prEN ISO 9680

SLOVENSKI STANDARD
01-junij-2025
Nadomešča:
SIST EN ISO 9680:2022
Zobozdravstvo - Operacijska razsvetljava (ISO/DIS 9680:2025)
Dentistry - Operating lights (ISO/DIS 9680:2025)
Zahnheilkunde - Behandlungsleuchten (ISO/DIS 9680:2025)
Médecine bucco-dentaire - Luminaires opératoires (ISO/DIS 9680:2025)
Ta slovenski standard je istoveten z: prEN ISO 9680
ICS:
11.060.20 Zobotehnična oprema Dental equipment
91.160.10 Notranja razsvetljava Interior lighting
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 9680
ISO/TC 106/SC 6
Dentistry — Operating lights
Secretariat: DIN
Médecine bucco-dentaire — Luminaires opératoires
Voting begins on:
2025-03-31
ICS: 11.060.20
Voting terminates on:
2025-06-23
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 is circulated as received from the committee secretariat.
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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 9680:2025(en)
DRAFT
ISO/DIS 9680:2025(en)
International
Standard
ISO/DIS 9680
ISO/TC 106/SC 6
Dentistry — Operating lights
Secretariat: DIN
Médecine bucco-dentaire — Luminaires opératoires
Voting begins on:
ICS: 11.060.20
Voting terminates on:
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 is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2025
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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TO SUBMIT, WITH THEIR COMMENTS,
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NOTIFICATION OF ANY RELEVANT PATENT
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RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
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Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 9680:2025(en)
ii
ISO/DIS 9680:2025(en)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 2
4.1 Optical requirements .2
4.1.1 Adjustable level of illuminance .2
4.1.2 Illumination pattern.2
4.1.3 Illuminance in patient's eyes .4
4.1.4 Chromatic uniformity .4
4.1.5 Chromaticity and correlated colour temperature .5
4.1.6 Shadow .5
4.1.7 Colour fidelity.6
4.1.8 Actinic UV hazard exposure for the skin and eye .6
4.1.9 Near-UV hazard exposure for the eye .6
4.1.10 Retinal blue light hazard exposure .6
4.1.11 Single fault condition for photobiological safety .6
4.1.12 Heat due to optical radiation .7
4.1.13 Compatibility with light-activated restorative materials.7
4.2 Mechanical requirements .7
4.2.1 Operating controls .7
4.2.2 Stability after positioning .7
4.2.3 Expelled parts .7
4.3 Reprocessing .7
4.4 Electrical requirements.8
4.5 Usability .8
5 Sampling . 8
6 Testing. 8
6.1 General .8
6.2 Visual inspection .8
6.3 Optical tests .8
6.3.1 Test set-up .8
6.3.2 Level of illuminance and illuminance pattern .9
6.3.3 Illuminance uniformity .9
6.3.4 Illuminance in the patient’s eyes .9
6.3.5 Chromatic uniformity .9
6.3.6 Chromaticity and correlated colour temperature .10
6.3.7 Shadow .10
6.3.8 Colour fidelity.11
6.3.9 Actinic UV hazard exposure for the skin and eye .11
6.3.10 Near-UV hazard exposure for the eye . 12
6.3.11 Retinal blue light hazard exposure . 12
6.3.12 Heat due to optical radiation .14
6.3.13 Compatibility with light-activated restorative materials.14
7 Manufacturer's instructions . 14
7.1 Documents.14
7.2 Instructions for use .14
7.3 Technical description. 15
7.4 Check . 15
8 Packaging.15
8.1 General . 15

iii
ISO/DIS 9680:2025(en)
8.2 Identification . 15
9 Marking . .16
9.1 Marking on the outside of operating lights .16
9.2 Graphical symbols .16
Annex A (informative) Additional information for retinal blue light hazard exposure test
method . 17
Annex B (normative) Normalized absorbance of camphorquinone .21
Bibliography .24

iv
ISO/DIS 9680:2025(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.
This document was prepared by Technical Committee ISO/TC 106, Dentistry, Subcommittee SC 6, Dental
equipment, in collaboration with the European Committee for Standardization (CEN) Technical Committee
CEN/TC 55, Dentistry, in accordance with the Agreement on technical cooperation between ISO and CEN
(Vienna Agreement).
This fifth edition cancels and replaces the fourth edition (ISO 9680:2021), which has been technically
revised.
The main changes are as follows:
— Clause 4 “Classification” has been deleted and the following Clauses have been re-numbered;
— Clause 5 “Requirements and Recommendations” was adapted to Clause 4 “Requirements” and technically
updated;
— Clause 7.4 “Mechanical tests” and all sub-clauses have been deleted;
— Clause 9 “Marking” was technically updated;
— Annex A “Transformation formulae” has been deleted;
— A new informative Annex A on “Additional information for retinal blue light hazard exposure test method”
has been added;
— the normative references were updated;
— editorial updates.
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.

