FprEN ISO 80601-2-74

SLOVENSKI STANDARD
oSIST prEN ISO 80601-2-74:2025
01-februar-2025
Medicinska električna oprema - 2-74. del: Posebne zahteve za osnovno varnost in
bistvene lastnosti za vlažilne sisteme dihalne opreme (ISO/DIS 80601-2-74:2024)
Medical electrical equipment - Part 2-74: Particular requirements for basic safety and
essential performance of respiratory humidifying equipment (ISO/DIS 80601-2-74:2024)
Medizinische elektrische Geräte - Teil 2-74: Besondere Festlegungen für die Sicherheit
einschließlich der wesentlichen Leistungsmerkmale von Anfeuchtersystemen für
Atemgase (ISO/DIS 80601-2-74:2024)
Appareils électromédicaux - Partie 2-74: Exigences particulières pour la sécurité de base
et les performances essentielles des équipements d'humidification respiratoire (ISO/DIS
80601-2-74:2024)
Ta slovenski standard je istoveten z: prEN ISO 80601-2-74
ICS:
11.040.10 Anestezijska, respiratorna in Anaesthetic, respiratory and
reanimacijska oprema reanimation equipment
oSIST prEN ISO 80601-2-74:2025 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN ISO 80601-2-74:2025

oSIST prEN ISO 80601-2-74:2025
DRAFT
International
Standard
ISO/DIS 80601-2-74
ISO/TC 121/SC 3
Medical electrical equipment —
Secretariat: ANSI
Part 2-74:
Voting begins on:
Particular requirements for basic 2024-12-06
safety and essential performance of
Voting terminates on:
2025-02-28
respiratory humidifying equipment
Appareils électromédicaux —
Partie 2-74: Exigences particulières pour la sécurité de base et
les performances essentielles des équipements d'humidification
respiratoire
ICS: 11.040.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
This document is circulated as received from the committee secretariat. IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This draft is submitted to a parallel vote in ISO and in IEC.
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 80601-2-74:2024(en)
oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
DRAFT
International
Standard
ISO/DIS 80601-2-74
ISO/TC 121/SC 3
Medical electrical equipment —
Secretariat: ANSI
Part 2-74:
Voting begins on:
Particular requirements for basic
safety and essential performance of
Voting terminates on:
respiratory humidifying equipment
Appareils électromédicaux —
Partie 2-74: Exigences particulières pour la sécurité de base et
les performances essentielles des équipements d'humidification
respiratoire
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
This draft is submitted to a parallel vote in ISO and in IEC.
INTERNATIONAL STANDARD UNTIL
© ISO 2024 PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
This document is circulated as received from the committee secretariat.
BEING ACCEPTABLE FOR INDUSTRIAL,
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
TECHNOLOGICAL, COMMERCIAL AND
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
USER PURPOSES, DRAFT INTERNATIONAL
or ISO’s member body in the country of the requester.
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
ISO copyright office
POTENTIAL TO BECOME STANDARDS TO
CP 401 • Ch. de Blandonnet 8 ISO/CEN PARALLEL PROCESSING
WHICH REFERENCE MAY BE MADE IN
CH-1214 Vernier, Geneva
NATIONAL REGULATIONS.
Phone: +41 22 749 01 11
RECIPIENTS OF THIS DRAFT ARE INVITED
Email: copyright@iso.org
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
Website: www.iso.org
RIGHTS OF WHICH THEY ARE AWARE AND TO
Published in Switzerland
PROVIDE SUPPORTING DOCUMENTATION.

