IEC TR 62471-2:2009

Photobiological safety of lamps and lamp systems - Part 2: Guidance on manufacturing requirements relating to non-laser optical radiation safety

IEC/TR 62471-2:2009(E) provides the basis for optical radiation safety requirements of non-laser products, serving as a guide for development of safety requirements in vertical product standards and assisting lamp system manufacturers in the interpretation of safety information provided by the lamp manufacturers. This report provides guidance on:
- requirements for optical radiation safety assessment;
- allocation of safety measures;
- labelling of products.
This technical report does not address safety requirements of intentional exposure to optical radiation from sun tanning equipment, ophthalmic instruments or other medical/cosmetic devices whose specific safety issues are addressed through appropriate standards.

General Information

• Status: Withdrawn
• Publication Date: 05-Aug-2009
• Withdrawal Date: 20-May-2021
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.140.01 - Lamps in general
• ICS: 31.260 - Optoelectronics. Laser equipment
• Technical Committee: TC 76 - Optical radiation safety and laser equipment
• Drafting Committee: WG 9 - TC 76/WG 9
• Current Stage: WPUB - Publication withdrawn
• Start Date: 21-May-2021
• Completion Date: 21-May-2021

Standards Content (Sample)

IEC/TR 62471-2 ®
Edition 1.0 2009-08
TECHNICAL
REPORT
colour
inside
Photobiological safety of lamps and lamp systems –
Part 2: Guidance on manufacturing requirements relating to non-laser optical
radiation safety
IEC/TR 62471-2:2009(E)
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IEC/TR 62471-2 ®
Edition 1.0 2009-08
TECHNICAL
REPORT
colour
inside
Photobiological safety of lamps and lamp systems –
Part 2: Guidance on manufacturing requirements relating to non-laser optical
radiation safety
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
X
ICS 29.140 ISBN 978-2-88910-736-0
– 2 – 62471-2/TR © IEC:2009(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references .7
3 Terms and definitions .7
4 Risk groups applied for optical radiation safety assessments.10
4.1 Basis for optical radiation safety classification.10
4.2 Assessment criteria .10
4.3 Application-related issues .10
4.3.1 Near-infrared sources.10
4.3.2 “Point sources” .11
4.3.3 Application-related vertical standards .11
5 Guidelines for lamp and lamp system manufacturers on how to apply IEC 62471 .11
5.1 Limit values.11
5.1.1 General .11
5.1.2 Limits provided in irradiance/radiant exposure .12
5.1.3 Limits provided in (time integrated) radiance .12
5.2 Guidelines for lamp/LED manufacturers .12
5.2.1 General .12
5.2.2 Measurement conditions.12
5.2.3 User information .13
5.3 Guidelines for lamp system/luminaire manufacturers .13
5.3.1 General .13
5.3.2 Sources for general lighting service (GLS).13
5.3.3 Multi-purpose lamps .14
5.3.4 Determination of the hazard distance.14
5.4 Labelling .15
5.5 Other information provisions.16
6 Allocation of safety measures .17
6.1 General .17
6.2 Maximum acceptable viewer-related risk .18
Annex A (informative) Radiance and ocular hazards from extended sources.20
Annex B (informative) Determination of hazard distances .26
Annex C (informative) Sources for general lighting service (GLS) .36
Annex D (informative) Lamps and lamp systems with integrated, attached beam-
shaping or projection optics.41
Bibliography.45

Figure 1 – Example of graphic presentation of distant dependent emission hazard
values.15
Figure 2 – Example of warning label for a lamp with multiple hazard spectral regions .17
Figure A.1 – Invariance of radiance with distance from an extended source.21
Figure A.2 – Usual measurement conditions for the determination of radiance and time
integrated radiance .

62471-2/TR © IEC:2009(E) – 3 –
Figure A.3a – Source size larger than the FOV (overfilled).23
Figure A.3b – Source size smaller than the FOV (under-filled) .23
Figure A.3 – Source sizes.23
Figure A.4 – B(λ)-weighted radiance distribution of a state-of-the-art “pc-white” LED
component.24
Figure B.1 – Normalized correlation between radiance L and corresponding irradiance
E for varying values of source diameter and distance .27
Figure B.2 – Direct intra-beam viewing of an arc searchlight showing a magnification of
the actual arc.29
Figure B.3 – Calculated flash distance of LEDs depending on the individual half
intensity angle θ of the spatial emission.30
Figure B.4 – Actinic UV-related safe use conditions for the example radiator .32
Figure B.5 – Distance-dependant (spectrally weighted) Exempt Risk Group limits for
the spatially averaged radiance of a halogen lamp of 7 mm source size.34
Figure C.1 – Measured spatially averaged radiance.37
Figure C.2 – Relationships between illuminance of 500 lux and source luminance
[cd/m ] (indicated) for several source sizes and distances of some typical luminances.38
Figure D.1 – Ultraviolet and infrared filtering by projection optics.41
Figure D.2 – Magnified apparent source size of the filament in an incandescent
projection lamp .42
Figure D.3 – Examples of projection optics .42
Figure D.4 – Formation of a virtual LED chip image by the integrated lens.43
Figure D.5 – Imaging of the apparent source and measurement condition for the
assessment of sources with built-in or attached projection optics.43

Table 1 – Hazard-related risk group labelling of lamp systems.16
Table 2 – Explanation of labelling information and guidance on control measures.17
Table 3 – Maximum acceptable risk group of products assessed for viewer-related risk
under application specific conditions.19
Table B.1 – Spatially averaged radiance .35
Table C.1 – Risk group-related inverse square law and hazard distances .37
Table C.2 – Risk group-related hazard distances (in m) for halogen lamp of 7 mm
7 -2
source diameter and with luminance of 3 × 10 cd⋅m .39

– 4 – 62471-2/TR © IEC:2009(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PHOTOBIOLOGICAL SAFETY OF LAMPS AND LAMP SYSTEMS –

Part 2: Guidance on manufacturing requirements
relating to non-laser optical radiation safety

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC 62471-2, which is a technical report, has been prepared by Technical Committee 76:
Optical radiation safety and laser equipment
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
76/396/DTR 76/410/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.

62471-2/TR © IEC:2009(E) – 5 –
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 62471 series, published under the general title Photobiological
safety of lamps and lamp systems, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

– 6 – 62471-2/TR © IEC:2009(E)
INTRODUCTION
Optical radiation hazards from all types of lamps or other broadband light sources are
assessed by the application of IEC 62471:2006 (Edition 1), Photobiological safety of lamps
and lamp systems. IEC 62471 covers LEDs as well as incandescent, low and high pressure
gas-discharge, arc and other lamps. It also covers electrically-powered optical radiation
sources that are not lamps. The standard provides a risk group classification system for all
lamps and lamp systems, and the measurement conditions are well developed. IEC 62471
does not include manufacturing or user safety requirements that may be required as a result
of a lamp or lamp system being assigned to a particular risk group. The safety requirements
for lamp systems necessarily vary and are best dealt with in vertical standards. This Part 2
provides the basis for safety requirements dependent upon risk group classification and
examples thereof. The assigned risk group of a product may be used to assist with risk
assessments, e.g. for occupational exposure in workplaces. National requirements may exist
for the assessment of products or occupational exposure.
NOTE 1 There are some instances where the IEC 60825 laser product standards may be useful for a nearly
“point” source, as in an LED fibre source or a superluminescent diode (see 3.16).
NOTE 2 IEC 62471 is currently being revised and will be published as IEC 62471-1.