v
ISO/DIS 9680:2025(en)
Introduction
This document provides the dentist and his staff with means to enable them to work with optimum visual
ease and comfort, i.e. a visual acuity of 90 % to 100 % according to zone, without adversely affecting their
perception of colour or causing excessive fatigue or photobiological injury.
In this document, the safety of an operating light is assessed in combination with its power supply. Such
power supplies may be incorporated in dental units or dental patient chairs.
Any item of equipment recommended by the manufacturer for use in conjunction with an operating light
should not render the equipment unsafe nor affect its qualities adversely.
IEC 60598-1 has been taken into account during the preparation of this document.
IEC 60601-1 specifies requirements pertaining to the basic safety and essential performance of medical
electrical equipment and medical electrical systems. IEC 80601-2-60 specifies requirements pertaining
to the basic safety and essential performance of dental units, dental patient chairs, dental handpieces and
dental operating lights. Requirements of IEC 60601-1 and IEC 80601-2-60 applicable to operating lights are
not duplicated in this document.

vi
DRAFT International Standard ISO/DIS 9680:2025(en)
Dentistry — Operating lights
1 Scope
This document specifies requirements and test methods for operating lights used in the dental treatment
and intended for illuminating the oral cavity of patients. It also contains specifications on the instructions
for use, marking and packaging.
This document applies to operating lights, irrespective of the technology of the light source.
This document excludes auxiliary light sources and those intended for patient contact, for example, from
dental handpieces and dental headlamps, fiberoptic intraoral operating light and also operating lights which
are specifically designed for use in oral surgery.
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 9687, Dentistry — Graphical symbols for dental equipment
ISO 14971, Medical devices — Application of risk management to medical devices
ISO 15223-1, Medical devices — Symbols to be used with information to be supplied by the manufacturer — Part
1: General requirements
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
ISO 17664-1, Processing of health care products — Information to be provided by the medical device
manufacturer for the processing of medical devices — Part 1: Critical and semi-critical medical devices
ISO 17664-2, Processing of health care products — Information to be provided by the medical device
manufacturer for the processing of medical devices — Part 2: Non-critical medical devices
ISO/CIE 19476, Characterization of the performance of illuminance meters and luminance meters
ISO 21530, Dentistry — Materials used for dental equipment surfaces — Determination of resistance to
chemical disinfectants
IEC 62366-1, Medical devices — Part 1: Application of usability engineering to medical devices
IEC 62471:2006, Photobiological safety of lamps and lamp systems
CIE 224, Colour Fidelity Index for accurate scientific use
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 1942, ISO 4073, IEC 60598-1,
IEC 60601-1, CIE S 017 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 9680:2025(en)
3.1
operating light
device designed for use by an operator for illuminating the oral cavity, which either distributes, filters or
transforms the light, or does any combination of these, transmitted from one or more light sources and which
includes all parts necessary for supporting, fixing and protecting the light sources, and circuit auxiliaries
together with the means of connecting them to the supply
3.2
light-activated restorative material
dental material intended for oral use that incorporates a monomer system, the polymerization of which is
activated by light
4 Requirements
4.1 Optical requirements
4.1.1 Adjustable level of illuminance
The level of illuminance shall be adjustable. The adjustment of illuminance may be either continuous or in
discrete levels.
The manufacturer shall specify nominal values for the minimum illuminance and maximum illuminance
at a distance of 700 mm from the operating light. The maximum nominal illuminance specified by the
manufacturer shall be at least 15 000 lx. The measured minimum illuminance and maximum illuminance
shall be within 20% of the respective nominal values specified by the manufacturer.
Test in accordance with 6.2 and 6.3.2.
The requirements of 4.1.1 do not apply to any operating mode(s) intended only for use while handling light-
activated restorative materials.
4.1.2 Illumination pattern
4.1.2.1 Illumination areas and illuminance levels
The illumination pattern shall be measured to determine the maximum illuminance, E , and the following
v,max
iso-illuminance lines in accordance with 6.3.2: 0,90 × E , 0,75 × E , 0,50 × E , 0,10 × E and
v,max v,max v,max v,max
1 200 lx.
An area A is defined as the area bounded by the iso-illuminance line corresponding to 75 % of the maximum
illuminance. The border of area A shall be on or outside of an ellipse with a horizontal axis of 50 mm and a
vertical axis of 25 mm, in which the horizontal axis and vertical axis of the ellipse are aligned with the major
axis and minor axis of the illumination pattern, respectively (see Figure 1). The illuminance shall not be less
than 75 % of E throughout the ellipse. Test in accordance with 6.3.2.
v,max
An area B is defined as the area bounded by the iso-illuminance line corresponding to 50 % of the maximum
illuminance. The border of area B shall be on or outside of an ellipse with a horizontal axis of 80 mm and a
vertical axis of 40 mm and with the same axes as the smaller ellipse associated with area A (see Figure 2).
Test in accordance with 6.3.2.