Reference number
ISO/DIS 80601-2-74:2024(en)
ii
oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
1 Contents Page
2 Foreword . v
3 Introduction . vi
4 201.1 Scope, object and related standards . 1
5 201.2 Normative references . 3
6 201.3 Terms and definitions . 4
7 201.4 General requirements . 19
8 201.5 General requirements for testing of ME equipment . 22
9 201.6 Classification of ME equipment and ME systems . 24
10 201.7 ME equipment identification, marking and documents . 25
11 201.8 Protection against electrical hazards form ME equipment . 32
12 201.9 Protection against mechanical hazards of ME equipment and ME systems . 32
13 201.10 Protection against unwanted and excessive radiation hazards . 33
14 201.11 Protection against excessive temperatures and other hazards . 33
15 201.12 Accuracy of controls and instruments and protection against
16 hazardous outputs . 36
17 201.13 Hazardous situations and fault conditions for ME Equipment . 41
18 201.14 Programmable electrical medical systems (PEMS) . 42
19 201.15 Construction of ME equipment . 43
20 201.16 ME systems . 43
21 201. 16.2 Accompanying documents of an ME system . 43
22 201.17 Electromagnetic compatibility of ME equipment and ME systems . 44
23 201.101 Breathing system connectors and ports . 44
24 201.102 Requirements for the breathing system and accessories . 46
25 201.103 Liquid container . 47
26 201.104 Functional connection. 48
27 202 Electromagnetic disturbances — Requirements and tests . 48
28 206 Usability . 49
29 208 General requirements, tests and guidance for alarm systems in
30 medical electrical equipment and medical electrical systems . 50
31 211 Requirements for medical electrical equipment and medical electrical
32 systems used in the home healthcare environment . 51
33 Annex C (informative)  Guide to marking and labelling requirements for
34 ME equipment and ME systems . 52
35 Annex D (informative)  Symbols on marking. 57
36 Annex AA (informative)  Particular guidance and rationale . 59
37 Annex BB (normative)  Determination of the accuracy of the displayed measured gas
38 temperature . 78
39 Annex CC (normative)  Determination of the humidification output . 80
40 Annex DD (normative)  Specific enthalpy calculations . 85
41 Annex EE (normative)  Removable temperature sensors and mating ports . 87
42 Annex FF (normative)  Reference temperature sensor. 90
oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
43 FF.1 Test preparation . 90
44 Annex GG (informative)  Saturation vapour pressure . 93
45 Annex HH (informative)  Liquid fill port . 94
46 Annex II (informative)  Reference to the IMDRF essential principles and
47 labelling guidances . 97
48 Annex JJ (informative)  Terminology — Alphabetized index of defined terms . 101
49 Bibliography . 106
iv © ISO 2024 – All rights reserved

oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
51 Foreword
52 ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
53 (ISO member bodies). The work of preparing International Standards is normally carried out through ISO
54 technical committees. Each member body interested in a subject for which a technical committee has been
55 established has the right to be represented on that committee. International organizations, governmental and
56 non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International
57 Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
58 The procedures used to develop this document and those intended for its further maintenance are described in
59 the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO
60 documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC
61 Directives, Part 2 (see www.iso.org/directives).
62 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
63 rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights
64 identified during the development of the document will be in the Introduction and/or on the ISO list of patent
65 declarations received (see www.iso.org/patents).
66 Any trade name used in this document is information given for the convenience of users and does not constitute
67 an endorsement.
68 For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
69 related to conformity assessment, as well as information about ISO's adherence to the World Trade
70 Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
71 This document was prepared jointly by Technical Committee ISO/TC 121, Anaesthetic and respiratory
72 equipment, Subcommittee SC 3, Respiratory devices and related equipment used for patient care, and Technical
73 Committee IEC/TC 62, Medical equipment, software, and systems, Subcommittee SC 62D, Particular medical
74 equipment, software, and systems, in collaboration with the European Committee for Standardization (CEN)
75 Technical Committee CEN/TC 215, Respiratory and anaesthetic equipment, in accordance with the Agreement
76 on technical cooperation between ISO and CEN (Vienna Agreement).
77 This third edition cancels and replaces the second edition (ISO 80601-2-74:2021), which has been technically
78 revised.
79 The main changes compared to the previous edition are as follows:
80 — updated normative references;
81 — added requirements for the fill connector; and
82 — clarified system recovery requirements.
83 A list of all parts in the ISO 80601 series and the IEC 80601 series can be found on the ISO and IEC websites.
84 Any feedback or questions on this document should be directed to the user’s national standards body. A
85 complete listing of these bodies can be found at www.iso.org/members.html.
oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
86 Introduction
87 This document specifies requirements for respiratory humidifying equipment intended for use on patients in
88 home healthcare environment and in professional healthcare environment. Humidifiers are used to raise the
89 water content of gases delivered to patients. Gases available for medical use do not contain sufficient moisture
90 and can damage or irritate the respiratory tract or desiccate secretions of patients whose upper airways have
91 been bypassed. Inadequate humidity in the inspired gas can cause drying of the upper airway, or desiccation of
92 tracheo-bronchial secretions in the tracheal or tracheostomy tube, which can cause narrowing or even
[31] [45]
93 obstruction of the airway . Heat is employed to increase the water output of the humidifier.
