SIST EN ISO 10993-7:2026

Biological evaluation of medical devices - Part 7: Ethylene oxide sterilization residuals (ISO 10993-7:2026)

This document specifies allowable limits (AL) for residual ethylene oxide (EO) and ethylene chlorohydrin (ECH) in EO-sterilized medical devices, procedures for the measurement of EO and ECH, and methods for determining conformity so that devices can be released. Additional background, including guidance and a flowchart showing how this document is applied, are also included in Annexes A, B, C, D, E, F, G, H, I, J and K.
EO-sterilized devices or components that have neither direct nor indirect body or user contact (e.g. in vitro diagnostic devices) are out of scope of this document. This document does not apply to devices that have been demonstrated to not absorb or retain EO or its degradation product ECH, such as medical devices made exclusively of metal alloys and glass, see Clause C.5[228].
NOTE            This document does not specify limits for ethylene glycol (EG). No device limits are specified for EG because the risk assessment in Annex F indicates that calculated allowable levels are higher than those likely to occur in a medical device.

Biologische Beurteilung von Medizinprodukten - Teil 7: Ethylenoxid-Sterilisationsrückstände (ISO 10993-7:2026)

Dieses Dokument legt die zulässigen Grenzwerte (ALs, en: allowable limits) für den Restgehalt von Ethylenoxid (EO) und Ethylenchlorhydrin (ECH) in mit EO sterilisierten Medizinprodukten, die Verfahren für die Messung von EO und ECH sowie die Verfahren für die Bestimmung der Übereinstimmung fest, damit die Produkte freigegeben werden können. Weitere Hintergrundinformationen, eine Anleitung und ein Flussdiagramm, auf dem dargestellt ist, wie dieses Dokument angewendet wird, sind ebenfalls in Anhang A, Anhang B, Anhang C, Anhang D, Anhang E, Anhang F, Anhang G, Anhang H, Anhang I, Anhang J und Anhang K enthalten.
EO-sterilisierte Produkte oder Komponenten, die weder direkten noch indirekten Körper- oder Anwenderkontakt haben (z. B. In-vitro-Diagnostika), liegen außerhalb des Anwendungsbereiches dieses Dokuments. Dieses Dokument gilt nicht für Produkte, für die nachgewiesen wurde, dass sie EO oder dessen Abbauprodukt ECH nicht absorbieren oder zurückhalten, beispielsweise Medizinprodukte, die ausschließlich aus Metalllegierungen und Glas hergestellt wurden, siehe Abschnitt C.5 [228].
ANMERKUNG   Dieses Dokument spezifiziert keine Grenzwerte für Ethylenglykol (EG). Für EG wurden keine produktbezogenen Grenzwerte festgelegt, da die Risikoabschätzung in Anhang F ergeben hat, dass die berechneten zulässigen Gehalte höher sind als die voraussichtlich bei einem Medizinprodukt auftretenden Gehalte.

Évaluation biologique des dispositifs médicaux - Partie 7: Résidus de stérilisation à l'oxyde d'éthylène (ISO 10993-7:2026)

Le présent document spécifie les limites admissibles (AL) des résidus d'oxyde d'éthylène (OE) et de chlorhydrate d'éthylène (ECH) pour des dispositifs médicaux stérilisés à l'oxyde d'éthylène, les modes opératoires pour le mesurage de l'oxyde d'éthylène et du chlorhydrate d'éthylène et les méthodes de mesure en vue de déterminer leur conformité et de procéder à leur libération. Des informations supplémentaires, comprenant des recommandations et un organigramme montrant comment le présent document est appliqué, sont également incluses dans les Annexe A, Annexe B, Annexe C, Annexe D, Annexe E, Annexe F, Annexe G, Annexe H, Annexe I, Annexe J et Annexe K.
Les dispositifs stérilisés à l'oxyde d'éthylène ne présentant pas de contact direct ou indirect avec le patient ou avec l'utilisateur (par exemple, les dispositifs de diagnostic in vitro) ne sont pas couverts par le présent document. Le présent document ne s'applique pas aux dispositifs dont il a été démontré qu'ils n'absorbent ni ne retiennent l'oxyde d'éthylène ou son produit de dégradation, le chlorhydrate d'éthylène, tels que les dispositifs médicaux constitués exclusivement d'alliages métalliques et de verre, voir l'Article C.5[228].
NOTE            Le présent document ne spécifie pas les limites pour l'éthylène glycol (EG). Aucune limite d'exposition n'est définie pour l'éthylène glycol (EG), car l'estimation du risque dans l'Annexe F indique que les niveaux admissibles calculés sont supérieurs à ceux susceptibles d'être trouvés dans un dispositif médical.