ISO/DIS 9680:2025(en)
Dimensions in millimetres
Key
A illumination area A
Figure 1 — Example of illumination pattern which satisfies the requirement for area A
Dimensions in millimetres
Key
B illumination area B
Figure 2 — Example of illumination pattern which satisfies the requirement for area B
4.1.2.2 Illuminance uniformity
The illuminance shall decrease in intensity progressively and smoothly toward the pattern edge.
Test in accordance with 6.3.3.

ISO/DIS 9680:2025(en)
4.1.3 Illuminance in patient's eyes
An area C is defined as the area bounded by the iso-illuminance line corresponding to 90 % of the maximum
illuminance. The level of illuminance at all points on or above a horizontal line 60 mm above the uppermost
point of area C shall not be greater than 1 200 lx (see Figure 3).
The operating light should be capable of rotating about the x-, y- and z-axes of the Cartesian coordinate
system to allow the operator maximum flexibility in positioning the operating light while preventing
excessive illuminance in the patient’s eyes.
EXAMPLE 1 Rotation of the operating light about the x-, y- and z-axes of the Cartesian coordinate system can be
achieved by three rotational pivot axes incorporated into the positioning arm of an operating light, even if the three
rotational pivot axes are not perpendicular to one another.
EXAMPLE 2 Rotation of the operating light about the x-, y- and z-axes of the Cartesian coordinate system can be
achieved by a ball-and-socket joint incorporated into the positioning arm of an operating light.
Test in accordance with 6.3.4.
Dimensions in millimetres
Key
C illumination area C
Figure 3 — Example of illumination pattern which satisfies the requirement for limiting illuminance
in the patient’s eyes
4.1.4 Chromatic uniformity
No perceptible chromatic variation (colour separation) of the light incident upon the measuring screen shall
be visible in area A and area B.
Test in accordance with 6.3.5.

ISO/DIS 9680:2025(en)
4.1.5 Chromaticity and correlated colour temperature
Over the full range of illuminance levels, the correlated colour temperature shall be in the range of 3 600 K
to 6 400 K within areas A and B of the illuminance pattern. D (the perpendicular distance in the 1960
uv
CIE Uniform Chromaticity Scale (u,v) between the Planckian locus and the chromaticity coordinates of the
operating light) shall be within the range of -0,01 to +0,01.
For reference the chromaticity limits in CIE (u,v) coordinates are depicted in Figure 4.
Preferably, when the operating light is adjusted to the maximum illuminance level, the correlated colour
temperature should be between 4 500 K and 6 400 K.
Test in accordance with 6.3.6.
The requirements of 4.1.5 do not apply to any operating modes intended only for use while handling light-
activated restorative materials.
Key
v 1960 CIE Uniform Chromaticity Scale v-coordinate
u 1960 CIE Uniform Chromaticity Scale u-coordinate
Planckian locus
Chromaticity limits
Figure 4 — Chromaticity limits in CIE (u,v) coordinates
4.1.6 Shadow
The hard shadow of a disc with 20 mm diameter at a distance of 50 mm shall have no dimension greater
than 12 mm.
Test in accordance with 6.3.7.

