SIST EN ISO 12487:2026

SLOVENSKI STANDARD
01-september-2026
Medicinska električna oprema - Klinično vrednotenje učinkovitosti kliničnih
termometrov (ISO 12487:2026)
Medical electrical equipment - Clinical performance evaluation of clinical thermometers
(ISO 12487:2026)
Medizinische elektrische Geräte - Prüfung der klinischen Leistung von medizinischen
Thermometern (ISO 12487:2026)
Équipement respiratoire - Investigation clinique des thermomètres cliniques (ISO
12487:2026)
Ta slovenski standard je istoveten z: EN ISO 12487:2026
ICS:
11.040.55 Diagnostična oprema Diagnostic equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 12487
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2026
EUROPÄISCHE NORM
ICS 11.040.55
English Version
Medical electrical equipment - Clinical performance
evaluation of clinical thermometers (ISO 12487:2026)
Appareils électromédicaux - Évaluation de la Medizinische elektrische Geräte - Prüfung der
performance clinique des thermomètres médicaux (ISO klinischen Leistung von medizinischen Thermometern
12487:2026) (ISO 12487:2026)
This European Standard was approved by CEN on 30 May 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 12487:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 12487:2026) has been prepared by Technical Committee ISO/TC 121
"Anaesthetic and respiratory equipment" in collaboration with Technical Committee CEN/TC 205 “Non-
active 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 December 2026, and conflicting national standards
shall be withdrawn at the latest by December 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 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.
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 12487:2026 has been approved by CEN as EN ISO 12487:2026 without any modification.

International
Standard
ISO 12487
First edition
Medical electrical equipment —
2026-05
Clinical performance evaluation of
clinical thermometers
Appareils électromédicaux — Évaluation de la performance
clinique des thermomètres médicaux
Reference number
ISO 12487:2026(en) © ISO 2026
ISO 12487:2026(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
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 12487:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General requirements . 7
4.1 Clinical investigation methods .7
4.2 Good clinical practice .8
4.3 Status of previous clinical investigations .8
4.4 Disclosure of summary of clinical investigation .8
5 Clinical investigation . 8
5.1 Subject requirements.8
5.1.1 Number .8
5.1.2 Age distribution .8
5.1.3 Body temperature distribution .9
5.1.4 Body site for clinical investigation .9
5.1.5 Exception criteria .10
5.2 Clinical investigation method with a reference thermometer .10
5.2.1 Environmental condition of clinical investigation .10
5.2.2 Subject preparation for body temperature stabilization .10
5.2.3 Reference thermometer measurement .11
5.2.4 Clinical thermometer-under-test .11
5.3 Procedure .11
5.3.1 Clinical thermometers with time prediction . 12
5.3.2 Clinical thermometers with site conversion . 12
6 Data analysis .13
6.1 Correction of the readings of the reference thermometer . 13
6.2 Clinical bias calculation . 13
6.3 Standard deviation of the clinical bias calculation.14
6.4 Clinical repeatability calculation .14
7 Acceptance criteria . 14
7.1 Clinical bias . .14
7.2 Standard deviation of the clinical bias . 15
7.3 Clinical repeatability . 15
Annex A (informative) Particular guidance and rationale .16
Annex B (informative) Guide to disclosure requirements .22
Annex C (informative) Terminology — alphabetized index of defined terms .23
Bibliography .25

iii
ISO 12487:2026(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 121, Anaesthetic and respiratory equipment,
Subcommittee SC 3, Respiratory devices and related equipment used for patient care, and Technical Committee
IEC/TC 62, Medical equipment, software, and systems, Subcommittee SC 62D, Particular medical equipment,
software, and systems, in collaboration with the European Committee for Standardization (CEN) Technical
Committee CEN/TC 205, Non-active medical devices, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
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 12487:2026(en)
Introduction
Determining body temperature is an important procedure that is clinically used to assess the status of
patients as well as blood pressure, SpO and pulse rate. This document is intended to provide the necessary
requirements for the clinical investigation to ensure that the essential performance of these clinical
thermometer is at an adequate level.
In this document, the following print types are used.
— Requirements and definitions: roman type.
— Terms defined in Clause 3 of this document or as noted: 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.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “may” indicates a permission;
— “can” is used to describe a possibility or capability; and
— “must” is used to indicate an external constraint.

