oSIST prEN ISO 9360-2:2026
(Main)Heat and moisture exchangers, and breathing system filters for respired gases - Part 2: Measurement of moisture loss (ISO/DIS 9360-2:2026)
General Information
- Abstract
- Status
- Not Published
- Public Enquiry End Date
- 30-Oct-2026
- Technical Committee
- VAZ - Healthcare
- Current Stage
- 4020 - Public enquire (PE) (Adopted Project)
- Start Date
- 04-Sep-2026
- Due Date
- 22-Jan-2027
Overview
oSIST prEN ISO 9360-2:2026 is an international standard that specifies methods for measuring moisture loss in heat and moisture exchangers (HMEs) and breathing system filters (HMEFs and BSFs) for respired gases. Developed under ISO/TC 121/SC 2, this draft standard provides requirements and guidelines essential for evaluating the humidification performance of devices used in healthcare respiratory systems. This standard is critical for manufacturers, testing laboratories, and healthcare providers who rely on accurate humidification to support patient safety and comfort during anesthesia and mechanical ventilation.
Key Topics
Scope of Application
- Measurement of moisture loss in HMEs and HMEFs, including those with and without a machine port
- Applicable to devices used with patients whose tidal volume is equal to or greater than 250 mL
- Inclusion of system filters (BSFs) that contribute moisture to inspired gases
Testing Methodology
- Standardized apparatus and test conditions for consistent measurement across different devices and manufacturers
- Simulated respiratory cycles using a bidirectional flow generator and a humidity generator
- Requirements for test temperature, humidity, and tidal volumes
Performance Metrics
- Quantification of moisture conservation based on loss measured from the test setup
- Comparative data generated to support product selection and regulatory submissions
Calibration and Validation
- Use of a calibration HME to validate test apparatus performance
- Defined acceptable ranges for moisture loss to ensure repeatability and accuracy
Applications
Heat and humidity exchange in respiratory care:
The techniques described in oSIST prEN ISO 9360-2:2026 are fundamental in:
Design and Quality Control:
- Manufacturers use the measurement methods to develop and validate HMEs and filters for optimal humidification.
- Ensures devices meet the necessary performance criteria before market release.
Regulatory Compliance:
- Testing laboratories adopt the standard to provide results required for market approval and product certification.
- Supports evidence-based claims for product performance in humidification of respired gases.
Clinical Safety and Effectiveness:
- Healthcare providers depend on devices tested to this standard to ensure patients receive adequately humidified air during mechanical ventilation or spontaneous breathing via tracheostomy.
- Reduces risks related to airway dryness, improving patient comfort and reducing the likelihood of complications.
Comparative Product Assessment:
- Enables the direct comparison of moisture loss performance across products, supporting procurement and clinical decision-making.
Related Standards
Understanding moisture loss measurement in respiratory humidification devices involves multiple interconnected standards:
ISO 9360-1:
Heat and moisture exchangers, and breathing system filters for respired gases - Part 1: Common requirements. This document sets general requirements and is foundational to Part 2.ISO 23328-1 and ISO 23328-2 (Superseded):
Earlier standards for breathing system filters, now revised and incorporated into the ISO 9360 series.ISO TS 24172:
Describes alternative test methods for heat and moisture exchangers.ISO 5356-1:
Specifies conical connectors used in respiratory and anaesthetic equipment, referenced for apparatus construction.ISO 80601-2-74:
Covers active humidification devices, complementary to the scope of ISO 9360-2.
Practical Value
Compliance with oSIST prEN ISO 9360-2:2026 ensures the effective measurement of moisture loss in respiratory humidification devices. Adherence to this international standard improves product reliability and patient outcomes, facilitates regulatory approvals, and enhances clinical trust in HME, HMEF, and BSF products. This makes it an essential document for anyone involved in respiratory care equipment manufacturing, testing, or clinical use.
Relations
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 19-Feb-2025
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Frequently Asked Questions
oSIST prEN ISO 9360-2:2026 is a draft published by the Slovenian Institute for Standardization (SIST). Its full title is "Heat and moisture exchangers, and breathing system filters for respired gases - Part 2: Measurement of moisture loss (ISO/DIS 9360-2:2026)". This standard covers: L'ISO 9360-2:2001 spécifie certaines exigences et méthodes d'essai relatives aux échangeurs de chaleur et d'humidité (ECH) sans orifice de raccordement côté «appareil», y compris ceux équipés de filtres pour systèmes respiratoires. Ces dispositifs sont destinés à humidifier les gaz respirés par les patients trachéotomisés ayant un volume courant supérieur ou égal à 250 ml.