94 In addition, many humidifiers utilize heated breathing tubes in order to increase operating efficiency and reduce
95 water loss (condensate) as well as heat loss in the breathing tube. Ventilator and anaesthesia breathing tubes in
96 common use might not withstand the heat generated by humidifiers and breathing tube heating mechanisms.
97 Many humidifier manufacturers use off-the-shelf electrical connectors for their electrically heated breathing
98 tubes. However, since different manufacturers have used the same electrical connector for different power
99 outputs, electrically heated breathing tubes can be physically, but not electrically, interchangeable. Use of
improper electrically heated breathing tubes has caused overheating, circuit melting, patient and operator
101 burns and fires. It was not found practical to specify the interface requirements for electrical connectors to
102 ensure compatibility between humidifiers and breathing tubes produced by different manufacturers.
103 Since the safe use of a humidifier depends on the interaction of the humidifier with its many accessories, this
104 document sets total system performance requirements up to the patient-connection port. These requirements
105 are applicable to accessories such as breathing tubes (both heated and non-heated), temperature sensors and
106 equipment intended to control the environment within these breathing tubes.
107 Humidification can also be used by respiratory support ME equipment to increase patient comfort and
108 compliance with the therapy. Examples are obstructive sleep apnoea and nasal high-flow therapy equipment.
109 The humidification output requirements of such ME equipment is less demanding as the patient’s upper airway
110 is not bypassed.
111 Humidifiers are commonly used with air and air-oxygen mixtures and any humidifier should be able to operate
112 with these gases. Care should be taken if using other gas mixes such as helium-oxygen mixtures, as the different
113 physical and thermal properties of these gases may disturb the operation of the humidifier.
In this document, the following print types are used:
115 — Requirements and definitions: roman type;
116 — Test specifications and terms defined in Clause 3 of the general standard, in this document or as noted: italic
117 type;
118 — Informative material appearing outside of tables, such as notes, examples and references: in smaller type. Normative
119 text of tables is also in a smaller type;
120 In referring to the structure of this document, the term
121 — “clause” means one of the five numbered divisions within the table of contents, inclusive of all subdivisions
122 (e.g. Clause 201 includes subclauses 201.7, 201.8, etc.);
123 — “subclause” means a numbered subdivision of a clause (e.g. 201.7, 201.8 and 201.9 are all subclauses of
124 Clause 201).
125 References to clauses within this document are preceded by the term “Clause” followed by the clause number.
126 References to subclauses within this document are by number only.
127 In this document, the conjunctive “or” is used as an “inclusive or” so a statement is true if any combination of
128 the conditions is true.
vi © ISO 2024 – All rights reserved

oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
129 For the purposes of this document, the auxiliary verb:
130 — “shall” indicates a requirement;
131 — “should” indicates a recommendation;
132 — “may” indicates a permission;
133 — "can" is used to describe a possibility or capability; and;
134 — "must" is used to express an external constraint.
135 Annex C contains a guide to the marking and labelling requirements in this document.
136 Annex D contains a summary of the symbols referenced in this document.
oSIST prEN ISO 80601-2-74:2025

oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
DRAFT INTERNATIONAL STANDARD
139 Medical electrical equipment —
140 Part 2-74:
141 Particular requirements for basic safety and essential performance
142 of respiratory humidifying equipment
143 201.1 Scope, object and related standards
144 Clause 1 of IEC 60601-1:2005+AMD1:2012+AMD2:2020 applies, except as follows.
145 NOTE The general standard is IEC 60601-1:2005+AMD1:2012+AMD2:2020.
146 201.1.1 Scope
147 Replacement:
148 NOTE 1 There is guidance or rationale for this subclause contained in Clause AA.2.
149 This document applies to the basic safety and essential performance of a humidifier, also hereafter referred to
150 as ME equipment, in combination with its accessories, the combination also hereafter referred to as ME system.
151 This document is also applicable to those accessories intended by their manufacturer to be connected to a
152 humidifier where the characteristics of those accessories can affect the basic safety or essential performance of
153 the humidifier.
154 EXAMPLE 1 Heated breathing tubes (heated-wire breathing tubes) or ME equipment intended to control these heated
155 breathing tubes (heated breathing tube controllers).