Biološka ocena medicinskih pripomočkov - 7. del: Ostanki sterilizacije z etilen oksidom (ISO 10993-7:2026)

Ta dokument določa dopustne meje (AL) za preostali etilen oksid (EO) in etilen klorohidrin (ECH) v medicinskih pripomočkih steriliziranih z EO, postopke za merjenje EO in ECH ter metode za ugotavljanje skladnosti, da se lahko pripomočki sprostijo. Dodatno ozadje, vključno s smernicami in diagramom poteka, ki prikazuje, kako se ta dokument uporablja, je vključeno tudi v prilogah A, B, C, D, E, F, G, H, I, J in K.
Pripomočki ali komponente sterilizirane z EO, ki nimajo niti neposrednega niti posrednega stika s telesom ali uporabnikom (npr. in vitro diagnostični pripomočki), niso zajeti v področje uporabe tega dokumenta. Ta dokument se ne uporablja za pripomočke, za katere je bilo dokazano, da ne absorbirajo ali zadržujejo EO ali njegovega razgradnega produkta ECH, kot so medicinski pripomočki, izdelani izključno iz kovinskih zlitin in stekla, glej točko C.5[228].
OPOMBA Ta dokument ne določa mej za etilen glikol (EG). Za EG niso določene meje za pripomočke, ker ocena tveganja v prilogi F kaže, da so izračunane dopustne ravni višje od tistih, ki bi se verjetno pojavile v medicinskem pripomočku.

General Information

• Status: Published
• Public Enquiry End Date: 08-Sep-2024
• Publication Date: 10-Jun-2026
• ICS: 11.100.20 - Biological evaluation of medical devices
• Technical Committee: VAZ - Healthcare
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 28-May-2026
• Due Date: 02-Aug-2026
• Completion Date: 11-Jun-2026
• Directive: Harmonized Standard2017/745 - Regulation (EU) 2017/745 of the European Parliament and of the Council of 5 April 2017 on medical devices, amending Directive 2001/83/EC, Regulation (EC) No 178/2002 and Regulation (EC) No 1223/2009 and repealing Council Directives 90/385/EEC and 93/42/EEC
• Mandate: M/575 - Medical devices in support of Regulation (EU) 2017/745 and in vitro diagnostic medical devices in support of Regulation (EU) 2017/746
• Mandate: M/575 Amd 2 - Medical devices in support of Regulation (EU) 2017/745 and in vitro diagnostic medicial devices in support of Regulation (EU) 2017746
• Ref Project: EN ISO 10993-7:2026 - Biological evaluation of medical devices - Part 7: Ethylene oxide sterilization residuals (ISO 10993-7:2026)

Relations

• Replaces: SIST EN ISO 10993-7:2009/A1:2022 - Biological evaluation of medical devices - Part 7: Ethylene oxide sterilization residuals - Amendment 1: Applicability of allowable limits for neonates and infants (ISO 10993-7:2008/Amd 1:2019)
• Effective Date: 01-Jul-2026
• Replaces: SIST EN ISO 10993-7:2009/AC:2010 - Biological evaluation of medical devices - Part 7: Ethylene oxide sterilization residuals - Technical Corrigendum 1 (ISO 10993-7:2008/Cor 1:2009)
• Effective Date: 01-Jul-2026
• Replaces: SIST EN ISO 10993-7:2009 - Biological evaluation of medical devices - Part 7: Ethylene oxide sterilization residuals (ISO 10993-7:2008)
• Effective Date: 01-Jul-2026
• Referred By: SIST EN 455-3:2007 - Medical gloves for single use - Part 3: Requirements and testing for biological evaluation
• Effective Date: 27-May-2026
• Referred By: SIST EN 12022:2000 - Blood gas exchangers
• Effective Date: 27-May-2026
• Referred By: SIST-TS CEN/TS 15277:2006 - Non-active surgical implants - Injectable implants
• Effective Date: 27-May-2026
• Referred By: SIST EN 60601-1:2007/A2:2021 - Medical electrical equipment - Part 1: General requirements for basic safety and essential performance (IEC 60601-1:2005/A2:2020)
• Effective Date: 27-May-2026

Overview

SIST EN ISO 10993-7:2026 outlines requirements for the biological evaluation of medical devices, specifically addressing the management of residual ethylene oxide (EO) and ethylene chlorohydrin (ECH) in sterilized products. Issued by the Slovenian Institute for Standardization (SIST), this standard serves as a key reference for manufacturers, regulatory bodies, and testing laboratories when ensuring the safety of EO-sterilized medical devices. It includes methods for measuring EO and ECH residuals, defines allowable limits, and describes processes for determining compliance before device release. The guidance supports the risk management of chemical residuals to limit patient and user exposure, aligning with internationally recognized best practices and regulatory requirements.