62471-2/TR © IEC:2009(E) – 7 –
PHOTOBIOLOGICAL SAFETY OF LAMPS AND LAMP SYSTEMS –

Part 2: Guidance on manufacturing requirements
relating to non-laser optical radiation safety

1 Scope
This technical report provides the basis for optical radiation safety requirements of non-laser
products, serving as a guide for development of safety requirements in vertical product
standards and assisting lamp system manufacturers in the interpretation of safety information
provided by the lamp manufacturers.
This report provides guidance on:
• requirements for optical radiation safety assessment;
• allocation of safety measures;
• labelling of products.
This technical report does not address safety requirements of intentional exposure to optical
radiation from sun tanning equipment, ophthalmic instruments or other medical/cosmetic
devices whose specific safety issues are addressed through appropriate standards.
2 Normative references
The following referenced documents are indispensable for the application 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.
IEC 62471, Photobiological safety of lamps and lamp systems
IEC 60825 (all parts), Safety of laser products
IEC 60050-845, International Electrotechnical Vocabulary – Chapter 845: Lighting
IEC 60417, Graphical symbols for use on equipment
3 Terms and definitions
For the purposes of this document, the terms and definitions of IEC 62471 and the following
additional terms and definitions apply.
3.1
controlled access location
location where an engineering and/or administrative control measure is established to restrict
access except to authorised personnel with appropriate safety training
3.2
exposure hazard value
EHV
value defined as follows:
Exposure level (distance,exposure time)
EHV (distance,exposure time) =
Exposure limit value
– 8 – 62471-2/TR © IEC:2009(E)
The EHV is greater than 1 when the exposure level (3.3) exceeds the exposure limit value
(3.4)
3.3
exposure level
EL
level of exposure from a source at a location in space for a stated duration
3.4
exposure limit value
ELV
maximum level of exposure of optical radiation to the eye or skin that is not expected to result
in adverse biological effects. These ELVs are used to determine hazard distances in respect
to foreseeable photobiological effects
3.5
hazard distance
HD
distance from the source at which the EL equals the appropriate exposure limit value (ELV)
3.6
intended viewing
deliberate act of an individual to either look at a source of optical radiation or at a virtual
source, such as a reflection
3.7
intended use
usage of a product, process or service in accordance with specifications, instructions and
information provided by the manufacturer or supplier
3.8
lamp
electrically powered device emitting optical radiation in the wavelength range between 200 nm
and 3 000 nm, with the exception of laser radiation
3.9
lamp system
electrically operated product incorporating a lamp or lamps, including fixtures and
incorporated electrical or electronic components, generally as intended by the manufacturer to
be used (for illumination purposes - luminaire)
NOTE 1 Lamp systems may include diffusers, enclosures and/or beam modifying optics.
NOTE 2 For the purpose of this technical report, a lamp system may incorporate a lamp that does not serve as the
primary function of the product, e.g. an indicator lamp or an illumination lamp inside a refrigerator.
3.10
modifying optics
optical components, such as filters, lenses and reflectors, which change the characteristics of
the optical radiation from a lamp when incorporated into a lamp system
3.11
non-laser optical radiation
incoherent optical radiation generated by a process other than stimulated emission

62471-2/TR © IEC:2009(E) – 9 –
3.12
restricted access location
location which is normally inaccessible by the general public, including workers, visitors and
residents in the immediate vicinity, by means of engineering or administrative control
measures but is accessible to authorised personnel that may not have specific safety training
3.13
small source
source or apparent source with an angular subtense smaller than the angle of acceptance γ
that should be applied according to a risk assessment or classification.
NOTE This may result in the spatially averaged radiance (3.15) of a source or apparent source being averaged
over a larger area than would be applied for the source radiance (3.14).
3.14
source radiance
radiance of the emitting element of the source (see IEV 845-01-34). However, the applicable
acceptance angle should not be smaller than 1,7 mrad
Symbol: L
NOTE It is defined to differentiate from spatially averaged radiance (3.15).
3.15
spatially averaged radiance
radiance spatially averaged over a given angle of acceptance to account for physiological
factors such as eye-movements (sometimes referred to as “physiological radiance”). The
spatially average radiance may be lower than the source radiance (see 3.14)
Symbol: L
sa
3.16
superluminescent diode
edge-emitting semiconductor light source based on superluminescence. It combines the high
power and brightness of laser diodes with the low coherence of conventional light-emitting
diodes. Its emission band is 20 nm to 100 nm wide
3.17
unintentional viewing
condition when eye exposure to optical radiation is not intended
3.18
unintentional skin exposure
condition when skin exposure to optical radiation is not intended
3.19
viewer-related risk
risk for intended or unintended viewers of a source under application-specific realistic
conditions
NOTE In order to be independent of the use condition, the risk group classification of lamps and lamp systems is
based on worst case assumptions of exposure duration, pupil size and viewing distance. However, the emission of
lamps is often divergent and when a lamp is integrated into a product, depending on product design and its
application, these assessment conditions may become inappropriate. In this case, the product may be assessed at
the minimum distance and maximum exposure duration representative for the application-specific conditions of
foreseeable access.
– 10 – 62471-2/TR © IEC:2009(E)
4 Risk groups applied for optical radiation safety assessments
4.1 Basis for optical radiation safety classification
IEC 62471 provides the method to determine the risk group of any lamp or any product
incorporating a lamp. The risk groups in IEC 62471 indicate the degree of risk from potential
optical radiation hazards and minimise the need for further measurements. The risk groups
were developed based upon decades of lamp use experience and the analysis of accidental
injuries related to optical radiation emission (where injuries were, generally, quite rare except
from ultraviolet-emitting lamps or arc lamps). There are four basic risk groups:
• Exempt Group (RG 0), where no optical hazard is considered reasonably foreseeable,
even for continuous, unrestricted use. Typical examples are most frosted incandescent
lamps and fluorescent lamps used in domestic applications;
• Risk Group 1 (RG 1) products are safe for most use applications, except for very
prolonged exposures where direct ocular exposures may be expected. An example of a
Risk Group 1 product is a domestic battery operated torch (flashlight);
• Risk Group 2 (RG 2) products generally do not pose a realistic optical hazard if aversion
responses limit the exposure duration or where lengthy exposures are unrealistic;
• Risk Group 3 (RG 3) products pose a potential hazard even for momentary exposures, and
system safety requirements are generally essential.
IEC 62471 does not provide manufacturing requirements and control measures. These issues
should be addressed in application-specific vertical standards (see 4.3.3). However, in order
to provide a consistent approach across products, the (non-normative) labelling requirements
are outlined in this technical report (see 5.4).
4.2 Assessment criteria
The standard measurement conditions consider the emission spectrum and, depending on the
type of hazard, either irradiance or spatially averaged radiance to determine risk to the eye
and/or the skin. The measurement conditions are related to potentially hazardous viewing
conditions and take into consideration physiological factors of the eye, such as
accommodation, pupil size, the aversion responses and eye movements (saccades).
IEC 62471 distinguishes between lamps intended for general lighting service (GLS) and lamps
intended for use in other applications such as for germicidal use, heating, signalling, data
transfer or others. Assessment and measurement conditions are different for these two
groups:
• GLS - the hazard values should be quoted as irradiance or spatially averaged radiance
values at a distance which produces an illuminance of 500 lux;
• other applications – the hazard values should be determined at a distance of 200 mm from
the source.
Different application groups define a range of operational, maintenance and servicing
conditions. If the assessment applied to different application groups in a vertical standard
justifies it, the measurement conditions in IEC 62471 can be modified for specific application
groups.
4.3 Application-related issues
4.3.1 Near-infrared sources
The limits set for the infrared (IR) spectral region were originally intended for applications of
large IR-radiators with a significant amount of IR-A and IR-B radiation. The limits protect the
cornea or lens of the eye against long-term thermal effects (e.g. cataract). Thus, the limits
should be applied where the application is likely to result in chronic and lengthy exposures of