v
International Standard ISO 12487:2026(en)
Medical electrical equipment — Clinical performance
evaluation of clinical thermometers
1 Scope
This document specifies the requirements and methods for the clinical investigation of medical electrical
(ME) equipment used to measure the body temperature in indirect measurement mode.
This document covers both intermittently and continuously measuring clinical thermometers.
NOTE 1 This document does not apply to clinical thermometers measuring the body temperature in direct
measurement mode.
NOTE 2 For clinical thermometers in direct measurement mode determining the technical accuracy in accordance
1)
with ISO 80601-2-56:— is considered sufficient.
This document is applicable to clinical thermometers with claimed measurement time shorter than
60 seconds (for methods such as oral or rectal measurement), or shorter than 5 minutes (for methods such
as axillary measurement), and which are treated as predictive type thermometers and fall under the scope of
this document.
This document specifies additional disclosure requirements.
This document does not apply to the clinical investigation of a screening thermographs for human febrile
temperature screening whose laboratory accuracy requirements are described in IEC 80601-2-59.
This document does not apply to pulmonary artery catheter for the determination of cardiac output by
thermodilution.
1)
NOTE 3 ISO 80601-2-56:— does include pulmonary artery catheter for the determination of cardiac output by
thermodilution.
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 14155:2026, Clinical investigation of medical devices for human subjects — Good clinical practice
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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/
NOTE An alphabetized index of defined terms is found in Annex C.
1) Third edition under preparation. Stage at the time of balloting: ISO/DIS 80601-2-56.

ISO 12487:2026(en)
3.1
accompanying information
information supplied by the manufacturer (3.16) with or marked on a medical device or accessory for the
user or responsible organization, particularly regarding safe use
Note 1 to entry: The accompanying information is regarded as part of the medical device or accessory.
Note 2 to entry: The accompanying information can consist of the label, marking, instructions for use (3.14), technical
description, installation manual, quick reference guide, etc. and can address the installation, use, processing,
maintenance and disposal of the medical device or accessory.
Note 3 to entry: Accompanying information is not necessarily a written or printed document but can involve auditory,
visual, or tactile materials and multiple media types (e.g. CD-ROM, DVD-ROM, USB stick, website).
[SOURCE: ISO 20417:2026, 3.2, modified — Notes 4 and 5 to entry and the figure have been deleted.]
3.2
application site
measuring site
body location of a patient (3.19) that the probe (3.20) directly interacts with
EXAMPLE Ear canal, oral (sublingual pocket), axilla (armpit), rectum, centre of forehead, temple, inner canthus,
temporal artery, bladder.
Note 1 to entry: Measurement at the application site is either contact or non-contact (e.g. infrared).
[SOURCE: ISO 80601-2-56:—, 201.3.220, modified —“application site” has been added as a preferred term,
the Example was changed and Note 1 to entry was added.]
3.3
clinical accuracy
closeness of agreement between the output temperature (3.18) of a clinical thermometer (3.8) and the
reference value of the temperature of the reference site (3.25) that the clinical thermometer purports to
represent
[SOURCE: ISO 80601-2-56:—, 201.3.205]
3.4
clinical bias
Δ
cb
mean difference between output temperatures (3.18) of a clinical thermometer (3.8) and a reference
thermometer (3.26) for the intended reference site (3.25)
Note 1 to entry: The application site (3.2) can be the same as or different from the reference site.
3.5
clinical investigation
clinical trial
clinical study
systematic investigation in one or more human subjects, undertaken to assess the clinical performance,
effectiveness or safety of a medical device
[SOURCE: ISO 14155:2026, 3.9]
3.6
clinical investigation report
clinical study report
document describing the design, conduct, statistical analysis and results of a clinical investigation (3.5)
[SOURCE: ISO 14155:2026, 3.11]

