ISO 80601-2-74:2017

INTERNATIONAL ISO
STANDARD 80601-2-74
First edition
2017-05
Medical electrical equipment —
Part 2-74:
Particular requirements for basic
safety and essential performance of
respiratory humidifying equipment
Appareils électromédicaux —
Partie 2-74: Exigences particulières pour la sécurité de base et
les performances essentielles des équipements d’humidification
respiratoire
Reference number
©
ISO 2017
© ISO 2017, Published in Switzerland
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ii © ISO 2017 – All rights reserved

Contents Page
Foreword . v
Introduction . vii
201.1   Scope, object and related standards . 1
201.2   Normative references . 3
201.3   Terms and definitions . 5
201.4   General requirements . 7
201.5   General requirements for testing of ME EQUIPMENT . 10
201.6   Classification of ME EQUIPMENT and ME SYSTEMS . 11
201.7   ME EQUIPMENT identification, marking and documents . 11
201.8   Protection against electrical HAZARDS form ME EQUIPMENT . 19
201.9   Protection against mechanical hazards of ME EQUIPMENT and ME SYSTEMS . 19
201.10   Protection against unwanted and excessive radiation HAZARDS . 21
201.11   Protection against excessive temperatures and other HAZARDS . 21
201.12   Accuracy of controls and instruments and protection against
hazardous outputs . 24
201.13   HAZARDOUS SITUATIONS and fault conditions for ME EQUIPMENT . 27
201.14   Programmable electrical medical systems (pems) . 28
201.15   Construction of ME EQUIPMENT . 28
201.16   ME SYSTEMS . 29
201.17   Electromagnetic compatibility of ME EQUIPMENT and ME SYSTEMS . 29
201.101   BREATHING SYSTEM connectors and ports . 29
201.102   Requirements for the BREATHING SYSTEM and ACCESSORIES . 32
201.103   LIQUID CONTAINER . 33
201.104   FUNCTIONAL CONNECTION . 34
202   Electromagnetic disturbances — Requirements and tests . 34
206   Usability . 35
208   General requirements, tests and guidance for alarm systems in medical
electrical equipment and medical electrical systems . 36
211   Requirements for medical electrical equipment and medical electrical
systems used in the home healthcare environment . 36
Annex C (informative)  Guide to marking and labelling requirements for
ME EQUIPMENT and ME SYSTEMS . 38
Annex D (informative)  Symbols on Marking . 44
Annex AA (informative)  Particular guidance and rationale . 45
Annex BB (normative)  * Determination of the accuracy of the displayed MEASURED
GAS TEMPERATURE . 61
Annex CC (normative)  * Determination of the HUMIDIFICATION OUTPUT . 63
Annex DD (normative)  * Specific enthalpy calculations . 67
© ISO 2017 – All rights reserved iii

Annex EE (normative)  Removable temperature sensors and mating ports . 69
Annex FF (normative)  * Standard temperature sensor . 73
Annex GG (informative)  Saturation vapour pressure . 76
Annex HH (informative)  Reference to the essential principles of safety and
[7]
performance of medical devices in accordance with ISO 16142-1:2016 . 77
Annex II (informative)  Terminology — Alphabetized index of defined terms . 81
Bibliography . 85

iv © ISO/IEC 2016 – All rights reserved

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).
Attention is drawn to the possibility that some of the elements of this document may be the
subject of patent rights. ISO shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in
the Introduction and/or on the ISO list of patent declarations received (see
www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and
does not constitute an endorsement.
For an explanation on 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 the following URL:
www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 121, Anaesthetic and respiratory
equipment, Subcommittee SC 3, Lung ventilators and related equipment and IEC/TC 62, Electrical
equipment in medical practice, Subcommittee SC 62D, Electromedical equipment.
[1]
This first edition of ISO 80601‐2‐74 cancels and replaces the third edition of ISO 8185:2007 ,
which has been technically revised. It also incorporates the third edition of IEC 60601‐1,
including amendment 1, the fourth edition of IEC 60601‐1‐2, the third edition of IEC 60601‐1‐6,
including amendment 1, the second edition of IEC 60601‐1‐8, including amendment 1, and the
second edition of IEC 60601‐1‐11.
The most significant changes are the following modifications:
— extending the scope to include the HUMIDIFIER and its ACCESSORIES, where the characteristics
of those ACCESSORIES can affect the BASIC SAFETY and ESSENTIAL PERFORMANCE of the HUMIDIFIER,
and thus not only the HUMIDIFIER itself;
— identification of ESSENTIAL PERFORMANCE for a HUMIDIFIER and its ACCESSORIES;
— modification of the humidification test PROCEDURE and the disclosure of humidification
performance;
© ISO 2017 – All rights reserved v

