oSIST prEN 16163:2023

Conservation of Cultural Heritage - Guidelines and procedures for choosing appropriate lighting for indoor exhibitions

This European standard defines the procedures as well as the means to implement adequate lighting, with regard to the exhibition lighting and the conservation policy. This also includes security and cleaning lighting. It takes visual, exhibition and conservation aspects into account and it also discusses the implications of the lighting design on the safeguarding of cultural heritage. This document gives recommendations on luminous exposure values. It aims to provide a tool for setting up a common European policy and a guide to help curators, conservators and project managers to assess the correct lighting that can ensure the safeguarding of the objects. This European standard covers indoor lighting for heritage objects on exhibition in both public and private sites and does not consider lighting in other cultural heritage contexts such as open-air collections, etc.
This document does not cover back of house activities such as conservation-restoration, storage, emergency lighting and research.

Erhaltung des kulturellen Erbes - Leitlinien und Verfahren für die Auswahl geeigneter Beleuchtung für Innenausstellungen

Dieses Dokument legt die Verfahrensweisen und Hilfsmittel zur Umsetzung einer bezüglich der Ausstellungs-beleuchtung und der Erhaltungsstrategie angemessenen Beleuchtung fest. Dies schließt auch Sicherheits- und Reinigungsbeleuchtung ein. Dabei werden visuelle Aspekte, Ausstellungs- und Erhaltungsaspekte berücksichtigt, und die Auswirkungen der Beleuchtungsgestaltung auf die Bewahrung des kulturellen Erbes werden ebenfalls erörtert. Dieses Dokument gibt Empfehlungen für Belichtungswerte. Ziel ist die Bereitstellung eines Instrumentes für die Aufstellung gemeinsamer europäischer Grundsätze und einer Anleitung, die Kuratoren, Konservatoren und Projektleitern dabei hilft, die richtige Beleuchtung festzulegen, die den Schutz der Objekte sicherstellen kann. Dieses Dokument behandelt die Innenraumbeleuchtung von Objekten des kulturellen Erbes sowohl in öffentlichen als auch privaten Ausstellungsstätten, wobei Beleuch-tungen in anderen Zusammenhängen von kulturellem Erbe, wie beispielsweise Ausstellungen unter freiem Himmel usw., nicht berücksichtigt werden.
Dieses Dokument deckt keine Tätigkeiten außerhalb der Ausstellungsräume ab, wie beispielsweise Konservierung-Restaurierung, Lagerung, Notbeleuchtung und Forschung.

Conservation du patrimoine culturel - Lignes directrices et procédures concernant le choix d'un éclairage adapté pour les expositions en intérieur

Le présent document définit les procédures ainsi que les méthodes de mise en oeuvre d'un éclairage adapté, en matière d'éclairage d'exposition et de politique de conservation. Ceci inclut également l'éclairage de sécurité et de nettoyage. Il tient compte des paramètres de vision, d'exposition et de conservation, et traite également des répercussions de la conception de l'éclairage sur la sauvegarde du patrimoine culturel. Le présent document fournit des recommandations relatives aux valeurs de dose d'exposition. Son objectif est de fournir un outil pour élaborer une politique européenne commune, et un guide pour aider les conservateurs, les conservateurs-restaurateurs et les chargés de projet à évaluer l'éclairage idéal à même d'assurer la sauvegarde des biens. Le présent document traite de l'éclairage intérieur dans le cadre de l'exposition de biens culturels sur des sites publics et privés, mais ne couvre pas l'éclairage dans d'autres contextes de patrimoine culturel, tels que les collections en plein air, etc.
Le présent document ne traite pas des activités d'arrière-plan telles que la conservation-restauration, le stockage, l'éclairage de secours et la recherche.

Ohranjanje kulturne dediščine - Smernice in postopki za izbiro ustrezne razsvetljave za razstave v zaprtih prostorih

General Information

• Status: Not Published
• Public Enquiry End Date: 11-Apr-2023
• ICS: 91.160.10 - Interior lighting
• ICS: 97.195 - Items of art and handicrafts. Cultural property and heritage
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 24-Jan-2023
• Due Date: 13-Jun-2023
• Completion Date: 12-Apr-2023
• Ref Project: prEN 16163 - Conservation of Cultural Heritage - Guidelines and procedures for choosing appropriate lighting for indoor exhibitions