62471-2/TR © IEC:2009(E) – 11 –
the eye for periods greater than 1 000 s and the daily averaged irradiance is expected to be at
. -2
least 100 W m . The primary objective is to minimise heating of the lens and cornea.
4.3.2 “Point sources”
There may be a small number of applications where an incoherent optical radiation source
appears as a nearly monochromatic “point” source and should be considered within a laser
safety standard framework. Generally, this will only apply to: superluminescent diodes (SLDs)
(see 3.16), which resemble “point sources”; and LEDs which are employed in optical fibre
communications, where the fibre source also resembles a very small, or “point” source. The
user is referred to IEC 60825-1 for SLDs and to IEC 60825-2 for optical fibre communication
systems.
4.3.3 Application-related vertical standards
The requirements in vertical standards may:
– limit the source risk group that can be used in a given application;
– require specific performance features based upon the risk group specifications; or
– specify application-specific control measures.
Basic guidance, based on the likelihood of direct source viewing, is provided in Clause 6.
Vertical standards should be guided by the principle that it is not necessary to reduce optical
radiation exposure to as low as reasonably achievable. However, as a general guideline,
needless emissions that would produce unnecessary human exposure should be minimised.
The hierarchy of applicable safety measures should follow the internationally accepted priority
ranking of manufacturer safety measures. That is, engineering controls (e.g., filters, shielding,
etc) are the highest priority, followed by administrative measures (such as warnings and
labels, see 5.4) and then personal protective equipment as the last resort. Details should be
provided in application-specific vertical standards.
5 Guidelines for lamp and lamp system manufacturers on how to apply IEC
5.1 Limit values
5.1.1 General
It should be noted that the risk group classification system of IEC 62471 is primarily applied to
lamps. However, in terms of product safety, the lamp system manufacturer has responsibility
for assessing the final lamp system product. Because of different technical tasks and needs,
manufacturers of lamp systems or luminaires might have limited capabilities for tests and
measurements and they commonly rely on the lamp/LED data provided by the lamp/LED
manufacturer. Therefore, guidance is provided on how and when lamp system manufacturers
may rely on data provided by the lamp manufacturer.
There are many types of lamps for which the intended applications are known. For instance,
for conventional light sources, the modifications of the safety-related optical features of the
incorporated lamp by the lamp system manufacturer are generally not significant. In most
cases there is a single conventional lamp type (light bulb) used for a luminaire and the lamp
system manufacturer only adds a fixture and a power supply. In these cases, the lamp data
are usually directly transferable to the lamp system. The assessment and risk group
classification of the lamp can be used by the lamp system manufacturer for classification of
the lamp system. However, other types of lamps may need detailed consideration.
The limit values of the safety standard are provided in two different quantities, which require
separate consideration.
– 12 – 62471-2/TR © IEC:2009(E)
5.1.2 Limits provided in irradiance/radiant exposure
In the spectral ranges 200 nm to 400 nm and 1 400 nm to 3 000 nm where the emission limits
in IEC 62471 are provided in irradiance or radiant exposure, the measurements of a single
lamp can not simply be transferred directly to a lamp system but require an analysis of the
optical additivity to determine the system risk group.
When a lamp is employed with additional integrated or attached modifying or projection
optics, this lamp system should be considered as a different product and the lamp system
manufacturer should provide the new risk group safety classification.
NOTE Additional optics primarily modify the irradiance of a source (i.e. may have a significant impact where the
classification is based on irradiance or radiant exposure-criteria), whereas the radiance may remain unchanged
(i.e. less impact where the classification is based on radiance-criteria).
5.1.3 Limits provided in (time integrated) radiance
In cases where the emission limits in IEC 62471 are provided in terms of spatially averaged
radiance or time-integrated spatially averaged radiance, the principle of conservation of
radiance may be used with caution. That is, if a lamp or single LED emits below the radiance
level specified (per risk group), the final lamp system or LED-array also can not exceed the
accessible emission limits. IEC 62471 requires measurements of spatially averaged radiance
(3.15) values with the consequence that the relationship between the field of view and the
source area, as it was used for the characterisation of a single component, may be changed
by the integration of the single lamp or LED into luminaries (arrays) or with the attachment of
beam-shaping optics.
Under specific conditions (see 5.2.2), the assessment of a single lamp/LED is directly
transferable to the lamp system or luminaire. The risk group will remain the same, or may be
reduced (e.g., by filters, etc.).
NOTE Since additional optics primarily modify (increase) the irradiance of a source rather than the radiance, an
evaluation should verify that the most restrictive classification criterion of the lamp system has not been changed
(from radiance to irradiance criterion).
5.2 Guidelines for lamp/LED manufacturers
5.2.1 General
The primary purpose of lamp risk-group classification by the lamp or LED manufacturer is to
inform the user or final-product manufacturer of potential hazards that may need to be
addressed in the safety design of the final product. Therefore, when a lamp is placed in Risk
Groups 1, 2 or 3, it is important for the user to be informed of which potential hazards may
require controls. If the manufacturer provides the EHV or HD for the lamp (see 5.3.4), the
determination of appropriate controls can be simplified.
5.2.2 Measurement conditions
In the range 200 nm to 400 nm or 1 400 nm to 3 000 nm where the limits in IEC 62471 are
provided in irradiance or radiant exposure, the measurements should be performed according
to IEC 62471.
In cases where the limits in IEC 62471 are provided in spatially averaged radiance or time-
integrated radiance, the source radiance (according to 3.14) data should be determined
(LEDs: operating under maximum operating conditions, such as maximum current) according
to IEC 62471. The angle of acceptance should be 1,7 mrad in any case.
NOTE These values should be compared with the risk group-specific limit values (rather than apply different
angles of acceptance). Under these conditions it can be assured that the risk group allocation of the component in
any case is directly transferable and useful to the characterisation of the final lamp system.

