements and expectations for operators and auditors. The following practices are explicitly prohibited:
- Deliberate production of residues (e.g. producing POME or PFAD not as a by-product but as a primary feedstock)
- Intentional contamination or downgrading of feedstocks to reclassify them as waste
- Duplication or falsification of Proofs of Sustainability (PoS) or supply chain documents
- Misreporting feedstock origin, classification, or GHG values
Violations of these requirements are treated as critical non-conformities by RSB, triggering immediate consequences such as suspension of certification.
By clearly defining and enforcing these boundaries, RSB reduces ambiguity, making it harder to game the system and easier to hold actors accountable.
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7. Auditing the point of origin: sampling and evidence
For traceability to hold up, certification systems must go beyond the trader and into the supply chain. RSB requires POs to conduct sampling and verification of points of origin, with independent, third-party on-site audits for first collectors of residues.
Sampling is risk-based and calculated according to a square root model, taking into account the total number of sites, risk profile, and material volume. If first collectors have not been previously audited, on-site visits are required; paper-based verification is allowed only in clearly defined, low-risk scenarios.
Auditors are also required to conduct plausibility checks during site visits. These could include:
- Checking the existence of the point of origin and the claimed size of the operation.
- Comparing declared volumes with observable production capacity and storage infrastructure.
- Reviewing historical production data and delivery records to identify inconsistencies.
- Interviewing site staff to confirm operating practices and feedstock sources.
- Cross-checking supplier claims against regional benchmarks or typical yield data, especially for residues with known variability.
These checks ensure that the quantities claimed in documentation are physically realistic and consistent with what can be reasonably produced or collected at the site. By verifying what’s on paper against what’s on the ground, RSB reduces the risk of overreporting, double-counting, or fraud, reinforcing confidence in the entire system.
This process ensures that what’s claimed on paper reflects reality on the ground, verified through systematic cross-checking of documentation and on-site observations during the audit.
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A note on the limits of certification – and our shared responsibility
No certification system, no matter how rigorous, can be entirely foolproof. Complex, global supply chains carry inherent risks, and while certification plays a critical role in identifying, managing, and mitigating those risks, it cannot eliminate them alone.
Certification is not a silver bullet. It’s one part of a broader ecosystem of accountability that must also include:
- Government and regulatory oversight that enforces fair rules and closes loopholes
- Buyers and brands who apply rigorous due diligence and prioritise substance over shortcuts
- Investors, NGOs, and independent voices who hold systems to account
- And certified operators and auditors who bring integrity to the everyday work of sustainability
When waste and residue feedstocks are increasingly valuable – and markets reward low-carbon intensity – it’s essential that the entire ecosystem works together to ensure that these materials are sourced and certified responsibly, not just expediently.
RSB is committed to taking a proactive role in strengthening the credibility of the wider certification ecosystem, both through our own system and through regulatory engagement. In 2025, RSB and its members jointly developed and submitted recommendations to the European Commission aimed at enhancing trust in RED III implementation. These recommendations include:
- Mandatory technical competence requirements for auditors.
- More consistent interpretation of waste and residue classifications across schemes.
- Improved transparency and oversight of CBs.
- Strengthened stakeholder consultation and public reporting requirements.
We are also reviewing our own assurance system through the RSB General Standards Working Group, focusing on the application of reasonable assurance, auditor training and oversight, and improved risk-based audit guidance. These efforts reflect our belief that credible certification systems are not static, and that they must evolve, with integrity, in response to real-world risks and expectations.
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Want to learn how RSB builds trust in waste and residue supply chains?
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