Key Topics

• Allowable Limits (AL): Specifies maximum levels for EO and ECH residuals on medical devices, based on exposure duration and patient population.
• Device Categorization: Defines exposure categories-limited (<24 hours), prolonged (24 hours to 30 days), and long-term (>30 days) contact-to set appropriate residual limits.
• Measurement Procedures: Details validated sampling, extraction, and analytical methods for detecting and quantifying EO and ECH.
• Compliance Determination: Outlines conformity assessment methods and release procedures, including batch release and use of residual dissipation curves.
• Risk-Based Approach: Allows alternative limits through documented toxicological risk assessment by considering device usage scenarios and intended patient groups.
• Annex Guidance: Provides supporting information, examples, and flowcharts for practical implementation of the standard.

Applications

SIST EN ISO 10993-7:2026 is intended for use in the design, manufacturing, and regulatory approval of EO-sterilized medical devices that contact patients or users. Applications include:

• Medical Device Manufacturing: Ensures new and existing products meet safety requirements per EO/ECH residual limits before market release.
• Sterilization Process Validation: Guides sterilization cycle development and routine control, helping manufacturers optimize parameters such as EO concentration, dwell time, and aeration.
• Risk Assessment: Supports preparation of documentation for regulatory submissions by justifying residual levels through risk assessments that reflect product design and intended use.
• Product Release Decisions: Assists in batch release and routine monitoring, verifying that device residuals are within acceptable limits at the point of distribution.
• Process Optimization: Enables manufacturers to select and qualify safer materials or alternative sterilization methods, reducing residual chemical exposure risk to patients.

Devices with no direct or indirect body or user contact, such as certain in vitro diagnostic devices, and those made solely from materials not retaining EO or ECH (e.g., glass or metal), are out of scope.

Related Standards

For comprehensive compliance and process integration, consider the following related international standards:

• ISO 10993-1: Biological evaluation of medical devices – Part 1: Evaluation and testing within a risk management process
• ISO 11135: Sterilization of health care products – Ethylene oxide – Requirements for the development, validation, and routine control of a sterilization process
• ISO 10993-17: Biological evaluation of medical devices – Part 17: Toxicological risk assessment of medical device constituents
• ISO 10993-23: Biological evaluation of medical devices – Part 23: Tests for irritation

By adhering to SIST EN ISO 10993-7:2026, manufacturers can demonstrate effective control of EO and ECH residuals, enhance patient safety, and ensure regulatory compliance in accordance with international biological evaluation standards for medical devices.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2026
Nadomešča:
SIST EN ISO 10993-7:2009
SIST EN ISO 10993-7:2009/A1:2022
SIST EN ISO 10993-7:2009/AC:2010
Biološko ovrednotenje medicinskih pripomočkov - 7. del: Ostanki po sterilizaciji z
etilenoksidom (ISO 10993-7:2026)
Biological evaluation of medical devices - Part 7: Ethylene oxide sterilization residuals
(ISO 10993-7:2026)
Biologische Beurteilung von Medizinprodukten - Teil 7: Ethylenoxid-
Sterilisationsrückstände (ISO 10993-7:2026)
Évaluation biologique des dispositifs médicaux - Partie 7: Résidus de stérilisation à
l'oxyde d'éthylène (ISO 10993-7:2026)
Ta slovenski standard je istoveten z: EN ISO 10993-7:2026
ICS:
11.100.20 Biološko ovrednotenje Biological evaluation of
medicinskih pripomočkov medical devices
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 10993-7
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2026
EUROPÄISCHE NORM
ICS 11.100.20 Supersedes EN ISO 10993-7:2008, EN ISO 10993-
7:2008/AC:2009, EN ISO 10993-7:2008/A1:2022
English Version
Biological evaluation of medical devices - Part 7: Ethylene
oxide sterilization residuals (ISO 10993-7:2026)
Évaluation biologique des dispositifs médicaux - Partie Biologische Beurteilung von Medizinprodukten - Teil 7:
7: Résidus de stérilisation à l'oxyde d'éthylène (ISO Ethylenoxid-Sterilisationsrückstände (ISO 10993-
10993-7:2026) 7:2026)
This European Standard was approved by CEN on 17 February 2026.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 10993-7:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Annex ZA (informative) Relationship between this European Standard the General Safety
and Performance Requirements of Regulation (EU) 2017/745 aimed to be covered . 4