62471-2/TR © IEC:2009(E) – 13 –
If the use of the product is known and unambiguous, the application-specific requirements
(i.e. vertical standards) should be applied, where these exist, or subclauses 4.2 and 4.3
should be applied.
In case of multi-purpose lamps or if application-specific requirements (i.e. vertical standards)
do not exist, the measurement of single lamps and components should be performed at a
distance of 200 mm and the risk group and values should appear in the user information.
The assessment and risk group classification should be based on these values.
5.2.3 User information
The user information should include the risk group classification of the lamp that can be used
for risk group classification of a lamp system.
Information on risk group classification should be given for the intended use. Information
should be provided if application-specific conditions or requirements (as pointed out in 4.2
and 4.3 or as required by vertical standards) were applied. It should be noted that re-
classification may be necessary if the lamp is used in other applications.
In the range 200 nm to 400 nm or 1 400 nm to 3 000 nm where the classification is based on
irradiance or radiant exposure, it should be noted that the assessment of a single lamp can
not be automatically transferred to the final lamp system. However, if the integration of the
lamp into a lamp system does not change the accessible emission characteristics of the lamp,
the risk group classification of the lamp system remains the same as the risk group of the
lamp.
5.3 Guidelines for lamp system/luminaire manufacturers
5.3.1 General
The lamp risk group classification indicates necessary safety measures to reduce the risk
group required for the application as specified in vertical standards. If the risk group of the
lamp is below the maximum appropriate for the application (see Table 3), the manufacturer
should assure that the risk group is directly transferable to the lamp system.
Lamp manufacturers produce some lamp types solely intended for specific applications (4.2
and 4.3, or as required by vertical standards) and these products should be classified by the
lamp manufacturer only under the application-specific conditions, if they exist. If these
sources are modified or marketed for use for other purposes, the lamp system manufacturer
should perform the re-assessment and assign the appropriate risk group.
5.3.2 Sources for general lighting service (GLS)
IEC 62471 states that for lamps and lamp systems used for GLS the hazard values should be
reported as irradiance or spatially averaged radiance values at a distance which produces an
illuminance of 500 lux. Only lamps and lamp systems which are classified as Exempt Group
with respect to the skin hazard when assessed at the location of the 500 lux illuminance level,
should normally be used for GLS applications. In addition, if the application requires skin
access to the optical radiation from the source where the illuminance is likely to exceed
500 lux for periods of exposure longer than 1 h, the user should be warned that an exposure
assessment may be required.
NOTE The above is intended to ensure that applications are considered where, for example, the UV emission
limits may be exceeded. This may be of concern for some lamps where the emission limits are not exceeded at 500
lux, but may be exceeded at a higher illuminance level where the hands, for example, may be located during fine
detail task illumination, or where the head is closer to the source than the surface illuminated at 500 lux.
The required illuminance measurement of the GLS lamp systems takes into account
contributions from all the elements of the lamp system. In contrast to the radiance

– 14 – 62471-2/TR © IEC:2009(E)
measurement for risk group determination, the acceptance angle for the illuminance
measurement of GLS sources is not limited. When multiple lamps or modifying optics are
applied to a GLS product, the ultraviolet and infrared emission of the product in many cases
may be reduced; thus, the corresponding risk is reduced. Furthermore, if lenses or arrays
increase the 500 lux distance, the angular subtense of the component sources decrease (and
the spatially averaged radiance decreases), so that the risk remains essentially the same.
In cases where the classification by the lamp manufacturer is based on radiance or time-
integrated radiance and where irradiance-dependant hazards can be neglected (LEDs or by
the use of appropriate filters), the GLS-classification of the lamp can directly be transferred to
the lamp system/luminaire.
5.3.3 Multi-purpose lamps
The following general approach should be followed in the course of risk group determination
of lamp systems. In cases where the risk classification of the lamp is based on the most
restrictive radiance or time-integrated radiance criteria, these values remain unchanged or are
decreased by integration of the lamp into a system or by adding optical elements. Such
measures or elements, in contrast, may change the irradiance or radiant exposure produced
by a source and should be considered in cases where the risk grouping of the incorporated
lamp is based on those criteria. However, the possible variation of the most restrictive
classification criterion, i.e. from radiance to irradiance, should be considered in case of
radiance-based classification of the incorporated lamp.
5.3.4 Determination of the hazard distance
In order to be independent of the use condition, the risk group classification of lamps and
lamp systems is based on worst case assumptions of exposure duration, pupil size and
viewing distance. However, the emission of lamps is often divergent and the viewer-related
risk at a reasonable distance may not be adequately reflected by the risk classification of the
equipment, i.e. the real risk is lower.
The exposure hazard values (EHV), i.e. the excess over the applicable exposure limits, have
significant practical relevance (see 3.2). This concept can be helpful when considering
appropriate control measures: to limit either the exposure duration or the accessibility of a
source as applicable.
The EHV may be graphically presented as distance-dependent values: with increasing
distance from a lamp or lamp system the applicable hazard values decrease - see Figure 1. At
the distance X , EHV = 1, i.e. the EHV equals the applicable emission limit value. Distance X
1 1
is the hazard distance (HD) for this lamp system. At distance X , the optical radiation hazard
value exceeds the applicable emission limit value by a factor of A. At this distance, excessive
exposure to optical radiation may be reduced either by restricting exposure time by a factor of
A (if the emission limit values are expressed in terms of radiant exposure or time integrated
radiance), or by using engineering controls (such as filters) which attenuate the accessible
emission and/or personal protective means (such as eyewear, clothing) which would limit the
potential exposure to the emitted energy.

62471-2/TR © IEC:2009(E) – 15 –

Optical hazard value exceeds applicable ELV by
factor of A: reduce exposure duration by factor of
A or attenuate emission by factor of A
A
Optical hazard value = ELV
Distance X : EHV = A
Distance X : EHV = 1
0,1
X X
2 1
Distance IEC  1578/09
Figure 1 – Example of graphic presentation of distant dependent
emission hazard values
Similar to the risk group allocation of the lamp or lamp system, these hazard distance values
can also be categorized in order to determine the effective viewer-related risk (3.19) under
realistic use conditions. For instance, with increasing distance from a Risk Group 3 lamp
system (as categorised at a measurement distance of 200 mm) the risk for the viewer
stepwise decreases from Risk Group 2 (e.g. at X in Figure 1) to Risk Group 1 and to Exempt
(e.g. at X in Figure 1), at the distances where the irradiance, or from where the measured
radiance, falls below the applicable risk-group-specific emission limit.
Therefore, in addition to assigning a lamp system to a risk group, the lamp system
manufacturer should also provide such data. Where the lamp system is assigned to a risk
group above Exempt, the manufacturer should, at least, provide the hazard distance (HD) for
all risk groups below the assigned one. These risk group-related hazard distances can be
used for the determination of applicable safety measures, see Table 3.
NOTE The above example and Figure 1 apply to one limit (“hazard”) and to a specific exposure duration. Similar
data are needed for all relevant limits (“hazards”) as well as for different exposure durations.
5.4 Labelling
Usually, primary engineering control measures need to
...