ISO 12487:2026(en)
3.7
clinical repeatability
σ
repeat
pooled standard deviation (over a selected group of subjects) of changes in multiple output temperatures
(3.18) taken from the same subject at the same application site (3.2) with the same clinical thermometer (3.8)
by the same operator within a relatively short time
[SOURCE: ASTM E1965-98, 3.2.10, modified — focus changed from “ear canal temperature” to the more
general “application site” and the parenthetical part “(over a selected group of subjects)” was included.]
3.8
clinical thermometer
medical electrical (ME) equipment (3.17) used for measuring at the application site (3.2) and indicating the
temperature at the reference site (3.25)
Note 1 to entry: The application site can be the same as the reference site.
[SOURCE: ISO 80601-2-56:—, 201.3.206, modified — “measuring site” has been replaced with “application
site”.]
3.9
clinical thermometer-under-test
DUT
clinical thermometer (3.8) undergoing clinical investigation (3.5)
3.10
direct measurement mode
operating mode of a clinical thermometer (3.8) where the output temperature (3.18) represents the
temperature of the application site (3.2) with which the probe (3.20) is in thermal equilibrium (3.31)
[SOURCE: ISO 80601-2-56:—, 201.3.207, modified — “measuring site” has been replaced with “application
site”.]
3.11
essential performance
performance of a clinical function, other than that related to basic safety, where loss or degradation beyond
the limits specified by the manufacturer (3.16) results in an unacceptable risk (3.27)
Note 1 to entry: Essential performance is most easily understood by considering whether its absence or degradation
would result in an unacceptable risk.
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.27]
3.12
indicated site
indicated body site
body site to which the output temperature (3.18) of the clinical thermometer (3.8) refers
EXAMPLE 1 Ear canal, oral (sublingual pocket), axilla, rectum, core body.
Note 1 to entry: The indicated site may differ from the application site (3.2).
EXAMPLE 2 Site conversion (3.29) clinical thermometers.
Note 2 to entry: There is guidance or rationale for this definition contained in A.2.1.

ISO 12487:2026(en)
3.13
indirect measurement mode
operating mode of a clinical thermometer (3.8) where the output temperature (3.18) represents the
temperature of an application site (3.2) with which the probe (3.20) is not in thermal equilibrium (3.31) or
where the application site is not the indicated site (3.12)
Note 1 to entry: Infrared clinical thermometers are not typically in thermal equilibrium with the application site and are
therefore typically in indirect measurement mode.
Note 2 to entry: Clinical thermometers with claimed measurement time shorter than 60 seconds (for methods such as
oral or rectal measurement), or shorter than 5 minutes (for methods such as axillary measurement) are considered in
indirect measurement mode.
[SOURCE: ISO 80601-2-56:—, 201.3.214, modified — “measuring site” has been replaced with “application
site”; “or where the application site is not the indicated site” was added to the definition; Note 2 to entry was
added.]
3.14
instructions for use
IFU
package insert
portion of the accompanying information (3.1) that is
— directed to the user, and
— essential for the safe and effective use of a medical device or accessory
[SOURCE: ISO 20417:2026, 3.16, modified — Notes to entry have been deleted.]
3.15
laboratory accuracy
closeness of agreement between the output temperature (3.18) of a clinical thermometer (3.8) and a reference
thermometer (3.26) when measuring a reference temperature source (e.g. water bath or black body) under
laboratory conditions
Note 1 to entry: Laboratory accuracy is sometimes referred to as maximum permissible error.
[SOURCE: ISO 80601-2-56:—, 201.3.217, modified — added to the definition “when measuring a reference
temperature source (e.g. water bath or black body) under laboratory conditions”.]
3.16
manufacturer
natural or legal person with responsibility for the design, manufacture, packaging, or labelling of medical
electrical (ME) equipment (3.17), assembling an ME system, or adapting ME equipment or an ME system,
regardless of whether these operations are performed by that person or on his behalf by (an)other person(s)
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.55, modified — Notes to entry have been deleted.]
3.17
medical electrical equipment
ME equipment
electrical equipment having an applied part or transferring energy to or from the patient (3.19) or detecting
such energy transfer to or from the patient and which is:
a) provided with not more than one connection to a particular supply mains; and
b) intended by its manufacturer (3.16) to be used:
1) in the diagnosis, treatment, or monitoring of a patient; or
2) for compensation or alleviation of disease, injury or disability