156 NOTE 2 Heated breathing tubes and their controllers are ME equipment and are subject to the requirements of
157 IEC 60601-1.
158 NOTE 3 ISO 5367 specifies other safety and performance requirements for breathing tubes.
159 This document includes requirements for the different medical uses of humidification, such as invasive
160 ventilation, non-invasive ventilation, nasal high-flow therapy, and obstructive sleep apnoea therapy, as well as
161 humidification therapy for tracheostomy patients.
162 NOTE 4 A humidifier can be integrated into other equipment. When this is the case, the requirements of the other
163 equipment also apply to the humidifier.
164 EXAMPLE 2 Heated humidifier incorporated into a critical care ventilator where ISO 80601-2-12 also applies.
165 EXAMPLE 3 Heated humidifier incorporated into a homecare ventilator for dependent patients where ISO 80601-2-72
166 also applies.
167 EXAMPLE 4 Heated humidifier incorporated into sleep apnoea therapy equipment where ISO 80601-2-70 also applies.
168 EXAMPLE 5 Heated humidifier incorporated into ventilatory support equipment where either ISO 80601-2-79 or
169 ISO 80601-2-80 also apply.
170 EXAMPLE 6 Heated humidifier incorporated into respiratory high-flow therapy equipment where ISO 80601-2-90 also
171 applies.
oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
172 This document also includes requirements for an active HME (heat and moisture exchanger), ME equipment
173 which actively adds heat and moisture to increase the humidity level of the gas delivered from the HME to the
174 patient. This document is not applicable to a passive HME, which returns a portion of the expired moisture and
175 heat of the patient to the respiratory tract during inspiration without adding heat or moisture.
176 NOTE 5 ISO 9360-1 and ISO 9360-2 specify safety and performance requirements for a passive HME.
177 NOTE 6 If a clause or subclause is specifically intended to be applicable to ME equipment only, or to ME systems only,
178 the title and content of that clause or subclause will say so. If that is not the case, the clause or subclause applies both to
179 ME equipment and to ME systems, as relevant.
180 Hazards inherent in the intended physiological function of ME equipment or ME systems within the scope of this
181 document are not covered by specific requirements in this document except in
182 IEC 60601-1:2005+AMD1:2012+AMD2:2020, 7.2.13 and 8.4.1.
183 NOTE 7 Additional information can be found in IEC 60601-1:2005+AMD1:2012+AMD2:2020, 4.2.
184 This document does not specify the requirements for cold pass-over or cold bubble-through humidification
185 devices, the requirements for which are given in ISO 20789.
186 This document is not applicable to equipment commonly referred to as “room humidifiers” or humidifiers used
187 in heating, ventilation and air conditioning systems, or humidifiers incorporated into infant incubators to
188 humidify the chamber air (i.e., are not directly connected to the patient).
189 This document is not applicable to nebulizers used for the delivery of a drug to patients.
190 NOTE 8 ISO 27427 specifies the safety and performance requirements for nebulizers and ISO 80601-2-94 for
191 inhalational therapy nebulizer equipment.
192 201.1.2 Object
193 Replacement:
194 The object of this document is to establish particular basic safety and essential performance requirements for a
195 humidifier, as defined in 201.3.241, and its accessories.
196 Accessories are included because the combination of the humidifier and the accessories needs to be adequately
197 safe. Accessories can have a significant impact on the basic safety or essential performance of a humidifier.
198 NOTE 1 This document has been prepared to address the relevant essential principles and labelling guidances of the
199 International Medical Devices Regulators Forum (IMDRF) as indicated in Annex II.
200 NOTE 2 This document has been prepared to address the relevant general safety and performance requirements of
201 European regulation (EU) 2017/745.
202 201.1.3 Collateral standards
203 Addition (add after existing text):
204 This document refers to those applicable collateral standards that are listed in Clause 2 of the general standard
205 and in 201.2 of this document.
206 IEC 60601-1-2:2014+AMD1:2020, IEC 60601-1-6:2010+AMD1:2013+AMD2:2020,
207 IEC 60601-1-8:2006+AMD1:2012+AMD2:2020 and IEC 60601-1-11:2015+AMD1:2020 apply as modified in
208 Clauses 202, 206, 208 and 211, respectively. IEC 60601-1-3:2008+AMD1:2013+AMD2:2021 and IEC 60601-1-
209 9:2007+AMD1:2013+AMD2:2020 do not apply. All other published collateral standards in the IEC 60601-1
210 series apply as published.