IEC/TR 62471-2 ®
Edition 1.0 2009-08
TECHNICAL
REPORT
colour
inside
Photobiological safety of lamps and lamp systems –
Part 2: Guidance on manufacturing requirements relating to non-laser optical
radiation safety
IEC/TR 62471-2:2009(E)
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IEC/TR 62471-2 ®
Edition 1.0 2009-08
TECHNICAL
REPORT
colour
inside
Photobiological safety of lamps and lamp systems –
Part 2: Guidance on manufacturing requirements relating to non-laser optical
radiation safety
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
X
ICS 29.140 ISBN 978-2-88910-736-0
– 2 – 62471-2/TR © IEC:2009(E)

CONTENTS
FOREWORD.4

INTRODUCTION.6

1 Scope.7

2 Normative references .7

3 Terms and definitions .7

4 Risk groups applied for optical radiation safety assessments.10

4.1 Basis for optical radiation safety classification.10
4.2 Assessment criteria .10
4.3 Application-related issues .10
4.3.1 Near-infrared sources.10
4.3.2 “Point sources” .11
4.3.3 Application-related vertical standards .11
5 Guidelines for lamp and lamp system manufacturers on how to apply IEC 62471 .11
5.1 Limit values.11
5.1.1 General .11
5.1.2 Limits provided in irradiance/radiant exposure .12
5.1.3 Limits provided in (time integrated) radiance .12
5.2 Guidelines for lamp/LED manufacturers .12
5.2.1 General .12
5.2.2 Measurement conditions.12
5.2.3 User information .13
5.3 Guidelines for lamp system/luminaire manufacturers .13
5.3.1 General .13
5.3.2 Sources for general lighting service (GLS).13
5.3.3 Multi-purpose lamps .14
5.3.4 Determination of the hazard distance.14
5.4 Labelling .15
5.5 Other information provisions.16
6 Allocation of safety measures .17
6.1 General .17
6.2 Maximum acceptable viewer-related risk .18

Annex A (informative) Radiance and ocular hazards from extended sources.20
Annex B (informative) Determination of hazard distances .26
Annex C (informative) Sources for general lighting service (GLS) .36
Annex D (informative) Lamps and lamp systems with integrated, attached beam-
shaping or projection optics.41
Bibliography.45

Figure 1 – Example of graphic presentation of distant dependent emission hazard
values.15
Figure 2 – Example of warning label for a lamp with multiple hazard spectral regions .17
Figure A.1 – Invariance of radiance with distance from an extended source.21
Figure A.2 – Usual measurement conditions for the determination of radiance and time
integrated radiance .

62471-2/TR © IEC:2009(E) – 3 –

Figure A.3a – Source size larger than the FOV (overfilled).23

Figure A.3b – Source size smaller than the FOV (under-filled) .23

Figure A.3 – Source sizes.23

Figure A.4 – B(λ)-weighted radiance distribution of a state-of-the-art “pc-white” LED

component.24

Figure B.1 – Normalized correlation between radiance L and corresponding irradiance

E for varying values of source diameter and distance .27

Figure B.2 – Direct intra-beam viewing of an arc searchlight showing a magnification of
the actual arc.29

Figure B.3 – Calculated flash distance of LEDs depending on the individual half
intensity angle θ of the spatial emission.30
Figure B.4 – Actinic UV-related safe use conditions for the example radiator .32
Figure B.5 – Distance-dependant (spectrally weighted) Exempt Risk Group limits for
the spatially averaged radiance of a halogen lamp of 7 mm source size.34
Figure C.1 – Measured spatially averaged radiance.37
Figure C.2 – Relationships between illuminance of 500 lux and source luminance
[cd/m ] (indicated) for several source sizes and distances of some typical luminances.38
Figure D.1 – Ultraviolet and infrared filtering by projection optics.41
Figure D.2 – Magnified apparent source size of the filament in an incandescent
projection lamp .42
Figure D.3 – Examples of projection optics .42
Figure D.4 – Formation of a virtual LED chip image by the integrated lens.43
Figure D.5 – Imaging of the apparent source and measurement condition for the
assessment of sources with built-in or attached projection optics.43

Table 1 – Hazard-related risk group labelling of lamp systems.16
Table 2 – Explanation of labelling information and guidance on control measures.17
Table 3 – Maximum acceptable risk group of products assessed for viewer-related risk
under application specific conditions.19
Table B.1 – Spatially averaged radiance .35
Table C.1 – Risk group-related inverse square law and hazard distances .37
Table C.2 – Risk group-related hazard distances (in m) for halogen lamp of 7 mm
7 -2
source diameter and with luminance of 3 × 10 cd⋅m .39

– 4 – 62471-2/TR © IEC:2009(E)

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
PHOTOBIOLOGICAL SAFETY OF LAMPS AND LAMP SYSTEMS –

Part 2: Guidance on manufacturing requirements

relating to non-laser optical radiation safety

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
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5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC 62471-2, which is a technical report, has been prepared by Technical Committee 76:
Optical radiation safety and laser equipment
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
76/396/DTR 76/410/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.

62471-2/TR © IEC:2009(E) – 5 –

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts of the IEC 62471 series, published under the general title Photobiological

safety of lamps and lamp systems, can be found on the IEC website.

The committee has decided that the contents of this publication will remain unchanged until

the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in

the data related to the specific publication. At this date, the publication will be

• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

– 6 – 62471-2/TR © IEC:2009(E)

INTRODUCTION
Optical radiation hazards from all types of lamps or other broadband light sources are

assessed by the application of IEC 62471:2006 (Edition 1), Photobiological safety of lamps

and lamp systems. IEC 62471 covers LEDs as well as incandescent, low and high pressure

gas-discharge, arc and other lamps. It also covers electrically-powered optical radiation

sources that are not lamps. The standard provides a risk group classification system for all

lamps and lamp systems, and the measurement conditions are well developed. IEC 62471

does not include manufacturing or user safety requirements that may be required as a result

of a lamp or lamp system being assigned to a particular risk group. The safety requirements

for lamp systems necessarily vary and are best dealt with in vertical standards. This Part 2

provides the basis for safety requirements dependent upon risk group classification and
examples thereof. The assigned risk group of a product may be used to assist with risk
assessments, e.g. for occupational exposure in workplaces. National requirements may exist
for the assessment of products or occupational exposure.
NOTE 1 There are some instances where the IEC 60825 laser product standards may be useful for a nearly
“point” source, as in an LED fibre source or a superluminescent diode (see 3.16).
NOTE 2 IEC 62471 is currently being revised and will be published as IEC 62471-1.