ISO/DIS 9680:2025(en)
4.1.7 Colour fidelity
For general illumination of the oral cavity, the operating light shall have a general colour fidelity index, R , of
f
at least 85.
NOTE The importance of accurately assessing colour in dental diagnosis and treatment while using an operating
light supports specifying R as the measure for colour fidelity in this document even though CIE 224 indicates that R is
f f
not intended as a universal replacement for the general colour rendering index, R , at this time. The decision to specify
a
R in this document was made in consultation with CIE.
f
Test in accordance with 6.3.8.
The requirements of 4.1.7 do not apply to any operating modes intended only for use while handling light-
activated restorative materials.
4.1.8 Actinic UV hazard exposure for the skin and eye
The risk group classification of the operating light for actinic ultraviolet hazard (E ) shall be Risk Group 1
s
or lower, as specified in IEC 62471:2006, 6.1, when tested under the conditions specified in 6.3.9. Unless
the operating light is classified as an exempt group for actinic ultraviolet hazard, the permissible exposure
duration, t , per IEC 62471:2006, 4.3.1 shall be calculated in accordance with 6.3.9.
max
Compliance with this requirement shall be verified either by documentation (e.g. test report by the light
source manufacturer) which verifies that all of the light sources used in the operating light do not emit in the
applicable wavelength range (200 nm to 400 nm), or by testing in accordance with 6.3.9.
4.1.9 Near-UV hazard exposure for the eye
The risk group classification of the operating light for near-UV hazard (E ) shall be Risk Group 1 or lower,
UVA
as specified in IEC 62471:2006, 6.1, when tested under the conditions specified in 6.3.10.
Unless the operating light is classified as exempt group for near-UV hazard, the permissible exposure
duration, t , per IEC 62471:2006, 4.3.2 shall be calculated in accordance with 6.3.10.
max
Compliance with this requirement shall be verified either by documentation (e.g. test report by the light
source manufacturer) which verifies that all of the light sources used in the operating light do not emit in the
applicable wavelength range (315 nm to 400 nm), or by testing in accordance with 6.3.10.
4.1.10 Retinal blue light hazard exposure
The risk group classification for retinal blue light hazard (L ) per IEC 62471:2006, 6.1 shall be Risk Group 1
B
or lower when tested under the conditions specified in 6.3.11.
Unless the operating light is classified as exempt group for retinal blue light hazard, the permissible exposure
duration, t , per IEC 62471:2006, 4.3.3 shall be calculated in accordance with 6.3.11.
max
Test in accordance with 6.3.11.
4.1.11 Single fault condition for photobiological safety
Analysis under single fault condition shall be applied to the requirements for actinic UV exposure for skin and
eye (see 4.1.8), near-UV exposure for the eye (see 4.1.9) and retinal blue light hazard exposure (see 4.1.10).
The operating light shall be considered single fault safe (IEC 60601-1:2005+AMD1:2012+AMD2:2020, 4.7) if
the risk group classification of the operating light does not exceed Risk Group 2 given in IEC 62471:2006, 6.1
under single fault condition.
NOTE 1 A single fault condition, such as a short circuit or an open circuit of any component other than a component
with high-integrity characteristics or a software failure, can lead to a higher LED driving current, increased light
emission and a higher photobiological risk group classification.