211 201.1.4 Particular standards
Replacement:
2 © ISO 2024 – All rights reserved

oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
213 In the IEC 60601 series, particular standards define basic safety and essential performance requirements, and
214 may modify, replace or delete requirements contained in the general standard and collateral standards as
215 appropriate for the particular ME equipment under consideration.
216 A requirement of a particular standard takes priority over the general standard.
217 For brevity, IEC 60601-1:2005+AMD1:2012+AMD2:2020 is referred to in this document as the general
218 standard. Collateral standards are referred to by their document number.
219 The numbering of clauses and subclauses of this document corresponds to that of the general standard with
220 the prefix “201” (e.g. 201.1 in this document addresses the content of Clause 1 of the general standard) or
221 applicable collateral standard with the prefix “20x”, where x is the final digit(s) of the collateral standard
222 document number (e.g. 202.4 in this document addresses the content of Clause 4 of the IEC 60601-1-2 collateral
223 standard, 208.6 in this document addresses the content of Clause 6 of the IEC 60601-1-8 collateral standard,
224 etc.). The changes to the text of the general standard are specified by the use of the following words:
225 “Replacement” means that the clause or subclause of the general standard or applicable collateral standard is
226 replaced completely by the text of this document.
227 “Addition” means that the text of this document is additional to the requirements of the general standard or
228 applicable collateral standard.
229 “Amendment” means that the clause or subclause of the general standard or applicable collateral standard is
230 amended as indicated by the text of this document.
231 Clauses, subclauses, figures or tables which are additional to those of the general standard are numbered
232 starting from 201.101. However, due to the fact that definitions in the general standard are numbered 3.1
233 through 3.154, additional definitions in this document are numbered beginning from 201.3.201. Additional
234 annexes are lettered AA, BB, etc., and additional items aa), bb), etc.
235 Subclauses, figures or tables which are additional to those of a collateral standard are numbered starting from
236 20x, where “x” is the number of the collateral standard, e.g. 202 for IEC 60601-1-2, 211 for IEC 60601-1-11, etc.
237 The term “this document” is used to make reference to the general standard, any applicable collateral standards
238 and this particular document taken together.
239 Where there is no corresponding clause or subclause in this document, the clause or subclause of the general
240 standard or applicable collateral standard, although possibly not relevant, applies without modification; where
241 it is intended that any part of the general standard or applicable collateral standard, although possibly relevant,
242 is not to be applied, a statement to that effect is given in this document.
243 201.2 Normative references
244 The following documents are referred to in the text in such a way that some or all of their content constitutes
245 requirements of this document. For dated references, only the edition cited applies. For undated references, the
246 latest edition of the referenced document (including any amendments) applies.
247 Clause 2 of IEC 60601-1:2005+AMD1:2012+AMD2:2020 applies, except as follows.
248 Replacement:
249 Addition:
250 ISO 3744:2010, Acoustics — Determination of sound power levels and sound energy levels of noise sources using
251 sound pressure — Engineering methods for an essentially free field over a reflecting plane
252 ISO 5356-1:2015, Anaesthetic and respiratory equipment — Conical connectors — Part 1: Cones and sockets
253 ISO 5359:2014+AMD1:2017, Anaesthetic and respiratory equipment — Low-pressure hose assemblies for use
254 with medical gases
oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
255 ISO 5367:2023, Anaesthetic and respiratory equipment — Breathing sets and connectors
256 ISO 7396-1:2016+AMD1:2017, Medical gas pipeline systems — Part 1: Pipeline systems for compressed medical
257 gases and vacuum
258 ISO 14937:2009, Sterilization of health care products — General requirements for characterization of a
259 sterilizing agent and the development, validation and routine control of a sterilization process for medical devices
260 ISO 17664-1:2021, Processing of health care products — Information to be provided by the medical device
261 manufacturer for the processing of medical devices — Part 1: Critical and semi-critical medical devices
262 ISO 17664-2:2021, Processing of health care products — Information to be provided by the medical device
263 manufacturer for the processing of medical devices — Part 2: Non-critical medical devices