European foreword
This document (EN ISO 10993-7:2026) has been prepared by Technical Committee ISO/TC 194
"Biological and clinical evaluation of medical devices" in collaboration with Technical Committee
CEN/TC 206 “Biological and clinical evaluation of medical devices” the secretariat of which is held by
DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by November 2026, and conflicting national standards
shall be withdrawn at the latest by November 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 10993-7:2008, EN ISO 10993- 7:2008/AC:2009, EN ISO 10993-
7:2008/A1:2022.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
For the relationship with EU Legislation, see informative Annex ZA, which is an integral part of this
document.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 10993-7:2026 has been approved by CEN as EN ISO 10993-7:2026 without any
modification.
Annex ZA
(informative)
Relationship between this European Standard the General Safety and
Performance Requirements of Regulation (EU) 2017/745 aimed to be
covered
This European standard has been prepared under M/575 to provide one voluntary means of
conforming to the General Safety and Performance Requirements of Regulation (EU) 2017/745 of 5
April 2017 concerning medical devices [OJ L 117] and to system or process requirements including
those relating to quality management systems, risk management, post-market surveillance systems,
clinical investigations, clinical evaluation or post-market clinical follow-up.
Once this standard is cited in the Official Journal of the European Union under that Regulation,
compliance with the normative clauses of this standard given in Table ZA.1 and application of the
edition of the normatively referenced standards as given in Table ZA.2 confers, within the limits of the
scope of this standard, a presumption of conformity with the corresponding General Safety and
Performance Requirements of that Regulation, and associated EFTA Regulations.
Where a definition in this harmonised standard differs from a definition of the same term set out in
Regulation (EU) 2017/745, the differences shall be indicated in the Annex Z. For the purpose of using
this standard in support of the requirements set out in Regulation (EU) 2017/745, the definitions set
out in this Regulation prevail.
Where the European standard is an adoption of an International Standard, the scope of this document
can differ from the scope of the European Regulation that it supports. As the scope of the applicable
regulatory requirements differ from nation to nation and region to region the standard can only
support European regulatory requirements to the extent of the scope of the European Regulation for
medical devices ((EU) 2017/745).
NOTE 1 Where a reference from a clause of this standard to the risk management process is made, the risk
management process needs to be in compliance with Regulation (EU) 2017/745. This means that risks have to be
‘reduced as far as possible’, ‘reduced to the lowest possible level’, ‘reduced as far as possible and appropriate’,
‘removed or reduced as far as possible’, ‘eliminated or reduced as far as possible’, ’removed or minimized as far as
possible’, or ‘minimized’, according to the wording of the corresponding General Safety and Performance
Requirement.
NOTE 2 The manufacturer’s policy for determining acceptable risk must be in compliance with General Safety
and Performance Requirements 1, 2, 3, 4, 5, 8, 9, 10, 11, 14, 16, 17, 18, 19, 20, 21 and 22 of the Regulation.
NOTE 3 When a General Safety and Performance Requirement does not appear in Table ZA.1, it means that it is
not addressed by this European Standard.
Table ZA.1 — Correspondence between this European Standard and Annex I of
Regulation (EU) 2017/745 [OJ L 117] and to system or process requirements including those relating
to quality management systems, risk management, post-market surveillance systems, clinical
investigations, clinical evaluation or post-market clinical follow-up
General Safety and
Clause(s) / sub-
Performance
clause(s)
Requirements of Remarks / Notes
Regulation (EU)
of this EN
2017/745
This document addresses the Ethylene oxide (EO)
sterilization method rather than choice of materials
for a medical device or the method’s impact on the
properties of a material. Flammability and
mechanical or physical (e.g., surface) properties are
not covered. This document provides requirements
for a toxicological risk assessment process for EO
sterilization residues present in or on, or released
from, a medical device.
EO sterilization residues have the capacity to
interact with biological tissues, cells or body fluids
and the document provides a process for assessing
the likelihood of any associated harm to health
arising as a result of exposure to EO sterilization
residues during the intended use of the medical
device. Such an assessment can confirm the absence
of appreciable toxicological risk and verify that
exposure to EO sterilization residues from the device
should not result in an adverse reaction in biological
10.1 (a), (b), (d), (e), and
4, 5
tissues, cells or body fluids.
(h)
The document only addresses toxicological risks
associated with the use of EO as a processing
material; the toxicological risk assessment of all
other processing materials used and the impact of
processes on the properties of the materials of
manufacture is not covered by this document.
The document provides requirements for a process
for measuring the level of potential exposure to EO
sterilization residues in or on a medical device (4.4)
and for confirming that the exposure estimate meets
specifications (allowable limits, 4.3) determined to
be without appreciable harm to health, defined with
respect to residues of EO and its reaction product
ECH only. The allowable limits are chemical
specifications based on kinetic modelling. The
document specifies requirements for the release of
medical devices for use following verification that
allowable limits are met (Clause 5).
General Safety and
Clause(s) / sub-
Performance
clause(s)
Requirements of Remarks / Notes
Regulation (EU)
of this EN
2017/745
The document addresses risks posed by EO
sterilization residues.
This document provides methods for manufacturers
to control the risks posed by exposure to EO
sterilization residues to the patient during normal
product use, taking into account the intended use as
well as duration and frequency of exposure. Since EO
sterilization residues are a subset of residues which
are associated with medical devices, the GSPR is only
covered by this document with respect to EO
sterilization residues.
10.2 4, 5
The document specifies maximum allowable doses of
EO sterilization residuals delivered to patients
regarding different patient populations but does not
provide maximum allowable doses of EO
sterilization residuals to persons involved in the
transport, storage or use of the device.
Maximum allowable doses for special situations
regarding different contacting tissues are addressed.
Devices or components that have neither direct nor
indirect patient contact are not addressed.
The document addresses risks posed by processing
residues associated with the EO sterilization process.
This document provides a method for manufacturers
to estimate the release of EO sterilization residues
from the medical devices and provides means to
demonstrate that they have been reduced to a level
that will be without appreciable harm to health.
10.4.1 1st paragraph 4, 5
However, the GSPR is only partly covered by this
document, since EO sterilization residues are only a
subset of the processing residues associated with the
manufacture of a medical device. This document also
does not provide requirements for design and
manufacture, nor does it address risks associated
with particles, including wear debris and
degradation products from medical devices.
The document is applicable for all medical devices in
direct or indirect contact to the patient and includes
the listed contact categories.
10.4.1 2nd paragraph 4, 5
This document does not provide a method to
determine whether EO is present in concentrations
above 0,1% weight by weight (w/w) in devices,
those parts thereof or those materials used therein.
10.4.1 (a) 4, 5
The document addresses ethylene oxide which is
General Safety and
Clause(s) / sub-
Performance
clause(s)
Requirements of Remarks / Notes
Regulation (EU)
of this EN
2017/745
listed in Part 3 of Annex VI of Regulation (EC) No
1272/2008. EO may cause genetic defects (Muta.
1B), may cause cancer (Carc. 1B), may damage
fertility and is suspected of damaging the unborn
child (Repr. 1B).
The document provides methods for the analysis and
estimation of potential patient or user exposure to
EO. The document specifies maximum allowable
10.4.2 (a), (c) 4, 5 doses of EO residuals delivered to patients regarding
different patient populations that can form a basis
for a justification regarding the presence of the
substance.
Table ZA.2 — Normative references from Clause 2 of this document and their corresponding
European publications
Column 1 Reference Column 2 Column 3 Column 4
in Clause 2 International
Title Corresponding
Standard Edition
European Standard
Edition
ISO 10993-1:2025 ISO 10993-1:2025 Biological evaluation of EN ISO 10993-1:2025
medical devices — Part 1:
Requirements and general
principles for the evaluation
of biological safety within a
risk management process
ISO 10993-23:2021 ISO 10993-23:2021 Biological evaluation of EN ISO 10993-23:2021
medical devices — Part 23:
Tests for irritation
The documents listed in the Column 1 of Table ZA.2, in whole or in part, are normatively referenced in
this document, i.e. are indispensable for its application. The achievement of the presumption of
conformity is subject to the application of the edition of Standards as listed in Column 4 or, if no
European Standard Edition exists, the International Standard Edition given in Column 2 of Table ZA.2.
Table ZA.3 — Prevailing terms of Regulation (EU) 2017/754 for the use of this European
standard under that Regulation
Article in (EU)
Clause(s)/sub-
Differences/
Term used in 2017/745 that
Clause(s)
this EN defines or uses
Consequences
of this EN
this term
Implant 3.11 Article 2 (5) The definition is substantially equivalent. The
difference between “implant” and “implantable
device” in the MDR is only a clarification and
this is already implicit in the definition
provided in 3.11.
WARNING 1 — Presumption of conformity stays valid only as long as a reference to this European
standard is maintained in the list published in the Official Journal of the European Union. Users of this
standard should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2 — Other Union legislation may be applicable to the product(s) falling within the scope of
this standard.
International
Standard
ISO 10993-7
Third edition
Biological evaluation of medical
2026-04
devices —
Part 7:
Ethylene oxide sterilization
residuals
Évaluation biologique des dispositifs médicaux —
Partie 7: Résidus de stérilisation à l'oxyde d'éthylène
Reference number
ISO 10993-7:2026(en) © ISO 2026