ISO/DIS 9680:2025(en)
NOTE 2 Analysis of the photobiological safety in single fault condition can be conducted based on the change in
illuminance under single fault condition relative to illuminance under normal conditions if the emission spectrum in
single fault condition is equivalent to the emission spectrum in normal conditions.
4.1.12 Heat due to optical radiation
2 2
The irradiance over the wavelength range of 300 nm to 2 500 nm shall be ≤350 W/m (35 mW/cm ) at the
maximum illuminance level at a distance of 700 mm from the operating light.
Test in accordance with 6.3.12.
4.1.13 Compatibility with light-activated restorative materials
If the operating light is equipped with a setting intended for use while handling light-activated restorative
materials, the maximum illuminance in this setting shall be at least 6 500 lx and the camphorquinone-
2 2
weighted irradiance shall be less than 3,0 W/m (0,3 mW/cm ) when tested under the conditions specified
in 6.3.13. The camphorquinone-weighted irradiance is the integral of the product of the operating light
irradiance spectrum and the normalized absorption spectrum of camphorquinone over the wavelength
range of 400 nm to 515 nm (see 6.3.13).
NOTE The photo-initiator systems of commercial dental restorative materials are currently based on one or more
of the following: camphorquinone, 1-phenyl-1,2 propanedione (PPD), or acylphosphine oxides. Each of these photo-
initiators has a different absorbance spectrum. Since the absorbance spectrum of camphorquinone extends to longer
wavelengths than the other photo-initiators, the overlap with the emission spectrum of operating lights is greatest
with camphorquinone. Therefore, the camphorquinone absorbance spectrum is expected to represent the worst-case
challenge for evaluating possible effects of dental operating lights on light-activated restorative materials.
Test in accordance with 6.3.13.
4.2 Mechanical requirements
4.2.1 Operating controls
Operating controls shall be designed and located to minimize accidental activation. Graphical symbols for
operating controls and performance shall be in accordance with ISO 9687.
4.2.2 Stability after positioning
Operating lights should be free from apparent drift when positioned.
4.2.3 Expelled parts
The operating light shall be designed to provide protection against the effects of the shattering of its light
source if it is possible for the light source to shatter. This requirement is not relevant for LED light sources.
The operating light shall so be designed that particles from a shattering light source cannot impair safety.
This shall be verified by appropriate risk analysis in accordance with ISO 14971.
4.3 Reprocessing
All exterior touchable parts of the operating light shall be suitable for reprocessing using the agents and
methods recommended by the manufacturer without deterioration of surfaces or labelling.
The manufacturer shall provide information on the reprocessing for the operating light in accordance with
ISO 17664-1 and ISO 17664-2, as applicable. Preferably, the handles should be sterilizable or capable of
accommodating reusable, sterilizable covers.
Testing of resistance against cleaning and disinfection shall be carried out in accordance with ISO 21530.