L'ISO 9360-2:2001 spécifie certaines exigences et méthodes d'essai relatives aux échangeurs de chaleur et d'humidité (ECH) sans orifice de raccordement côté «appareil», y compris ceux équipés de filtres pour systèmes respiratoires. Ces dispositifs sont destinés à humidifier les gaz respirés par les patients trachéotomisés ayant un volume courant supérieur ou égal à 250 ml.
oSIST prEN ISO 9360-2:2026 is classified under the following ICS (International Classification for Standards) categories: 11.040.10 - Anaesthetic, respiratory and reanimation equipment. The ICS classification helps identify the subject area and facilitates finding related standards.
oSIST prEN ISO 9360-2:2026 has the following relationships with other standards: It is inter standard links to SIST EN ISO 12855:2022, SIST EN ISO 12855:2025, SIST EN ISO 9360-2:2009. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
oSIST prEN ISO 9360-2:2026 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-oktober-2026
Izmenjevalniki toplote in vlage ter filtri dihalnih sistemov za dihalne pline - 2. del:
Merjenje izgube vlage (ISO/DIS 9360-2:2026)
Heat and moisture exchangers, and breathing system filters for respired gases - Part 2:
Measurement of moisture loss (ISO/DIS 9360-2:2026)
Anästhesie- und Beatmungsgeräte - Wärme- und Feuchtigkeitsaustauscher und
Atemschutzfilter (HMEF) zur Anfeuchtung von Atemgasen beim Menschen - Teil 2:
Messung von Feuchtigkeitsverlusten (ISO/DIS 9360-2:2026)
Titre manque — Partie 2: Titre manque
Ta slovenski standard je istoveten z: prEN ISO 9360-2
ICS:
11.040.10 Anestezijska, respiratorna in Anaesthetic, respiratory and
reanimacijska oprema reanimation equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
DRAFT
International
Standard
ISO/DIS 9360-2
ISO/TC 121/SC 2
Heat and moisture exchangers, and
Secretariat: ANSI
breathing system filters for respired
Voting begins on:
gases —
2026-08-20
Part 2:
Voting terminates on:
2026-11-12
Measurement of moisture loss
ICS: 11.040.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document has not been edited by the ISO Central Secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 9360-2:2026(en)
DRAFT
ISO/DIS 9360-2:2026(en)
International
Standard
ISO/DIS 9360-2
ISO/TC 121/SC 2
Heat and moisture exchangers, and
Secretariat: ANSI
breathing system filters for respired
Voting begins on:
gases —
2026-08-20
Part 2:
Voting terminates on:
2026-11-12
Measurement of moisture loss
ICS: 11.040.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document has not been edited by the ISO Central Secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BE CONSIDERED IN THE LIGHT OF THEIR
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NATIONAL REGULATIONS.
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RECIPIENTS OF THIS DRAFT ARE INVITED
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TO SUBMIT, WITH THEIR COMMENTS,
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NOTIFICATION OF ANY RELEVANT PATENT
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Published in Switzerland Reference number
ISO/DIS 9360-2:2026(en)
ii
ISO/DIS 9360-2:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Measurement of moisture loss . 2
4.1 Principle .2
4.2 Test apparatus.2
4.3 Test conditions .8
4.4 Procedure .8
5 Measurement of moisture loss from HME/HMEFs without a machine port .10
5.1 Principle .10
5.2 Test apparatus.10
5.3 Test conditions .10
5.4 Procedure .10
Annex A (informative) Lists of parts and specifications in Figure 1 and Figure 2.13
Annex B (informative) Rationale .15
Bibliography . 17
iii
ISO/DIS 9360-2:2026(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 documents 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.
International Standard ISO 9360-2 was prepared by Technical Committee ISO/TC 121, Anaesthetic and
respiratory equipment, Subcommittee SC 2, Airway devices and related equipment.
ISO 9360 consists of the following parts, under the general title Breathing system filters for anaesthetic and
respiratory use:
— Part 1: Common requirements
— Part 2: Measurement of moisture loss
— Part 3: Measurement of filtration performance
These parts technically revise and replace ISO 9360-1:2000, ISO 9360-2:2001, ISO 23328-1:2008 and
ISO 23328-2:2009.