62471-2/TR © IEC:2009(E) – 7 –

PHOTOBIOLOGICAL SAFETY OF LAMPS AND LAMP SYSTEMS –

Part 2: Guidance on manufacturing requirements

relating to non-laser optical radiation safety

1 Scope
This technical report provides the basis for optical radiation safety requirements of non-laser
products, serving as a guide for development of safety requirements in vertical product
standards and assisting lamp system manufacturers in the interpretation of safety information

provided by the lamp manufacturers.
This report provides guidance on:
• requirements for optical radiation safety assessment;
• allocation of safety measures;
• labelling of products.
This technical report does not address safety requirements of intentional exposure to optical
radiation from sun tanning equipment, ophthalmic instruments or other medical/cosmetic
devices whose specific safety issues are addressed through appropriate standards.
2 Normative references
The following referenced documents are indispensable for the application 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.
IEC 62471, Photobiological safety of lamps and lamp systems
IEC 60825 (all parts), Safety of laser products
IEC 60050-845, International Electrotechnical Vocabulary – Chapter 845: Lighting
IEC 60417, Graphical symbols for use on equipment
3 Terms and definitions
For the purposes of this document, the terms and definitions of IEC 62471 and the following
additional terms and definitions apply.
3.1
controlled access location
location where an engineering and/or administrative control measure is established to restrict
access except to authorised personnel with appropriate safety training
3.2
exposure hazard value
EHV
value defined as follows:
Exposure level (distance,exposure time)
EHV (distance,exposure time) =
Exposure limit value
– 8 – 62471-2/TR © IEC:2009(E)

The EHV is greater than 1 when the exposure level (3.3) exceeds the exposure limit value

(3.4)
3.3
exposure level
EL
level of exposure from a source at a location in space for a stated duration

3.4
exposure limit value
ELV
maximum level of exposure of optical radiation to the eye or skin that is not expected to result
in adverse biological effects. These ELVs are used to determine hazard distances in respect
to foreseeable photobiological effects
3.5
hazard distance
HD
distance from the source at which the EL equals the appropriate exposure limit value (ELV)
3.6
intended viewing
deliberate act of an individual to either look at a source of optical radiation or at a virtual
source, such as a reflection
3.7
intended use
usage of a product, process or service in accordance with specifications, instructions and
information provided by the manufacturer or supplier
3.8
lamp
electrically powered device emitting optical radiation in the wavelength range between 200 nm
and 3 000 nm, with the exception of laser radiation
3.9
lamp system
electrically operated product incorporating a lamp or lamps, including fixtures and
incorporated electrical or electronic components, generally as intended by the manufacturer to
be used (for illumination purposes - luminaire)
NOTE 1 Lamp systems may include diffusers, enclosures and/or beam modifying optics.

NOTE 2 For the purpose of this technical report, a lamp system may incorporate a lamp that does not serve as the
primary function of the product, e.g. an indicator lamp or an illumination lamp inside a refrigerator.
3.10
modifying optics
optical components, such as filters, lenses and reflectors, which change the characteristics of
the optical radiation from a lamp when incorporated into a lamp system
3.11
non-laser optical radiation
incoherent optical radiation generated by a process other than stimulated emission

62471-2/TR © IEC:2009(E) – 9 –

3.12
restricted access location
location which is normally inaccessible by the general public, including workers, visitors and

residents in the immediate vicinity, by means of engineering or administrative control

measures but is accessible to authorised personnel that may not have specific safety training

3.13
small source
source or apparent source with an angular subtense smaller than the angle of acceptance γ

that should be applied according to a risk assessment or classification.

NOTE This may result in the spatially averaged radiance (3.15) of a source or apparent source being averaged
over a larger area than would be applied for the source radiance (3.14).
3.14
source radiance
radiance of the emitting element of the source (see IEV 845-01-34). However, the applicable
acceptance angle should not be smaller than 1,7 mrad
Symbol: L
NOTE It is defined to differentiate from spatially averaged radiance (3.15).
3.15
spatially averaged radiance
radiance spatially averaged over a given angle of acceptance to account for physiological
factors such as eye-movements (sometimes referred to as “physiological radiance”). The
spatially average radiance may be lower than the source radiance (see 3.14)
Symbol: L
sa
3.16
superluminescent diode
edge-emitting semiconductor light source based on superluminescence. It combines the high
power and brightness of laser diodes with the low coherence of conventional light-emitting
diodes. Its emission band is 20 nm to 100 nm wide
3.17
unintentional viewing
condition when eye exposure to optical radiation is not intended
3.18
unintentional skin exposure
condition when skin exposure to optical radiation is not intended

3.19
viewer-related risk
risk for intended or unintended viewers of a source under application-specific realistic
conditions
NOTE In order to be independent of the use condition, the risk group classification of lamps and lamp systems is
based on worst case assumptions of exposure duration, pupil size and viewing distance. However, the emission of
lamps is often divergent and when a lamp is integrated into a product, depending on product design and its
application, these assessment conditions may become inappropriate. In this case, the product may be assessed at
the minimum distance and maximum exposure duration representative for the application-specific conditions of
foreseeable access.
– 10 – 62471-2/TR © IEC:2009(E)

4 Risk groups applied for optical radiation safety assessments

4.1 Basis for optical radiation safety classification

IEC 62471 provides the method to determine the risk group of any lamp or any product

incorporating a lamp. The risk groups in IEC 62471 indicate the degree of risk from potential

optical radiation hazards and minimise the need for further measurements. The risk groups

were developed based upon decades of lamp use experience and the analysis of accidental

injuries related to optical radiation emission (where injuries were, generally, quite rare except

from ultraviolet-emitting lamps or arc lamps). There are four basic risk groups:

• Exempt Group (RG 0), where no optical hazard is considered reasonably foreseeable,

even for continuous, unrestricted use. Typical examples are most frosted incandescent
lamps and fluorescent lamps used in domestic applications;
• Risk Group 1 (RG 1) products are safe for most use applications, except for very
prolonged exposures where direct ocular exposures may be expected. An example of a
Risk Group 1 product is a domestic battery operated torch (flashlight);
• Risk Group 2 (RG 2) products generally do not pose a realistic optical hazard if aversion
responses limit the exposure duration or where lengthy exposures are unrealistic;
• Risk Group 3 (RG 3) products pose a potential hazard even for momentary exposures, and
system safety requirements are generally essential.
IEC 62471 does not provide manufacturing requirements and control measures. These issues
should be addressed in application-specific vertical standards (see 4.3.3). However, in order
to provide a consistent approach across products, the (non-normative) labelling requirements
are outlined in this technical report (see 5.4).
4.2 Assessment criteria
The standard measurement conditions consider the emission spectrum and, depending on the
type of hazard, either irradiance or spatially averaged radiance to determine risk to the eye
and/or the skin. The measurement conditions are related to potentially hazardous viewing
conditions and take into consideration physiological factors of the eye, such as
accommodation, pupil size, the aversion responses and eye movements (saccades).
IEC 62471 distinguishes between lamps intended for general lighting service (GLS) and lamps
intended for use in other applications such as for germicidal use, heating, signalling, data
transfer or others. Assessment and measurement conditions are different for these two
groups:
• GLS - the hazard values should be quoted as irradiance or spatially averaged radiance
values at a distance which produces an illuminance of 500 lux;