264 ISO 18562-1:2024, Biocompatibility evaluation of breathing gas pathways in healthcare applications — Part 1:
265 Evaluation and testing within a risk management process
266 ISO 20417:— , Medical devices — Information to be supplied by the manufacturer
267 ISO 80369-1:— , Small-bore connectors for liquids and gases in healthcare applications — Part 1: General
268 requirements
269 ISO 80369-2:2024, Small-bore connectors for liquids and gases in healthcare applications — Part 2: Connectors
270 for breathing systems and driving gases applications
271 IEC 60601-1:2005+AMD1:2012+AMD2:2020, Medical electrical equipment — Part 1: General requirements for
272 basic safety and essential performance
273 IEC 60601-2-19:2020, Medical electrical equipment — Part 2-19: Particular requirements for the basic safety and
274 essential performance of infant incubators
275 IEC 62570:2014, Standard practice for marking medical devices and other items for safety in the magnetic
276 resonance environment
277 IEC 81001-5-1:2021, Health software and health IT systems safety, effectiveness and security — Part 5-1: Security
278 — Activities in the product life cycle
279 IEC Guide 115:2023, Application of uncertainty of measurement to conformity assessment activities in the
280 electrotechnical sector
281 201.3 Terms and definitions
282 For the purposes of this document, the terms and definitions given in
283 IEC 60601-1-8:2006+AMD1:2012+AMD2:2020 and the following apply.
284 ISO and IEC maintain terminological databases for use in standardization at the following addresses:
285 — ISO Online browsing platform: available at https://www.iso.org/obp
286 — IEC Electropedia: available at https://www.electropedia.org/
287 NOTE An alphabetized index of defined terms is found in Annex JJ.
Under preparation. Stage at the time of publication: ISO/DIS 20417:2024.
Under preparation. Stage at the time of publication: ISO/FDIS 80369-1:2024.
4 © ISO 2024 – All rights reserved

oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
288 201.3.201
289 absolute humidity
290 mass of water vapour present in a unit volume of gas
291 Note 1 to entry: In respiratory applications absolute humidity is commonly represented in units of milligrams per litre or
292 grams per cubic metre, with volume expressed at BTPS condition.
293 Note 2 to entry: See also relative humidity.
294 [SOURCE: ISO 4135:2022, 3.1.1.1]
295 201.3.202
296 accompanying information
297 information accompanying or marked on a medical device or accessory for the user or those accountable for the
298 installation, use, processing, maintenance, decommissioning and disposal of the medical device or accessory,
299 particularly regarding safe use
300 Note 1 to entry: The accompanying information shall be regarded as part of the medical device or accessory.
301 Note 2 to entry: The accompanying information can consist of the label, marking, instructions for use, technical description,
302 installation manual, quick reference guide, etc.
303 Note 3 to entry: Accompanying information is not necessarily a written or printed document but could involve auditory,
304 visual, or tactile materials and multiple media types (e.g. CD/DVD-ROM, USB stick, website).
305 [SOURCE: ISO 20417:2021, 3.2, modified — deleted note 4.]
306 201.3.203
307 active HME
308 humidifier where water, water vapour or heat is actively added to the HME to increase the humidity level of the
309 gas delivered from the HME to the patient
310 [SOURCE: ISO 4135:2022, 3.7.2.3, modified —replaced 'device' with 'humidifier'.]
311 201.3.204
312 aerosol
313 suspension of liquid or solid particles in a gas
314 [SOURCE: ISO 4135:2022, 3.1.1.3]
315 201.3.205
316 airway device
317 device intended to provide a gas pathway to and from the patient’s airway
318 [SOURCE: ISO 4135:2022, 3.8.1.2]
319 201.3.206
320 airway pressure
321 P
AW
322 pressure at the patient-connection port or at the distal outlet of the equipment where there is no patient-
323 connection port
324 Note 1 to entry: The airway pressure can be derived from pressure measurements made anywhere within the equipment.
325 [SOURCE: ISO 4135:2022, 3.1.4.41.1]
oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
326 201.3.207
327 alarm limit
328 threshold used by an alarm system to determine an alarm condition
329 [SOURCE: IEC 60601-1-8:2006+AMD1:2012+AMD2:2020, 3.3]
330 201.3.208
331 alarm paused
332 state of limited duration in which the alarm system or part of the alarm system does not generate alarm signals
333 [SOURCE: IEC 60601-1-8:2006+AMD1:2012+AMD2:2020, 3.5]
334 201.3.209
335 alarm setting
336 alarm system configuration, including but not limited to:
337 – alarm limits;
338 – the characteristics of any alarm signal inactivation states; and
339 – the values of variables or parameters that determine the function of the alarm system