ISO 10993-7:2026(en)
© ISO 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
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Published in Switzerland
ii
ISO 10993-7:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 5
4.1 General .5
4.2 Categorization of devices .6
4.3 Allowable limits .6
4.3.1 General .6
4.3.2 Limited exposure devices .8
4.3.3 Prolonged exposure devices .9
4.3.4 Long-term exposure devices .9
4.3.5 Special situations .11
4.3.6 Tolerable contact level . 12
4.4 Determination of EO and ECH residuals . 12
4.4.1 Procedure . 12
4.4.2 Test method validation . 12
4.4.3 Product sampling . 12
4.4.4 Sample/fluid ratios . . 13
4.4.5 Product extraction . 13
4.4.6 Multi-device systems . 13
5 Product release .13
5.1 General . 13
5.2 Batch release of products . .14
5.3 Release of products at specified minimum aeration time .14
5.4 Procedure for product release using residual dissipation curves .14
6 Adoption of products into established aeration family .15
7 Change evaluation .15
Annex A (informative) Guidance for the application of this document for the determination of
EO and ECH residuals in medical devices .16
Annex B (informative) Factors influencing product residuals .27
Annex C (informative) Rationale for the provisions of this document .30
Annex D (informative) Establishment of allowable limits for EO .38
Annex E (informative) Establishment of allowable limits for ECH .56
Annex F (informative) Ethylene glycol.66
Annex G (normative) Evaluation of gas chromatograms .70
Annex H (informative) Gas chromatographic determination for EO and ECH . 74
Annex I (informative) Preparation of EO and ECH standards .78
Annex J (informative) Ethylene oxide and ethylene chlorohydrin residual measuring methods .82
Annex K (informative) Examples of product release methods .90
Bibliography .109