These parts are a combination of the above standards with new and modified requirements, in particular:
— Part 1 combines requirements from ISO 9360-1:2000 and ISO 23328-2:2009
— Part 2 combines requirements from ISO 9360-1:2000 and ISO 9360-2:2001
— Part 3 are requirements from ISO 23328-1:2008
Changes from the previous standards are:
— Corrected dimensions for the calibration HME and heated water bath side view
iv
ISO/DIS 9360-2:2026(en)
Introduction
The gases generally available for medical use lack sufficient moisture to be physiologically acceptable to
the respiratory tract of patients. Heat and moisture exchangers (HME) are used to raise the water content
and the temperature of the gas delivered to the respiratory tract of spontaneously and non spontaneously
breathing patients. HMEs are intended to form part of a ventilator breathing system. HME's are primarily
placed between the patient interface (e.g. Tracheal or Tracheostomy tube) and the anaesthesia or ventilator
breathing set. HME's are also intended for use with tracheostomy tubes where the HME is not designed to
connect to an anaesthesia or ventilator breathing set.
v
DRAFT International Standard ISO/DIS 9360-2:2026(en)
Heat and moisture exchangers, and breathing system filters
for respired gases —
Part 2:
Measurement of moisture loss
1 Scope
This document specifies requirements for the measurement of moisture loss from heat and moisture
exchangers (HMEs), including those incorporating breathing system filters (HMEFs), intended for the
humidification of respired gases for use primarily with patients with a tidal volume equal to or greater than
250 ml.
Breathing system filters (BSF) are also included in scope, as these devices do some amount of moisture to
inspired gases.
This document also includes requirements for the measurement of moisture loss from HMEs for use with
tracheostomized patients that do not have a machine port and having minimum tidal volumes of 250 mL.
Active HMEs are excluded from this document, the requirements for active HMEs are included in
[1]
ISO 80601-2-74:2026 .
NOTE 1 Wherever the term “device” is used in this document, it may either refer to HME, HMEF or BSF.
*** Add rationale why 250ml lower limit***
NOTE 2 HMEs, HMEFs that do not have a machine port for connection to a breathing tube are intended for patients
who are spontaneously breathing via a tracheostomy and do not require mechanical ventilation.
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 5356-1:2015, Anaesthetic and respiratory equipment — Conical connectors — Part 1: Cones and sockets
ISO 9360-1: 202X Heat and moisture exchangers, and breathing system filters for respired gases — Part 1:
Common requirements
ISO TS 24172, Alternative test method for heat and moisture exchangers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 9360-1: 202X 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/
ISO/DIS 9360-2:2026(en)
NOTE The terms given in Clause 3 are delineated throughout the text in italics.
4 Measurement of moisture loss
NOTE There is guidance or rationale for this subclause contained in Annex B.
4.1 Principle
The performance of the device shall be measured by recording the mass of water lost from the test apparatus
specified in 4.2.
NOTE An alternative method to determine heat and moisture exchanging efficiency can be found in ISO TS 24172.
4.2 Test apparatus
NOTE There is guidance or rationale for this subclause contained in Annex B.
The test apparatus (Figure 1) shall comprise the following components.
a) A bidirectional flow generator, which is a mechanically driven piston used to produce a flow having a
sinusoidal waveform.
b) A Humidity generator (HG), consisting of
1) a heated water bath (Figure 2) through which air is bubbled in both directions;
2) a rigid cylindrical reservoir (Figure 3) with a maximum volume of 7 L and a diameter of
approximately 150 mm, containing a 2 L reservoir bag;
3) a thermally insulated chamber (Figure 4), which contains the water bath, the reservoir and a heat
source.
c) An air delivery system (Figure 5), consisting of a T-piece with an internal diameter greater than 15 mm,
and an exhaust tube at least 200 mm in length.
d) Weighing equipment, with an accuracy of ± 0,1 g or better in the range of the mass to be measured.
e) Flowrate measuring equipment, with an accuracy of at least 5 % of the reading.
f) Calibration HME (Figure 6) consisting of a housing containing 81 polyvinyl chloride (PVC) tubes
arranged in a 9 × 9 array, each with an internal diameter of 2 mm, an external diameter of 4 mm, and a
length of 50 mm.
When the apparatus has been constructed and operated as specified in 4.4 the moisture loss from the
humidity generator with the calibration HME will be as shown in Table 2.
ISO/DIS 9360-2:2026(en)
Dimensions in millimetres
Key
1 to 19 see Annex A
20 sine wave generator inlet
21 air outlet
22 dry air supply 23 ± 1 °C, < 1 mg H O per litre air
23 weighing equipment
Figure 1 — Test apparatus side view
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