340 Note 1 to entry: Some algorithmically-determined alarm settings can require time to be determined or re-determined.
341 [SOURCE: IEC 60601-1-8:2006+AMD1:2012+AMD2:2020, 3.8]
342 201.3.210
343 artificial ventilation
344 intermittent elevation of the pressure in the patient's airway relative to that in the lungs by external means with
345 the intention of augmenting, or totally controlling, the ventilation of a patient
346 EXAMPLE Means used to provide artificial ventilation are manual resuscitation; mouth-to-mouth resuscitation; automatic
347 ventilation; mechanical ventilation.
348 Note 1 to entry: Common classifications of areas of application of artificial ventilation are: emergency; transport; home-
349 care; anaesthesia; critical care; rehabilitation.
350 Note 2 to entry: Classifications used to denote means used for artificial ventilation include: positive-pressure; negative-
351 pressure; gas-powered; operator-powered; electrically-powered.
352 Note 3 to entry: Negative-pressure ventilation elevates the relative pressure in the airway by intermittently lowering the
353 pressure in the lungs.
354 [SOURCE: ISO 19223:2019, 3.1.10]
355 201.3.211
356 attack
357 attempt to destroy, expose, alter, disable, steal or gain unauthorized access to or make unauthorized use of an
358 asset
359 [SOURCE: IEC 81001-5-1:2021, 3.5]
360 201.3.212
361 audio paused
362 state of limited duration in which the alarm system or part of the alarm system does not generate an auditory
363 alarm signal
364 [SOURCE: IEC 60601-1-8:2006+AMD1:2012+AMD2:2020, 3.13]
6 © ISO 2024 – All rights reserved

oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
365 201.3.213
366 BAP
367 quantity by which the baseline airway pressure is set to be positively offset from the ambient pressure
368 [SOURCE: ISO 19223:2019, 3.10.2, modified — deleted notes.]
369 201.3.214
370 biocompatibility
371 ability to be in contact with a living system without producing an unacceptable adverse effect
372 Note 1 to entry: Medical devices may produce some level of adverse effect, but that level may be determined to be
373 acceptable when considering the benefits provided by the medical device.
374 [SOURCE: ISO 18562-1:2024, 3.6]
375 201.3.215
376 body temperature and pressure, saturated
377 BTPS
378 ambient atmospheric pressure, at a temperature of 37 °C, and at a relative humidity of 100 %
379 [SOURCE: ISO 4135:2022, 3.1.1.7]
380 201.3.216
381 breathing system
382 pathways through which gas flows to or from the patient at respiratory pressures and continuously or
383 intermittently in fluid communication with the patient’s respiratory tract during any form of artificial
384 ventilation or respiratory therapy
385 [SOURCE: ISO 4135:2022, 3.6.1.1, modified —deleted the notes to entry.]
386 201.3.217
387 breathing system filter
388 BSF
389 device intended to reduce transmission of particulates, including microorganisms, in breathing systems
390 [SOURCE: ISO 23328-2:2002, 3.1]
391 201.3.218
392 breathing tube
393 non-rigid tube used to convey gases or vapours within the operator-detachable section of a breathing system
394 [SOURCE: ISO 4135:2022, 3.1.4.4, modified —replaced “user” with “operator” deleted note.]
395 201.3.219
396 cleaning
397 removal of contaminants to the extent necessary for further processing or for intended use
398 Note 1 to entry: Cleaning consists of the removal of adherent soil (e.g. blood, protein substances, and other debris) from
399 the surfaces, crevices, serrations, joints, and lumens of a medical device by a manual or automated process that prepares
400 the items for safe handling or further processing.
401 [SOURCE: ISO 17664-2:2021, 3.1, modified — replaced 'and/or' with 'or'.]
oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
402 201.3.220
connector
404 fitting to join two or more components
405 EXAMPLE Connectors for low-pressure hose assembly are any of a range of mating components intended to maintain gas
406 specificity by the allocation of a set of different diameters to the mating connectors for each particular gas.