iii
ISO 10993-7:2026(en)
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)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 194, Biological and clinical evaluation of medical
devices, in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/
TC 206, Biological and clinical evaluation of medical devices, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 10993-7:2008), which has been technically
revised. It also incorporates the Amendment ISO 10993-7:2008/Amd 1:2019 and the Technical Corrigendum
ISO 10993-7:2008/Cor 1:2009.
The main changes are as follows:
— allowable limits and extraction conditions have been derived based on the patient population and the
duration of use;
— the use of a risk assessment to establish allowable limits has been permitted;
— additional guidance on product release has been provided;
— additional guidance on determining residuals and the factors that affect residual has been provided.
A list of all parts in the ISO 10993 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
ISO 10993-7:2026(en)
Introduction
As noted in the introduction to ISO 11135, when determining the suitability of ethylene oxide (EO) for
sterilization of medical devices, it is important to ensure that the levels of residual EO and ethylene
chlorohydrin (ECH) pose a minimal risk to the patient in intended product use. Therefore, it is important
that the use of alternative materials and sterilization processes are considered during product design
and development. EO is known to exhibit a number of biological effects. In the development of this
document, consideration was given to these effects, which include irritation, organ damage, mutagenicity,
carcinogenicity, and reproductive effects in humans and animals. Similar consideration was given to the
harmful effects of ECH and ethylene glycol (EG). ECH can be formed when EO comes into contact with free
chloride ions, whereas EG is a hydrolytic reaction product of EO and water. In practice, for most devices,
exposure to EO and ECH is considerably lower than the maximum allowable limits established according to
this document. No allowable limits are set for EG because risk assessment indicated that when EO residuals
are controlled, it is unlikely that biologically significant residuals of EG would be present.
Requirements herein are in addition to the biological evaluation requirements as indicated in ISO 10993-1.
The biological evaluation, combined with the EO-sterilization process residual limits, form the justification
that an EO-sterilized device is safe for its anticipated contact duration. Maximum allowable residuals for
ECH, when ECH has been found to be present in medical devices sterilized with EO, are also specified. Local
effects (e.g. irritation) have been considered and are incorporated in the TCL as given in 4.3.6.2 and Annex D
for EO, and in 4.3.6.3 and Annex E for ECH.
In this edition of this document (i.e. ISO 10993-7:2026), an uncertainty factor approach is used to derive EO
and ECH exposure duration-specific tolerable intake (TI) values (expressed in µg/kg/d). Furthermore, this
edition of this document (i.e. ISO 10993-7:2026) introduces the conversion of each EO and ECH TI value into
subpopulation-specific cumulative exposure-allowable limit values (expressed in milligrams per device),
which are used to determine the extent that EO and ECH, extracted under clinically relevant conditions and
time-periods, needs to be reduced post-sterilization.
This edition of this document (i.e. ISO 10993-7:2026) applies a different approach as compared to
ISO 10993-17:2023 to establishing allowable limits to make it useful for development, validation, and
routine control of ethylene oxide sterilization in the manufacture of finished medical devices with focus
on the risk assessments associated with three chemical constituents that are potentially left in medical
devices sterilized with ethylene oxide. This document extends this knowledge further by calculating the
largest amount of EO, ECH or EG that can be present in a medical device such that it would always meet
the requirements of ISO 10993-17 when that device has been exposed to the validated sterilization cycle
parameters. This maximum amount or allowable limit is expressed in milligrams per device deemed
acceptable when taken into the body through exposure to that medical device. These allowable limits will
help determine the appropriate sterilization parameters such as sterilant gas concentration and dwell, as
well as aeration temperature and hold time when validating the sterilization process to be used for a product
or group of products. Furthermore, the allowable limits can be used by regulatory bodies, manufacturers,
and processors to optimize processes and aid in the selection and qualification of alternative materials in
order to protect patient health.

