UNE-EN ISO 20789:2020

This document specifies requirements for so-called cold bubble-through or cold pass-over humidifying equipment, hereafter referred to as a passive humidifier. Figure 1 and Figure 2 illustrate these passive humidifiers.

NOTE 1 Passive humidifier humidification chambers are at room temperature so they have a lower humidification output than active humidifiers.

Figure 1 Cold pass-over passive humidifier

Figure 2 Cold bubble-through passive humidifier

This document is also applicable to those accessories intended by their manufacturer to be connected to a passive humidifier.

A passive humidifier integrated into another medical device is subject to the requirements of the standard of the other medical device.

EXAMPLE 1 The requirements in ISO 80601-2-69[4] also apply to a passive humidifier integrated into an oxygen concentrator.

EXAMPLE 2 The requirements in ISO 80601-2-70[5] also apply a passive humidifier integrated into sleep apnoea therapy equipment.



This document does not specify the requirements for active heated humidifiers, heated breathing tubes, or active heat and moisture exchangers (HMEs), the requirements for which are given in ISO 80601-2-74.

NOTE 2 ISO 5367 specifies other safety and performance requirements for breathing tubes.

This document is not applicable to a passive HME, which returns a portion of the expired moisture and heat of the patient to the respiratory tract during inspiration without adding heat or moisture, the requirements for which are given in ISO 9360-1[6] and ISO 9360-2[7].

This document is not applicable to nebulizers used for the delivery of liquids to patients, the requirements for which are given in ISO 27427[8].

This document is not applicable to equipment commonly referred to as room humidifiers or humidifiers used in heating, ventilation and air conditioning systems, or humidifiers incorporated into infant incubators.

An asterisk (*) as the first character of a title or at the beginning of a paragraph or table title indicates that there is guidance or rationale related to that item in Annex A.

This document has been prepared to support the essential principles of safety and performance of a passive humidifier and related accessories as medical devices in accordance with ISO 16142-1:2016. Annex D maps the clauses and subclauses of this document with the essential principles of ISO 16142-1:2016.