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Dual-use factors for refinery and petrochemical output products

Published 6 October 2026

Version 0.1
September 2026

Legislation	The Plastic Packaging Tax (Chemical Recycling Certification Schemes) Regulations 2027 – Regulation 5(3)
Target audience	Certified persons operating relevant refinery and petrochemical mass balance processes; certification bodies and auditors
Description	This document sets out how to assign dual-use factors to refinery and petrochemical output products, including the methodology for determining the dual-use factor of dual-use output products.
Contact details	teamindirecttaxdesign@hmrc.gov.uk

About this document

This document sets out the methodology referred to in regulation 5(3)(a) of the Plastic Packaging Tax (Chemical Recycling Certification Schemes) Regulations 2027 for determining the dual-use factor of refinery and petrochemical output products. Regulation 5 requires the dual-use factor to be determined in accordance with this methodology and supported by sufficient evidence. This document should be read alongside the Regulations and the notice published by the Commissioners under regulation 5(4) specifying what constitutes sufficient evidence.

1. Overview

The fuel-excluded attribution method prevents recycled material associated with output products that are fuel, or are used to produce fuel, from being attributed to other outputs from the same process. Regulation 5 of the Plastic Packaging Tax (Chemical Recycling Certification Schemes) Regulations 2027 require output products to be assigned a dual-use factor (DUF) to determine how much of the material is classified as fuel or for use in the production of fuel. Section 3 of this document contains the methodology referred to in that regulation.

The DUF represents the proportion of the output product that remains on a technically feasible recycling pathway. The DUF will range from 0 to 1 depending on that proportion. A technically feasible recycling pathway is a route by which plastic waste is reprocessed through one or more processes that changes the chemical structure of the plastic waste and produces outputs that are used in the manufacture of new products, rather than for use as fuel or in the production of fuel.

2. Output product classifications

The classification of some output products may be straightforward, as it may already be established that they are intended entirely for use as fuel or for use in the manufacture of new products other than fuel. For other products, the classification is more complex because they can have multiple uses. Output products are classified as fuel-use, non-fuel or dual-use products. The table below sets out the definition of each category and its DUF.

Classification	Definition	DUF
Fuel-use products	An output product that is: Fuel; Used in the production of fuel; Consumed to provide energy for the process	0
Non-fuel products	An output product that is a chemical, polymer, or other non-fuel product, or used in the production of such products	1
Dual-use products	An output product that can be used in the production of fuel-use products or non-fuel products	Between 0 and 1 depending on the proportion that remains on a technically feasible recycling pathway (see section 3 of this document)

3. Methodology for determining the DUFs to dual-use output products

To determine the DUF for a dual-use output product, you must establish the proportion of the output product that can be steam cracked, that is, the proportion that is below the maximum acceptable boiling point (MABP) of the steam cracker or crackers. To do this, you must:

1. Establish the MABP of the steam cracker or crackers of the site that the output product will be further processed.
2. Using the MABP of the relevant steam cracker or crackers and the boiling range distribution of the dual-use output product, determine the proportion of the dual-use output product that can be steam cracked.
3. Assign a DUF from a range of 0 to 1 that is equal to the proportion of the dual-use output product determined at step 2.

For heavy or solid outputs, such as heavy gas oils, you must:

1. Establish and evidence the proportion of the heavy or solid dual-use output product that remains on a technically feasible recycling pathway.
2. Assign a DUF from a range of 0 to 1 that is equal to the proportion of the heavy or solid dual-use output product determined at step 1.

Sufficient evidence of assigned DUFs must be kept and provided to the auditor from your chosen accredited certification body. What is considered sufficient evidence is set out in notice under Regulation 5(4) of the Plastic Packaging Tax (Chemical Recycling Certification Schemes) Regulations 2027.

Default DUFs based on industry data may be assigned to output products. These default DUFs are listed in Annex A of this document.

Annex A: Default Dual-use Factors

Output product	Default DUF
[Data needed]	[Data needed]
[Data needed]	[Data needed]
[Data needed]	[Data needed]
[Data needed]	[Data needed]
[Data needed]	[Data needed]