ISO 15270-5:2025

International
Standard
ISO 15270-5
First edition
Plastics — Guidelines for the recovery
2025-11
and recycling of plastics waste —
Part 5:
Organic/biological recycling
Plastiques — Lignes directrices pour la valorisation et le
recyclage des déchets plastiques —
Partie 5: Recyclage organique/biologique
Reference number
© ISO 2025
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Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Waste flows . 3
5 Separate collection of post-consumer waste . 4
5.1 Separate collection systems .4
5.2 Quality for organic recycling .4
6 Waste treatment plants undertaking organic/biological recycling. 5
7 Nature and quality of output (recyclate) . 8
8 How to determine the recycling rate of compostable plastics . 8
Annex A (informative) Composition analysis of bio-waste and discards .10
Bibliography .13

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
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this may not represent the latest information, which may be obtained from the patent database available at
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Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 14, Environmental
aspects.
This first edition of ISO 15270-5, together with ISO 15270-1, ISO 15270-2, ISO 15270-3 and ISO 15270-4,
cancels and replaces ISO 15270:2008, which has been technically revised.
The main changes are as follows:
— ISO 15270 has been turned into a series of five parts, where ISO 15270-1 is the succession of the essential
part of the second edition (2008) and specific methods and technological description of recycling
methods are given as ISO 15270-2, ISO 15270-3, ISO 15270-4 and ISO 15270-5.
A list of all parts in the ISO 15270 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
Kitchen waste, food scraps, lawn mowing and pruning branches are generally referred to as bio-waste,
since it is composed of biodegradable organic materials. Its intrinsic biodegradability makes it possible for
this waste to be recovered through biological processes, in which the breakdown and reorganization of the
waste into new substances takes place thanks to the action of microorganisms. In ecology, the term recycling
refers to the biogeochemical cycle, in particular to that of carbon. In the carbon cycle, organic compounds
formed from atmospheric CO through photosynthesis enter the food chain, are metabolised into different
compounds, transferred among different environmental compartments, and eventually oxidised back to
CO , closing the cycle.
The recycling of bio-waste takes place through processes that, regardless of size, lead to the production of
soil improvers under controlled conditions. These processes are aerobic composting or anaerobic digestion
preferably followed by aerobic composting of digestate.
NOTE The digestate is preferably aerobically composted after anaerobic digestion to maximise benefits to the
soil it is applied to afterwards and minimises some potential agro-environmental issues such as release of ammonia
and nitrates.
Currently, the predominant output of organic recycling is compost, a soil improver. The various components
of the organic waste are mixed in an appropriate way to favour a bio-reaction that transforms the initial
waste into a stable, odourless, and sanitized product i.e. compost, that is used in agriculture and horticulture.
However, in some countries the slurry-like digestate is applied to agricultural land before maturation. The
closure of the cycle (from bio-waste to soil improver back to the soil) is currently considered very important
to return the organic substances necessary to maintain fertility back to the soil.
If the waste treatment gives rise to a final output for which there is no advantageous use (for example because
the low quality makes it unsuitable for agriculture), then it cannot be defined as recycling. This concept is
taken up by some relevant legislations. For example, in Europe, a material produced by the treatment of bio-
waste whose quality is so low that it can only be used for backfilling operations cannot be considered the
[1]
result of recycling. The recycling of bio-waste is hindered by the presence of incompatible materials and
objects. Non-biodegradable objects (e.g. conventional plastics waste) represent a contamination for organic
recycling. Biodegradable plastics (e.g. that meet the criteria of ISO 17088), on the other hand, are potentially
suitable for organic recycling and can be used to make industrially compostable products and compostable
packaging made of compostable plastics. These products can be recovered together with the bio-waste
contributing to the formation of compost. Generally, the mixing between biodegradable plastic waste and
bio-waste is achieved, for example, when industrially compostable plastic waste is collected with bio-waste
(for example bags for separate collection of bio-waste, or tableware in collective catering) or tends to be
contaminated with bio-waste (some food packaging).
The term industrially compostable is widely used to indicate waste that has characteristics that make it
compatible with the separate collection and subsequent treatment of bio-waste. Therefore, in communication
with the consumers regarding the end of life of products, the term "industrially compostable" is not used
with a technical meaning, i.e. to refer to a specific waste treatment technology (i.e. aerobic treatment carried
out at high temperature) but as an indication on how to operate separate collection with it. In this document,
the term industrially compostable will be used in this spirit, i.e. as a synonym for "suitable to be collected
with bio-waste and recovered by means of organic recycling”.
Industrially compostable products and packaging made of compostable plastics (as defined in the relevant
standards, e.g. ISO 17088) contribute to the composting process and the production of compost similarly
to cellulose-based compounds, a main feedstock of composting. They are a source of carbon and energy.
Therefore, composting of biodegradable plastics is a form of recycling even if the result of this process is
very different from the original waste. The idea that recycling can give rise to products of a different nature
from that of the original waste is well established both at the standardization level (e.g. in the definition
of recycling from ISO 472) and at the legislative level. This concept is widely used in different legal and
[1]
national contexts. For example, the European Waste Framework Directive states that "recycling means
any recovery operation by which waste materials are reprocessed into products, materials or substances
whether for the original or other purposes. It includes the reprocessing of organic material but does not
include energy recovery and the reprocessing into materials that are to be used as fuels or for backfilling
operations". As another example, the legislation in force in the Russian Federation states that “waste

v
recycling from usage of goods means to use waste resulted from used goods or secondary raw materials,
[2]
processed from used goods, for manufacturing any products”.
Home composting is different from industrial composting. Home composting is a practice used by private
individuals to process at home garden and food waste generated at household level and produce compost
for personal gardening use. In spite of the common name, industrial and home composting are two very
different activities, the former being a controlled waste treatment process and the latter being a gardening
activity. Compost produced by a private individual is for his own use and not for provision to others, free of
charge or in return for payment. Thus, strictly speaking home composting cannot be classified as a recycling
activity for compostable plastic waste, as the concept of recycling implies the conservation of the economic
value still present in the waste and the production of materials/substances to be used in the economy either
for the original purpose or for other purposes. This is a concept that has been adopted in some relevant
[3]
legislation. For example, in the European Directive on Packaging and Packaging waste , it is stipulated
that only industrial composting processes that are realized under controlled conditions are relevant for
calculating organic recycling rates of compostable packaging waste, whereas home composting processes
are not taken into account.
Small-scale waste treatment systems can enable recycling if, regardless of size, they are based on controlled
processes that result in products (e.g. soil improvers).

vi
International Standard ISO 15270-5:2025(en)
Plastics — Guidelines for the recovery and recycling of
plastics waste —
Part 5:
Organic/biological recycling
1 Scope
This document establishes the terms, definitions, methodologies and calculations that are necessary for the
recovery and recycling of waste from plastic products and materials labelled as industrially compostable
through organic recycling. It identifies the different types of organic recycling technologies used in the
recovery and subsequent recycling
...