— more fully dimensioning the removable temperature sensor port and sensor;
— removal of requirements for so‐called “bubble” HUMIDIFIERS as a separate document is being
[8]
prepared for them ;
and the following additions:
— requirements for mechanical strength (via IEC 60601‐1‐11);
— new symbols;
— requirements for a HUMIDIFIER as a component of an ME SYSTEM;
— requirements for ENCLOSURE integrity (water ingress via IEC 60601‐1‐11);
— requirements for cleaning and disinfection PROCEDURES (via IEC 60601‐1‐11);
— requirements for BIOCOMPATIBILITY;
— requirements for USABILITY.
vi © ISO 2017 – All rights reserved

Introduction
This document specifies requirements for respiratory humidifying equipment intended for use
on PATIENTS in HOME HEALTHCARE ENVIRONMENT and in healthcare facilities. HUMIDIFIERS are used to
raise the water content of gases delivered to PATIENTS. Gases available for medical use do not
contain sufficient moisture and can damage or irritate the respiratory tract or desiccate
secretions of PATIENTS whose upper airways have been bypassed. Inadequate humidity at the
PATIENT‐CONNECTION PORT can cause drying of the upper airway, or desiccation of tracheo‐
bronchial secretions in the tracheal or tracheostomy tube, which can cause narrowing or even
[19][20]
obstruction of the airway . Heat is employed to increase the water output of the HUMIDIFIER.
In addition, many HUMIDIFIERS utilize heated BREATHING TUBES in order to increase operating
efficiency and reduce water loss (condensate) as well as heat loss in the BREATHING TUBE.
Ventilator and anaesthesia BREATHING TUBES in common use might not withstand the heat
generated by HUMIDIFIERS and BREATHING TUBE heating mechanisms.
Many HUMIDIFIER MANUFACTURERS use off‐the‐shelf electrical connectors for their electrically
heated BREATHING TUBES. However, since different MANUFACTURERS have used the same electrical
connector for different power 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 burns and fires. It was not found practical to
specify the interface requirements for electrical connectors to ensure compatibility between
HUMIDIFIERS and BREATHING TUBES produced by different MANUFACTURERS.
Since the safe use of a HUMIDIFIER depends on the interaction of the HUMIDIFIER with its many
ACCESSORIES, this document sets total system performance requirements up to the PATIENT‐
CONNECTION PORT. These requirements are applicable to ACCESSORIES such as BREATHING TUBES
(both heated and non‐heated), temperature sensors and equipment intended to control the
environment within these BREATHING TUBES.
Humidification can also be used by respiratory support ME EQUIPMENT to increase PATIENT
comfort and compliance with the therapy. Examples are obstructive sleep apnoea and nasal high
flow therapy equipment. The HUMIDIFICATION OUTPUT requirements of such ME EQUIPMENT is less
demanding as the PATIENT’S upper airway is not bypassed.
HUMIDIFIERS are commonly used with air and air‐oxygen mixtures and any HUMIDIFIER should be
able to operate with these gases. Care should be taken if using other gas mixes such as helium‐
oxygen mixtures, as the different physical and thermal properties of these gases may disturb the
operation of the HUMIDIFIER.
In this document, the following print types are used:
— Requirements and definitions: roman type;
— Test specifications: italic type;
— Informative material appearing outside of tables, such as notes, examples and references: in
smaller type. Normative text of tables is also in a smaller type;
— Terms defined in CLAUSE 3 of the general standard, in this document or as noted: small
capitals;
© ISO 2017 – All rights reserved vii

In referring to the structure of this document, the term
— “clause” means one of the five numbered divisions within the table of contents, inclusive of
all subdivisions (e.g. Clause 201 includes subclauses 201.7, 201.8, etc.);
— “subclause” means a numbered subdivision of a clause (e.g. 201.7, 201.8 and 201.9 are all
subclauses of Clause 201).
References to clauses within this document are preceded by the term “Clause” followed by the
clause number. References to subclauses within this document are by number only.
In this document, the conjunctive “or” is used as an “inclusive or” so a statement is true if any
combination of the conditions is true.
The verbal forms used in this document conform to usage described in Annex H of the ISO/IEC
Directives, Part 2. For the purposes of this document, the auxiliary verb:
— “shall” means that compliance with a requirement or a test is mandatory for c
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