ISO 12487:2026(en)
Note 1 to entry: ME equipment includes those accessories as defined by the manufacturer that are necessary to enable
the normal use of the ME equipment.
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.63, modified — Notes 2 to 5 to entry have been
deleted.]
3.18
output temperature
temperature indicated by a clinical thermometer (3.8)
Note 1 to entry: Methods of indication can include printed, spoken, displayed and remotely displayed.
[SOURCE: ISO 80601-2-56:—, 201.3.223, modified — replaced “thermometer” with “clinical thermometer”.]
3.19
patient
living being (person or animal) undergoing a medical, surgical or dental procedure (3.22)
Note 1 to entry: A patient can be an operator.
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.76]
3.20
probe
part of a clinical thermometer (3.8) that provides a thermal coupling between the sensor (3.28) and the
patient (3.19)
Note 1 to entry: Thermal coupling can be contact or non-contact.
[SOURCE: ISO 80601-2-56:—, 201.3.225]
3.21
probe cover
disposable or reusable accessory of a clinical thermometer (3.8) that provides a sanitary barrier between the
probe (3.20) and the patient (3.19)
[SOURCE: ISO 80601-2-56:—, 201.3.227]
3.22
procedure
specified way to carry out an activity or a process (3.23)
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.88]
3.23
process
set of interrelated or interacting activities that use inputs to deliver an intended result
Note 1 to entry: Whether the “intended result” of a process is called output, product or service depends on the context
of the reference.
Note 2 to entry: Inputs to a process are generally the outputs of other processes and outputs of a process are generally
the inputs to other processes.
Note 3 to entry: Two or more interrelated and interacting processes in series can also be referred to as a process.
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.89]
3.24
rated
term referring to a value assigned by the manufacturer (3.16) for a specified operating condition
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.97]

ISO 12487:2026(en)
3.25
reference site
reference body site
body site where the reference thermometer (3.26) measures temperature as the reference value for clinical
investigation (3.5)
EXAMPLE Ear canal, oral (sublingual pocket), axilla, rectum, bladder.
3.26
reference thermometer
thermometer with a specified accuracy and associated uncertainty, whose calibration is traceable to
a national standard of temperature, measuring in equilibrium either at the reference site (3.25) in direct
measurement mode (3.10) or for laboratory application
3.27
risk
combination of the probability of occurrence of harm and the severity of that harm
[SOURCE: ISO 14971:2019, 3.18]
3.28
sensor
part of the clinical thermometer (3.8) that converts thermal energy into an electrical signal
[SOURCE: ISO 80601-2-56:—, 201.3.231]
3.29
site conversion
process (3.23) of measuring temperature at a measurement site and converting the value to another site
[SOURCE: ISO 80601-2-56:—, 201.3.232]
3.30
test mode
state of a clinical thermometer (3.8) where the output temperature (3.18) represents the temperature
measured by the sensor (3.28) and does not include site conversion (3.29) or time prediction (3.32)
Note 1 to entry: The test mode is used for the determination of the laboratory accuracy (3.15) of the clinical thermometer.
Note 2 to entry: The test mode does not necessarily need to be an additional mode and may be the direct measurement
mode (3.10) of the clinical thermometer.
[SOURCE: ISO 80601-2-56:—, 201.3.239]
3.31
thermal equilibrium
measurement status after which the further output temperature (3.18) change is < 0,1 °C/16 seconds
Note 1 to entry: For methods such as oral or rectal measurement.
3.32
time prediction
process (3.23) of predicting the temperature of an application site (3.2) before thermal equilibrium (3.31) has
been reached
[SOURCE: ISO 80601-2-56:—, 201.3.240, modified — “measurement site” has been replaced with “application
site”.]
ISO 12487:2026(en)
3.33
type test
test on a representative sample of the equipment with the objective of determining if the equipment, as
designed and manufactured, can meet the requirements of this document
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.135]
3.34
verification
confirmation through the provision of objective evidence that specified requirements have been fulfilled
Note 1 to entry: The objective evidence needed for a verification can be the result of an inspection or of other forms of
determination such as performing alternative calculations or reviewing documents.
Note 2 to entry: The activities carried out for verification are sometimes called a qualification process.
Note 3 to entry: The term “verified” is used to designate the corresponding status.
[SOURCE: IEC 60601-1:2005+AMD1: 2012+ AMD2: 2020, 3.138]
4 General requirements
NOTE There is guidance or rationale for this Clause contained in A.2.2.
4.1 Clinical investigation methods
The following basic principles shall apply to the clinical investigation methods according to this document.
a) Clinical thermometers in indirect measurement mode shall undergo clinical investigation according to this
document.
b) The clinical investigation shall be considered a type test.
NOTE The representative sample used for this type test can consist of one or multiple clinical thermometers.
c) Unless otherwise specified in this document, the manufacturer shall consider:
1) the sequential method when the physical interference between the probes of the clinical thermometer
and the reference thermometer is concerned;
2) the simultaneous method when the temperature variation between measurements is concerned.
d) The clinical investigation should include a wide variety of representative cases in the test conditions for
testing clinical thermometers, which are markedly dependent on:
1) ambient temperature;
EXAMPLE 1 Cases representing near the lower and higher ends of the operating temperature range in the
accompanying information.
2) distance between the clinical thermometer and the measurement site; or
EXAMPLE 2 Cases representing near the shorter and longer ends of the measurement distance range in
the accompanying information.
3) body temperature.
EXAMPLE 3 Cases representing near the lower and higher ends of the body temperature range in the
accompanying information.
Check conformity by inspection of the clinical investigation report.