v
International Standard ISO 10993-7:2026(en)
Biological evaluation of medical devices —
Part 7:
Ethylene oxide sterilization residuals
1 Scope
This document specifies allowable limits (AL) for residual ethylene oxide (EO) and ethylene chlorohydrin
(ECH) in EO-sterilized medical devices, procedures for the measurement of EO and ECH, and methods for
determining conformity so that devices can be released. Additional background, including guidance and a
flowchart showing how this document is applied, are also included in Annexes A, B, C, D, E, F, G, H, I, J and K.
EO-sterilized devices or components that have neither direct nor indirect body or user contact (e.g. in vitro
diagnostic devices) are out of scope of this document. This document does not apply to devices that have
been demonstrated to not absorb or retain EO or its degradation product ECH, such as medical devices made
[228]
exclusively of metal alloys and glass, see Clause C.5 .
NOTE This document does not specify limits for ethylene glycol (EG). No device limits are specified for EG because
the risk assessment in Annex F indicates that calculated allowable levels are higher than those likely to occur in a
medical device.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 10993-1:2025, Biological evaluation of medical devices — Part 1: Evaluation and testing within a risk
management process
ISO 10993-23:2021, Biological evaluation of medical devices — Part 23: Tests for irritation
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10993-1 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
aeration
part of the sterilization cycle (3.5) during which the sterilizing agent and/or its reaction products desorb
from the health care product until predetermined levels are reached
Note 1 to entry: Aeration can be performed within the sterilization chamber or in a separate chamber or room.
[SOURCE: ISO 11139:2018, 3.7, modified — Note 1 to entry has been added.]

ISO 10993-7:2026(en)
3.2
allowable limit
AL
amount of residual (3.19) ethylene oxide or ethylene chlorohydrin on a single device that is permitted as a
condition of release for patient use
Note 1 to entry: Allowable limits are expressed in milligrams per device for each applicable exposure period. These
limits represent acceptable biological risks for medical devices under the circumstances of their anticipated exposure
duration.
3.3
cumulative exposure
total quantity of ethylene oxide and ethylene chlorohydrin that contacts the body for a specified period of
time
Note 1 to entry: Cumulative exposure can apply when consecutive uses of the same device or of new devices of the
same type for the same patient or user applies (e.g. when one device is used repeatedly over a specified period of time).
3.4
concomitant exposure factor
CEF
numerical safety (3.20) factor that accounts for patient exposure to the simultaneous use of other ethylene
oxide sterilized medical devices different from the subject medical device
Note 1 to entry: CEF is calculated from the reciprocal of the number of devices (one divided by the number of devices)
used during a procedure. The default value (3.6) of 0,2 assumes four other devices are used during a procedure, see
4.4.5 and Clause D.6 for further details.
3.5
cycle
set of sterilization process parameters
3.6
default value
value or factor used in the derivation of a tolerable contact level (3.22) or tolerable intake (3.24), in the
absence of specific data [e.g. an uncertainty factor (3.26)]
[SOURCE: ISO 10993-17:2023, 3.5, modified — the "worst-case exposure dose" has been removed from the
definition.]
3.7
dose-response
relationship of dosage to observable harm
Note 1 to entry: In general, there are two types of dose-response relationships. The first type is the change in response
of an individual to a range of doses. The second type is the distribution of the response among individuals to a range
of doses.
[SOURCE: ISO 10993-17:2023, 3.6]
3.8
exhaustive extraction
multi-step extraction conducted until the amount of material extracted in a subsequent extraction step is
less than 10 % of that determined in the initial extraction step
Note 1 to entry: Based upon the boiling point of ethylene oxide (EO) (10,7 °C) and the knowledge that substances,
other than EO and ethylene chlorohydrin, can be extracted from the device under evaluation, gravimetric analysis is
not appropriate for determining the exhaustivity level.
[SOURCE: ISO 10993-18:2020, 3.15, modified — "by gravimetric analysis (or achieved by other means)" has
been removed from the definition and Note 1 to entry has been added.]