• other applications – the hazard values should be determined at a distance of 200 mm from
the source.
Different application groups define a range of operational, maintenance and servicing
conditions. If the assessment applied to different application groups in a vertical standard
justifies it, the measurement conditions in IEC 62471 can be modified for specific application
groups.
4.3 Application-related issues
4.3.1 Near-infrared sources
The limits set for the infrared (IR) spectral region were originally intended for applications of
large IR-radiators with a significant amount of IR-A and IR-B radiation. The limits protect the
cornea or lens of the eye against long-term thermal effects (e.g. cataract). Thus, the limits
should be applied where the application is likely to result in chronic and lengthy exposures of

62471-2/TR © IEC:2009(E) – 11 –

the eye for periods greater than 1 000 s and the daily averaged irradiance is expected to be at

. -2
least 100 W m . The primary objective is to minimise heating of the lens and cornea.

4.3.2 “Point sources”
There may be a small number of applications where an incoherent optical radiation source

appears as a nearly monochromatic “point” source and should be considered within a laser

safety standard framework. Generally, this will only apply to: superluminescent diodes (SLDs)

(see 3.16), which resemble “point sources”; and LEDs which are employed in optical fibre

communications, where the fibre source also resembles a very small, or “point” source. The

user is referred to IEC 60825-1 for SLDs and to IEC 60825-2 for optical fibre communication
systems.
4.3.3 Application-related vertical standards
The requirements in vertical standards may:
– limit the source risk group that can be used in a given application;
– require specific performance features based upon the risk group specifications; or
– specify application-specific control measures.
Basic guidance, based on the likelihood of direct source viewing, is provided in Clause 6.
Vertical standards should be guided by the principle that it is not necessary to reduce optical
radiation exposure to as low as reasonably achievable. However, as a general guideline,
needless emissions that would produce unnecessary human exposure should be minimised.
The hierarchy of applicable safety measures should follow the internationally accepted priority
ranking of manufacturer safety measures. That is, engineering controls (e.g., filters, shielding,
etc) are the highest priority, followed by administrative measures (such as warnings and
labels, see 5.4) and then personal protective equipment as the last resort. Details should be
provided in application-specific vertical standards.
5 Guidelines for lamp and lamp system manufacturers on how to apply IEC
5.1 Limit values
5.1.1 General
It should be noted that the risk group classification system of IEC 62471 is primarily applied to
lamps. However, in terms of product safety, the lamp system manufacturer has responsibility
for assessing the final lamp system product. Because of different technical tasks and needs,
manufacturers of lamp systems or luminaires might have limited capabilities for tests and

measurements and they commonly rely on the lamp/LED data provided by the lamp/LED
manufacturer. Therefore, guidance is provided on how and when lamp system manufacturers
may rely on data provided by the lamp manufacturer.
There are many types of lamps for which the intended applications are known. For instance,
for conventional light sources, the modifications of the safety-related optical features of the
incorporated lamp by the lamp system manufacturer are generally not significant. In most
cases there is a single conventional lamp type (light bulb) used for a luminaire and the lamp
system manufacturer only adds a fixture and a power supply. In these cases, the lamp data
are usually directly transferable to the lamp system. The assessment and risk group
classification of the lamp can be used by the lamp system manufacturer for classification of
the lamp system. However, other types of lamps may need detailed consideration.
The limit values of the safety standard are provided in two different quantities, which require
separate consideration.
– 12 – 62471-2/TR © IEC:2009(E)

5.1.2 Limits provided in irradiance/radiant exposure

In the spectral ranges 200 nm to 400 nm and 1 400 nm to 3 000 nm where the emission limits

in IEC 62471 are provided in irradiance or radiant exposure, the measurements of a single

lamp can not simply be transferred directly to a lamp system but require an analysis of the

optical additivity to determine the system risk group.

When a lamp is employed with additional integrated or attached modifying or projection

optics, this lamp system should be considered as a different product and the lamp system
manufacturer should provide the new risk group safety classification.

NOTE Additional optics primarily modify the irradiance of a source (i.e. may have a significant impact where the

classification is based on irradiance or radiant exposure-criteria), whereas the radiance may remain unchanged
(i.e. less impact where the classification is based on radiance-criteria).
5.1.3 Limits provided in (time integrated) radiance
In cases where the emission limits in IEC 62471 are provided in terms of spatially averaged
radiance or time-integrated spatially averaged radiance, the principle of conservation of
radiance may be used with caution. That is, if a lamp or single LED emits below the radiance
level specified (per risk group), the final lamp system or LED-array also can not exceed the
accessible emission limits. IEC 62471 requires measurements of spatially averaged radiance
(3.15) values with the consequence that the relationship between the field of view and the
source area, as it was used for the characterisation of a single component, may be changed
by the integration of the single lamp or LED into luminaries (arrays) or with the attachment of
beam-shaping optics.
Under specific conditions (see 5.2.2), the assessment of a single lamp/LED is directly
transferable to the lamp system or luminaire. The risk group will remain the same, or may be
reduced (e.g., by filters, etc.).
NOTE Since additional optics primarily modify (increase) the irradiance of a source rather than the radiance, an
evaluation should verify that the most restrictive classification criterion of the lamp system has not been changed
(from radiance to irradiance criterion).
5.2 Guidelines for lamp/LED manufacturers
5.2.1 General
The primary purpose of lamp risk-group classification by the lamp or LED manufacturer is to
inform the user or final-product manufacturer of potential hazards that may need to be
addressed in the safety design of the final product. Therefore, when a lamp is placed in Risk
Groups 1, 2 or 3, it is important for the user to be informed of which potential hazards may
require controls. If the manufacturer provides the EHV or HD for the lamp (see 5.3.4), the
determination of appropriate controls can be simplified.

5.2.2 Measurement conditions
In the range 200 nm to 400 nm or 1 400 nm to 3 000 nm where the limits in IEC 62471 are
provided in irradiance or radiant exposure, the measurements should be performed according
to IEC 62471.
In cases where the limits in IEC 62471 are provided in spatially averaged radiance or time-
integrated radiance, the source radiance (according to 3.14) data should be determined
(LEDs: operating under maximum operating conditions, such as maximum current) according
to IEC 62471. The angle of acceptance should be 1,7 mrad in any case.
NOTE These values should be compared with the risk group-specific limit values (rather than apply different
angles of acceptance). Under these conditions it can be assured that the risk group allocation of the component in
any case is directly transferable and useful to the characterisation of the final lamp system.