ISO/DIS 9680:2025(en)
4.4 Electrical requirements
Operating lights shall be suitable for continuous operation. Conformity shall be verified by checking the
manufacturer’s documentation.
NOTE The designation of continuous operation is relevant to determining the applicability of certain electrical
requirements of IEC 60601-1 and IEC 80601-2-60.
4.5 Usability
Usability evaluation shall be carried out following the process described in IEC 62366-1.
Testing shall be carried out in accordance with IEC 62366-1.
5 Sampling
All type tests shall be made on one representative sample of the operating light.
6 Testing
6.1 General
All tests described in this document are type tests.
Testing shall be performed at an ambient temperature of (23 ± 2) °C. The relative humidity shall be between
30 % and 70 %.
All measurements of optical radiation shall be traceable to the international system of units (SI) implemented
through the requirements of ISO/IEC 17025.
6.2 Visual inspection
Visual inspection shall be performed at normal visual acuity without magnification.
6.3 Optical tests
6.3.1 Test set-up
Aim the light beam at a measuring screen, perpendicular to the optical axis, at a distance of 700 mm
measured from the external most forward part of the operating light from which light is emitted.
Adjust the controls for illumination during the tests at the setting of the maximum illuminance level and
operate until the irradiance and colour have stabilized, as determined by monitoring the running average
of the measurements, before collecting measurements for the tests specified in 6.3.2 through 6.3.13 unless
otherwise specified.
Establish a rectangular coordinate system in the measurement plane with the origin of coordinates (i.e. the
coordinate axis intersection point) centrally placed in the zone of maximum illumination level and with the
x-axis parallel to the major axis of the illumination pattern. If there is a marked cut-off in the y-direction,
take this as the positive direction. If there is not a marked cut-off in the y-direction, arbitrarily select a
direction to be the positive direction.
For tests specifying visual assessment of the illuminance pattern, place a uniform, neutral, diffusely
reflecting, flat white screen in the measurement plane. For tests requiring instrumented measurements,
place the specified detector in the measurement plane unless otherwise specified.
Perform optical tests in a room where light from other sources and reflected light from room surfaces are
negligible.
ISO/DIS 9680:2025(en)
If the operating light is designed to be used at a target distance other than 700 mm, testing shall also be
performed at the intended operating distance.
6.3.2 Level of illuminance and illuminance pattern
Use the test set-up as described in 6.3.1.
Measure the illuminance levels with a photometer calibrated in accordance with ISO/CIE 19476 and having
an acceptance aperture with a diameter of 10 mm.
Moving the photometer within the measurement plane, make measurements at rectilinear coordinates not
more than 5 mm apart, such that all points within the illuminance pattern having an illuminance greater
than 600 lx are measured.
A photometer that can indirectly record the illuminance distribution with one measurement, i.e. an imaging
luminance measurement device (ILMD), may be used for this purpose. In such a case, the illuminance
pattern is normally projected onto a flat, uniform, diffusely reflecting screen positioned in the measurement
plane and the luminance distribution of the reflected light measured using the ILMD. The uniformity and
directional response of the reflectance characteristics of the screen shall be evaluated and either corrected
for or taken into account in the measurement uncertainties.
Record the measurements and their location. Determine the maximum illuminance, E . Use linear
v,max
interpolation of measurements to calculate and plot the following iso-illuminance lines specified in 4.1.2.1:
0,90 × E , 0,75 × E , 0,50 × E , 0,10 × E and 1 200 lx. Check whether the requirements given in
v,max v,max v,max v,max
4.1.1 and 4.1.2.1 are fulfilled.
6.3.3 Illuminance uniformity
Use the test set-up as described in 6.3.1.
The requirement is fulfilled if no bright rings or bright spots outside of the central maximum are visually
apparent.
6.3.4 Illuminance in the patient’s eyes
Using the illuminance pattern data from 6.3.2, determine the coordinates of the uppermost point of area
C (i.e. the point along the iso-illuminance line corresponding to 90 % of the maximum illuminance which
is farthest from the horizontal axis in the direction of the patient’s eyes, i.e. positive y-direction). Plot a
horizontal line 60 mm above the uppermost point of area C. Check whether the illuminance at any point
along or above the horizontal line exceeds 1 200 lx (see Figure 3).
To confirm whether there are any areas of brightness above the horizontal line, place a flat white screen in
the measurement plane. Observe whether there are areas of brightness above the horizontal line 60 mm
above the uppermost point of area C when viewed by a person with normal visual acuity at a distance of
50 cm to 75 cm. If any areas appear brighter than along the horizontal line 60 mm above the uppermost
point of area C, measure the illuminance in those areas using a calibrated photometer, as described above.
Record the measurements and their location. Check whether the requirement specified in 4.1.3 is fulfilled.
6.3.5 Chromatic uniformity
Adjust the room lighting to an illuminance level in the range of 1 % to 3 % of the maximum illuminance of
the operating light, measured at the centre of the measurement plane with a calibrated illuminance meter
oriented toward the room light source. Place a flat white screen in the measurement plane and illuminate
it with the operating light. Use three people with normal colour vision to observe whether there are any
colour non-uniformities within area A and area B when viewed at a distance of 50 cm to 75 cm. The normal
colour vision of the observers shall be verified within the past five years by at least one of the following:
— evaluation for colour vision by a medical practitioner or other appropriately trained person;

ISO/DIS 9680:2025(en)
— the Ishihara colour vision test, either digitally or physically using colour assessment cards; or
— the Richmond HRR Pseudoisochromatic Plates 4th edition colour vision test, either digitally or physically
using colour assessment cards (Good-Lite, USA).
Corrective untinted lenses may be worn.
6.3.6 Chromaticity and correlated colour temperature
Use the test set-up as described in 6.3.1 with the operating light set at maximum light output.
Determine the chromaticity coordinates at the point of maximum illuminance in the measurement plane,
using a tristimulus colourimeter or spectroradiometer and software with the capability to calculate
correlated colour temperature and D . Check whether the measured values for correlated colour
uv
temperature and D comply with the requirements specified in 4.1.5.
uv
Repeat the test at each illuminance level of the operating light. If the operating light has continuous
illuminance adjustment or more than three illuminance levels, it is acceptable to test at the maximum
illuminance level, minimum illuminance level and one illuminance level at approximately the midpoint of the
illuminance range.
6.3.7 Shadow
Place the operating light to be tested at a distance of 700 mm from a measuring screen marked with a
rectangular coordinate system (see Figure 5), with the light beam normal to the measuring screen and the
illuminance pattern axes coincident with the measuring screen coordinates.
Place a support column outside the measurement area, supporting a 20 mm diameter disc that is 1-mm thick
and opaque. Position the disc parallel to th
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