ISO 10993-7:2026(en)
3.9
harm to health
adverse reaction, such as altered morphology, physiology, growth, development, reproduction or lifespan
that
a) impairs function of an organ or system, organism or (sub)population,
b) reduces capacity to tolerate an impaired function, or
c) increases susceptibility to other influences that impair function
Note 1 to entry: Examples of (sub)population include, but are not limited to: male, female, preterm neonates, adults.
[SOURCE: ISO 10993-17:2023, 3.8]
3.10
load
sterilization batch
sterilization load
product, equipment or materials to be processed together within an operating cycle (3.5)
[SOURCE: ISO 11139:2018, 3.155, modified — the admitted terms "sterilization batch" and "sterilization
load" have been added.]
3.11
implant
medical device, or component thereof, that is intended to be introduced into the human body or to replace an
epithelial surface or the surface of the eye, by means of surgical intervention and that is intended to remain
in place after the procedure
Note 1 to entry: The duration of an implant remaining in the body is dependent on the clinical need.
[SOURCE: ISO 10993-1:2025, 3.21]
3.12
irritation
localized non-specific inflammatory response to single, repeated or continuous application of a substance/
material
Note 1 to entry: Skin irritation is a reversible reaction and is mainly characterized by local erythema (redness) and
swelling (oedema) of the skin.
[SOURCE: ISO 10993-23:2021, 3.7]
3.13
lowest observed adverse effect level
LOAEL
lowest concentration or amount of an identified constituent found by experiment or observation which
causes detectable harm to health (3.9) to the target organism under defined conditions of exposure
[SOURCE: ISO 10993-17:2023, 3.13, modified — Note 1 to entry has been deleted.]
3.14
minimally irritating level
MIL
lowest amount per surface area of an identified constituent that is irritating to the tissue at the contact site
as determined by valid experimental or observational evidence
Note 1 to entry: The minimally irritating level is expressed in microgram per centimetre squared (μg/cm ).
[SOURCE: ISO 10993-17:2023, 3.15]

ISO 10993-7:2026(en)
3.15
modifying factor
MF
mathematical product of uncertainty factors (3.26)
[SOURCE: ISO 10993-17:2023, 3.16]
3.16
non-irritating level
NIL
greatest amount per surface area of an identified constituent that does not elicit irritation (3.12) to the tissue
at the contact site as determined by valid experimental or observational evidence
Note 1 to entry: The non-irritating level is usually expressed as milligram per centimetre squared per centimetre
2 2
squared (mg/cm ) or microgram per centimetre squared (μg/cm ).
[SOURCE: ISO 10993-17:2023, 3.17, modified — ‘usually’ and ‘milligram per centimetre squared per
centimetre squared (mg/cm ) or’ have been added to Note 1 to entry. ]
3.17
no observed adverse effect level
NOAEL
greatest concentration or amount of an identified constituent found by experiment or observation which
causes no detectable harm to health (3.9) to the target organism under defined conditions of exposure
Note 1 to entry: No observed adverse effect level is expressed in microgram per kilogram of body mass per day (μg/
kg/d).
[SOURCE: ISO 10993-17:2023, 3.18]
3.18
physiologically based pharmacokinetic modelling
PBPK modelling
system of modelling biological effects taking into account metabolic and pharmacokinetic differences among
species of animals
Note 1 to entry: Such data should be utilized whenever available and applicable to medical device anticipated exposure
duration.
3.19
residual
quantity of ethylene oxide, ethylene chlorohydrin or ethylene glycol that remains in or on the product after
ethylene oxide sterilization
3.20
safety
freedom from unacceptable risk
[SOURCE: ISO 14971:2019, 3.26]
3.21
simulated-use extraction
extraction using a method that simulates clinical use
Note 1 to entry: A simulated-use extraction is performed to estimate the type and amount of substances that are
expected to be released from a medical device during its clinical use. A simulated-use extraction is designed to
produce an extractables profile that represents the worst-case leachables profile, meaning that all leachables are also
extractables and the levels of all individual extractables are at least equal to the level of all individual leachables.
[SOURCE: ISO 10993-18:2020, 3.35]

ISO 10993-7:2026(en)
3.22
tolerable contact level
TCL
estimate of the surface-contact exposure to an identified constituent that is without appreciable irritation
(3.12)
Note 1 to entry: Tolerable contact level is expressed in microgram per centimetre squared (μg/cm ) of tissue at the
contact site.
[SOURCE: ISO 10993-17:2023, 3.25]
3.23
tolerable exposure
TE
product of the tolerable intake (3.24), the body mass and the concomitant exposure factor (3.4)
Note 1 to entry: Tolerable exposure is normally expressed in milligrams per day to the patient.
3.24
tolerable intake
TI
estimate of the daily exposure of an identified constituent over a specified time period (e.g. acute, subacute,
sub-chronic or chronic), on the basis of body mass, that is considered to be without appreciable harm to
health (3.9)
Note 1 to entry: Tolerable intake is normally expressed in microgram per kilogram of body mass per day (μg/kg/d). It
is derived to establish an allowable limit (3.2) for a medical device constituent.
[SOURCE: ISO 10993-17:2023, 3.26, modified — ‘normally’ has been added and ‘toxicological exposure limit’
has been replaced with ‘an allowable limit (3.2)’ in Note 1 to entry.]
3.25
toxicological risk assessment
determination of whether an exposure dose to a constituent can or cannot elicit appreciable
...