ISO 12487:2026(en)
4.2 Good clinical practice
The following basic principles shall apply to the clinical investigation according to this document.
a) All clinical investigations shall comply with the requirements of ISO 14155:2026.
b) Clinical investigation with invasive reference site with skin puncture or invasive application site with
skin puncture should not be used for patients or subjects solely for the purpose of investigating clinical
thermometer performance.
NOTE Some authorities having jurisdiction have additional requirements.
c) The requirements of this document, which are more specific than the corresponding requirements of
ISO 14155:2026, shall prevail.
Check conformity by application of the requirements of ISO 14155:2026.
4.3 Status of previous clinical investigations
The clinical investigation results for clinical thermometers that have been successfully clinically investigated
according to previous editions of ISO 80601-2-56:
a) remain valid; and
b) a clinical investigation need not be repeated to conform with this document.
4.4 Disclosure of summary of clinical investigation
The accompanying information shall contain a statement that a clinical investigation according to this
document was successfully performed.
Check conformity by inspection of the accompanying information.
NOTE Annex B contains a guide to assist the readers in disclosure contained in other clauses of this document.
5 Clinical investigation
NOTE There is guidance or rationale for this Clause contained in A.2.4.
5.1 Subject requirements
NOTE There is guidance or rationale for this subclause contained in A.2.5.
5.1.1 Number
The following basic principles shall apply to the number of the subjects.
a) The minimum number of subjects in the verification of clinical accuracy shall be not less than 75.
b) If a clinical thermometer has multiple modes, all modes shall be verified separately with a minimum
number of 75 subjects per mode.
Check conformity by inspection of the clinical investigation report.
5.1.2 Age distribution
The following basic principles shall apply to the age distribution of the subjects.
a) The verification of clinical accuracy shall be carried out on intended age groups indicated in the
accompanying information.
ISO 12487:2026(en)
b) For basal (ovulation) clinical thermometers no age distribution is necessary.
c) The minimum number of subjects in an age group shall be at least 25.
d) Table 1 lists relevant age groups.
Table 1 — Relevant age groups
Age group
less than 3 months
3 months to less than 18 months
18 months and older
e) The age distribution shall be disclosed in the clinical investigation report.
Check conformity by inspection of the clinical investigation report.
5.1.3 Body temperature distribution
NOTE There is guidance or rationale for this subclause contained in A.2.6.
The following basic principles shall apply to the body temperature distribution of the subjects.
a) At least 30 % of all subjects shall have a reference temperature of below 37,5 °C.
b) At least 30 % of all subjects shall have a reference temperature of above 37,5 °C.
c) The body temperature distribution shall be disclosed in the clinical investigation report.
Check conformity by inspection of the clinical investigation report.
5.1.4 Body site for clinical investigation
NOTE There is guidance or rationale for this subclause contained in A.2.7.
The following basic principles shall apply to the body site for clinical investigation.
a) The same site as the indicated site shall be used for the reference site, in principle.
b) In case a different site from the indicated site is used for the reference site, the manufacturer shall justify
the reason and the impact on the accuracy of the clinical investigation.
EXAMPLE Physiological restrictions (e.g. nasal obstruction or children with involuntary mouth breathing),
or ethical restrictions (e.g. rectal measurement in certain age groups).
c) The measurement site and indicated site shall be disclosed in the accompanying information and clinical
investigation report.
d) If the reference site differs from the indicated site, the reference site shall be disclosed in the accompanying
information and clinical investigation report.
e) If the instructions for use indicate that the clinical thermometer-under-test has multiple modes
representing different indicated sites, a separate clinical investigation shall be performed for each
indicated site.
Check conformity by inspection of the accompanying information and clinical investigation report.