407 [SOURCE: ISO 4135:2022, 3.1.4.5]
408 201.3.221
409 CPAP
410 continuous positive airway pressure
411 ventilation-mode or sleep-apnoea breathing-therapy mode in which the patient breathes continuously at a set
412 airway-pressure level, above ambient pressure
413 [SOURCE: ISO 19223:2019, 3.11.15, modified — deleted notes.]
414 201.3.222
415 cybersecurity
416 state where information and systems are protected from unauthorized activities, such as access, use, disclosure,
417 disruption, modification, or destruction to a degree that the related risks to violation of confidentiality, integrity,
418 and availability are maintained at an acceptable level throughout the life cycle
419 [SOURCE: IEC 81001-5-1:2021, 3.30]
420 201.3.223
421 delivered gas temperature
422 temperature of the gas, or aerosol, or both, being delivered to a patient, referenced to the patient-connection
423 port
424 [SOURCE: ISO 4135:2022, 3.1.1.13]
425 201.3.224
426 disinfection
427 process to reduce the number of viable microorganisms to a level previously specified as being appropriate for
428 a defined purpose
429 [SOURCE: ISO 17664-1:2021, 3.3]
430 201.3.225
431 distributed alarm system
432 DAS
433 alarm system that involves more than one item of equipment of a me system intended for delivery of alarm
434 conditions with technical confirmation
435 Note 1 to entry: The parts of a distributed alarm system can be widely separated in distance.
436 Note 2 to entry: A distributed alarm system is intended to notify operators of the existence of an alarm condition.
437 Note 3 to entry: Technical confirmation means that each element of a distributed alarm system confirms or guarantees the
438 successful delivery of the alarm condition to the next element or appropriate technical alarm conditions are created.
439 [SOURCE: IEC 60601-1-8:2006+AMD1:2012+AMD2:2020, 3.17]
8 © ISO 2024 – All rights reserved

oSIST prEN ISO 80601-2-74:2025
ISO/DIS 80601-2-74:2024(en)
440 201.3.226
441 emergency medical services environment
442 EMS environment
443 actual conditions and settings, in which operators interact with the ME equipment or ME system, in and around
444 the scene of an emergency outside of a professional healthcare facility where a patient can be given medical
445 care, basic or advanced life support as well as during professional transport to a professional healthcare facility
446 or between professional healthcare facilities
447 EXAMPLE 1 Responding to and providing life support at the scene of an emergency to a patient reported as experiencing
448 injury or illness in a pre-hospital setting, and transporting the patient, while continuing such life support care, to an
449 appropriate professional healthcare facility for further care.
450 EXAMPLE 2 Providing monitoring, treatment or diagnosis during transport between professional healthcare facilities.
451 Note 1 to entry: The EMS environment is not considered to be part of the professional healthcare environment.
452 Note 2 to entry: Use of equipment intended for the EMS environment and temporarily used in the home healthcare
453 environment by emergency medical personnel is considered use in the EMS environment.
454 Note 3 to entry: The operators of equipment intended for the EMS environment are presumed to be healthcare professional
455 operators.
456 Note 4 to entry: Emergency medical services are known by various names in different countries and regions.
457 Note 5 to entry: Transport includes road, rotary and fixed-wing ambulances.
458 [SOURCE: IEC 60601-1-12:2014+AMD1:2020, 3.1, modified —replaced “professional medical personnel or
459 personnel with relevant specialized training” with “healthcare professional operators” and replaced original
460 note 3 with new note 1.]
461 201.3.227
462 essential function
463 function or capability that is required to maintain basic safety, essential performance, a minimum of clinical
464 functionality as specified by the manufacturer, and operational availability for the medical device
465 Note 1 to entry: Essential functions include, but are not limited to, the safety instrumented function (basic safety and
466 essential performance), the control function and the availability of urgently needed functions and such allowing the
467 operator to view and manipulate the medical device safely with the most urgently needed performance (operational
468 availability). The loss of essential function is commonly termed loss of protection, loss of control and loss of view
469 respectively.
470 Note 2 to entry: The term is derived from IEC 62443-4-2:2019, 3.1.20, and has been refined for the purpose and scope of
471 this document.
472 [SOURCE: IEC/TR 60601-4-5:2021, 3.10]
473 201.3.228
474 essential principles
475 essential principles of safety and performance
476 fundamental high-level requirements that when complied with ensure a medical device is safe and performs as
477 intended
478 [SOURCE: ISO 16142-1:2016, 3.3]
...