62471-2/TR © IEC:2009(E) – 13 –

If the use of the product is known and unambiguous, the application-specific requirements

(i.e. vertical standards) should be applied, where these exist, or subclauses 4.2 and 4.3

should be applied.
In case of multi-purpose lamps or if application-specific requirements (i.e. vertical standards)

do not exist, the measurement of single lamps and components should be performed at a

distance of 200 mm and the risk group and values should appear in the user information.

The assessment and risk group classification should be based on these values.

5.2.3 User information
The user information should include the risk group classification of the lamp that can be used
for risk group classification of a lamp system.
Information on risk group classification should be given for the intended use. Information
should be provided if application-specific conditions or requirements (as pointed out in 4.2
and 4.3 or as required by vertical standards) were applied. It should be noted that re-
classification may be necessary if the lamp is used in other applications.
In the range 200 nm to 400 nm or 1 400 nm to 3 000 nm where the classification is based on
irradiance or radiant exposure, it should be noted that the assessment of a single lamp can
not be automatically transferred to the final lamp system. However, if the integration of the
lamp into a lamp system does not change the accessible emission characteristics of the lamp,
the risk group classification of the lamp system remains the same as the risk group of the
lamp.
5.3 Guidelines for lamp system/luminaire manufacturers
5.3.1 General
The lamp risk group classification indicates necessary safety measures to reduce the risk
group required for the application as specified in vertical standards. If the risk group of the
lamp is below the maximum appropriate for the application (see Table 3), the manufacturer
should assure that the risk group is directly transferable to the lamp system.
Lamp manufacturers produce some lamp types solely intended for specific applications (4.2
and 4.3, or as required by vertical standards) and these products should be classified by the
lamp manufacturer only under the application-specific conditions, if they exist. If these
sources are modified or marketed for use for other purposes, the lamp system manufacturer
should perform the re-assessment and assign the appropriate risk group.

5.3.2 Sources for general lighting service (GLS)
IEC 62471 states that for lamps and lamp systems used for GLS the hazard values should be
reported as irradiance or spatially averaged radiance values at a distance which produces an
illuminance of 500 lux. Only lamps and lamp systems which are classified as Exempt Group
with respect to the skin hazard when assessed at the location of the 500 lux illuminance level,
should normally be used for GLS applications. In addition, if the application requires skin
access to the optical radiation from the source where the illuminance is likely to exceed
500 lux for periods of exposure longer than 1 h, the user should be warned that an exposure
assessment may be required.
NOTE The above is intended to ensure that applications are considered where, for example, the UV emission
limits may be exceeded. This may be of concern for some lamps where the emission limits are not exceeded at 500
lux, but may be exceeded at a higher illuminance level where the hands, for example, may be located during fine
detail task illumination, or where the head is closer to the source than the surface illuminated at 500 lux.
The required illuminance measurement of the GLS lamp systems takes into account
contributions from all the elements of the lamp system. In contrast to the radiance

– 14 – 62471-2/TR © IEC:2009(E)

measurement for risk group determination, the acceptance angle for the illuminance

measurement of GLS sources is not limited. When multiple lamps or modifying optics are

applied to a GLS product, the ultraviolet and infrared emission of the product in many cases

may be reduced; thus, the corresponding risk is reduced. Furthermore, if lenses or arrays

increase the 500 lux distance, the angular subtense of the component sources decrease (and

the spatially averaged radiance decreases), so that the risk remains essentially the same.

In cases where the classification by the lamp manufacturer is based on radiance or time-

integrated radiance and where irradiance-dependant hazards can be neglected (LEDs or by

the use of appropriate filters), the GLS-classification of the lamp can directly be transferred to
the lamp system/luminaire.
5.3.3 Multi-purpose lamps
The following general approach should be followed in the course of risk group determination
of lamp systems. In cases where the risk classification of the lamp is based on the most
restrictive radiance or time-integrated radiance criteria, these values remain unchanged or are
decreased by integration of the lamp into a system or by adding optical elements. Such
measures or elements, in contrast, may change the irradiance or radiant exposure produced
by a source and should be considered in cases where the risk grouping of the incorporated
lamp is based on those criteria. However, the possible variation of the most restrictive
classification criterion, i.e. from radiance to irradiance, should be considered in case of
radiance-based classification of the incorporated lamp.
5.3.4 Determination of the hazard distance
In order to be independent of the use condition, the risk group classification of lamps and
lamp systems is based on worst case assumptions of exposure duration, pupil size and
viewing distance. However, the emission of lamps is often divergent and the viewer-related
risk at a reasonable distance may not be adequately reflected by the risk classification of the
equipment, i.e. the real risk is lower.
The exposure hazard values (EHV), i.e. the excess over the applicable exposure limits, have
significant practical relevance (see 3.2). This concept can be helpful when considering
appropriate control measures: to limit either the exposure duration or the accessibility of a
source as applicable.
The EHV may be graphically presented as distance-dependent values: with increasing
distance from a lamp or lamp system the applicable hazard values decrease - see Figure 1. At
the distance X , EHV = 1, i.e. the EHV equals the applicable emission limit value. Distance X
1 1
is the hazard distance (HD) for this lamp system. At distance X , the optical radiation hazard
value exceeds the applicable emission limit value by a factor of A. At this distance, excessive
exposure to optical radiation may be reduced either by restricting exposure time by a factor of

A (if the emission limit values are expressed in terms of radiant exposure or time integrated
radiance), or by using engineering controls (such as filters) which attenuate the accessible
emission and/or personal protective means (such as eyewear, clothing) which would limit the
potential exposure to the emitted energy.

62471-2/TR © IEC:2009(E) – 15 –

Optical hazard value exceeds applicable ELV by

factor of A: reduce exposure duration by factor of

A or attenuate emission by factor of A

A
Optical hazard value = ELV
Distance X : EHV = A
Distance X : EHV = 1
0,1
X X
2 1
Distance IEC  1578/09
Figure 1 – Example of graphic presentation of distant dependent
emission hazard values
Similar to the risk group allocation of the lamp or lamp system, these hazard distance values
can also be categorized in order to determine the effective viewer-related risk (3.19) under
realistic use conditions. For instance, with increasing distance from a Risk Group 3 lamp
system (as categorised at a measurement distance of 200 mm) the risk for the viewer
stepwise decreases from Risk Group 2 (e.g. at X in Figure 1) to Risk Group 1 and to Exempt
(e.g. at X in Figure 1), at the distances where the irradiance, or from where the measured
radiance, falls below the applicable risk-group-specific emission limit.
Therefore, in addition to assigning a lamp system to a risk group, the lamp system
manufacturer should also provide such data. Where the lamp system is assigned to a risk
group above Exempt, the manufacturer should, at least, provide the hazard distance (HD)
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