ISO 12487:2026(en)
5.1.5 Exception criteria
This document recognizes and appreciates the difficulty in collecting clinical data when requiring subjects
with transient and potentially serious health conditions such as elevated body temperature. The following
subgroups are not required in the clinical test sample population:
— subjects under 3 months of age with elevated temperature.
5.2 Clinical investigation method with a reference thermometer
5.2.1 Environmental condition of clinical investigation
The ambient temperature and humidity during the clinical investigation shall be:
a) recorded;
b) within the rated temperature and humidity as indicated in the accompanying information of the clinical
thermometer-under-test;
c) disclosed in the clinical investigation report.
Check conformity by inspection of the accompanying information and the clinical investigation report.
5.2.2 Subject preparation for body temperature stabilization
The following basic principles shall apply to the subject preparation of the clinical investigation.
a) Unless otherwise indicated in the instructions for use of the clinical thermometer-under-test, the following
shall apply to the subject at least 15 min prior to and throughout the clinical investigation to stabilize
body temperature:
1) be exposed to the environmental condition of the verification of clinical accuracy;
2) keep as still as possible for the stable body temperature;
3) do not change any clothes;
4) sit or lie naturally while being relaxed without warming up or cooling down the application site
unnaturally;
5) keep axilla closed for axillary measurements.
b) The following may apply at least 15 min prior to and throughout the clinical investigation, if the
manufacturer excludes the related conditions of use in the instructions for use to stabilize body
temperature:
1) be out of direct sun, near heat, cooling or air circulation sources;
2) do not eat or drink anything;
3) keep the application site dry by wiping the sweat off, if applicable;
4) remove ear wax, if applicable; and
5) remove cosmetics of the application site, if applicable.
c) Unless otherwise intended, the subject may be excluded, if one of the following applies:
1) inflammation on the application site;
2) has taken antipyretics in the preceding 120 min;
3) any other medical conditions which can skew the results of the verification of clinical accuracy.

ISO 12487:2026(en)
Check conformity by inspection of the clinical investigation report.
5.2.3 Reference thermometer measurement
5.2.3.1 Reference site
The following basic principles shall apply to the reference site of the clinical investigation.
NOTE Additional requirements about the reference site are found in 5.1.4.
a) The reference site shall be the same in all subjects of the clinical investigation, in principle.
b) In case the reference site is not the same in all subjects of the clinical investigation, the manufacturer shall
justify the reason and the impact on the accuracy of the clinical investigation.
EXAMPLE Physiological restrictions (e.g. nasal obstruction or children with involuntary mouth breathing),
or ethical restrictions (e.g. rectal measurement in certain age groups).
c) In case the reference site is not the same in all subjects of the clinical investigation, the manufacturer shall
disclose this fact in the accompanying information and the clinical investigation report.
Check conformity by inspection of the clinical investigation report and the accompanying information.
5.2.3.2 Reference thermometer
NOTE There is guidance or rationale for this subclause contained in A.2.8.
The following basic principles shall apply to the reference thermometer.
a) The reference thermometer shall have a corrected laboratory accuracy of at least ±0,1 °C and shall be
used in accordance with its instructions for use.
b) Reference thermometers shall be direct measurement mode thermometers.
Non-electronic thermometers may be used.
c) For the clinical investigation of a clinical thermometer with time prediction, a direct measurement mode or
test mode of the DUT may be used as the reference thermometer after achieving thermal equilibrium.
Check conformity by inspection of the clinical investigation report.
5.2.4 Clinical thermometer-under-test
The following basic principles shall apply to the clinical thermometer-under-test.
a) A clinical thermometer intended for use with a probe cover shall be tested together with the probe cover
as indicated in the accompanying information.
b) A new probe cover shall be used for each subject.
Check conformity by inspection of the clinical investigation report.
5.3 Procedure
NOTE 1 There is guidance or rationale for this subclause contained in A.2.9.
NOTE 2 There are some cases where the procedure is not applicable.
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