Relations

• Replaces: SIST-TS CEN/TS 16163:2014 - Conservation of Cultural Heritage - Guidelines and procedures for choosing appropriate lighting for indoor exhibitions
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 16163:2023
01-marec-2023
Nadomešča:
SIST-TS CEN/TS 16163:2014
Ohranjanje kulturne dediščine - Smernice in postopki za izbiro ustrezne
razsvetljave za razstave v zaprtih prostorih
Conservation of Cultural Heritage - Guidelines and procedures for choosing appropriate
lighting for indoor exhibitions
Erhaltung des kulturellen Erbes - Leitlinien und Verfahren für die Auswahl geeigneter
Beleuchtung für Innenausstellungen
Conservation du patrimoine culturel - Lignes directrices et procédures concernant le
choix d'un éclairage adapté pour les expositions en intérieur
Ta slovenski standard je istoveten z: prEN 16163
ICS:
91.160.10 Notranja razsvetljava Interior lighting
97.195 Umetniški in obrtniški izdelki. Items of art and handicrafts.
Kulturne dobrine in kulturna Cultural property and
dediščina heritage
oSIST prEN 16163:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 16163:2023

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oSIST prEN 16163:2023


DRAFT
EUROPEAN STANDARD
prEN 16163
NORME EUROPÉENNE

EUROPÄISCHE NORM

January 2023
ICS 97.195 Will supersede CEN/TS 16163:2014
English Version

Conservation of Cultural Heritage - Guidelines and
procedures for choosing appropriate lighting for indoor
exhibitions
Conservation du patrimoine culturel - Lignes Erhaltung des kulturellen Erbes - Leitlinien und
directrices et procédures concernant le choix d'un Verfahren für die Auswahl geeigneter Beleuchtung für
éclairage adapté pour les expositions en intérieur Innenausstellungen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 346.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.

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.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 16163:2023 E
worldwide for CEN national Members.

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prEN 16163:2023 (E)
Contents Page
European foreword . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Symbols . 15
5 Visual needs of visitors . 15
5.1 General . 15
5.2 Visibility of details and contrasts . 16
5.3 Colour discrimination . 18
5.4 Glare . 19
5.5 Reflections . 20
6 Sensitivity of cultural property to light . 20
6.1 General . 20
6.2 Mechanisms of damage . 20
6.3 Sensitivity and classification for cultural property . 22
7 Finding a compromise between visitor needs and conservation requirements . 23
7.1 General . 23
7.2 Limitations for total luminous exposure . 23
8 Measurements . 25
8.1 Measurement of illuminance . 25
8.2 Measurement of UV radiation . 25
9 Exhibition lighting . 26
9.1 General . 26
9.2 Typology of lighting design. 26
9.3 Simulation and mock-ups. 27
10 Lighting control. 28
10.1 General . 28
10.2 Energy efficiency . 28
11 Maintenance and monitoring of correct lighting conditions . 29
11.1 Actions to be taken before setting-up a lighting project . 29
11.2 Maintenance and control actions to undertake over the long term . 30
12 Security and cleaning . 31
Annex A (informative) Characteristics of light sources . 32
Annex B (informative) Glasses and films characteristics . 38
Annex C (informative) Filters . 39
Annex D (informative) Additional methods for the evaluation and limitation of
photochemical damage for different light sources . 40
Annex E (informative) Light sources and lighting attachments . 43
Annex F (informative) Colour rendering index, fidelity index and gamut index . 44
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Annex G (informative) Relative spectral sensitivities Y of photochemically sensitive
surfaces versus wavelength X of incoming radiation . 47
Annex H (informative) Facility report . 49
Annex I (informative) Good practices for exhibition lighting . 50
Annex J (informative) Lighting management protocols . 54

3

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oSIST prEN 16163:2023
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European foreword
This document (prEN 16163:2023) has been prepared by Technical Committee CEN/TC 346
“Conservation of Cultural Heritage”, the secretariat of which is held by UNI.
This document is currently submitted to the CEN Enquiry.
This document will supersede CEN/TS 16163:2014.
prEN 16163:2023 includes the following significant technical changes with respect to
CEN/TS 16163:2014:
since the publication of the CEN/TS 16163 in 2014, the technology of lighting has evolved considerably
and an update of the content has proven to be necessary. In addition to taking into account
technological advances and new calculation methods in the field of lighting in recent years, the present
version of prEN 16163 contains the elements of good practices for the exhibition lighting design, in its
subjective form, as an element of museography, which had not found its place in the previous version.
4

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oSIST prEN 16163:2023
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Introduction
Lighting is needed for many specific functions in museums and other cultural heritage buildings, such as
research, conservation and permanent or temporary exhibitions. Lighting is one of the most important
factors enabling visitors to fully enjoy works of art and other cultural property. In fact, lighting is a key
medium in which visitors interpret and appreciate cultural heritage. Light is needed to see well but this
may present a challenge when what is being viewed will deteriorate in the presence of light. When
displaying exhibits as a part of Cultural Heritage, it is essential to consider a controlled use of light, to
preserve them for the future generations. Indeed, light is an environmental factor, which is a threat to
many objects. Alone or in combination with other environmental factors (temperature, humidity,
pollution, etc.) light causes fading, discoloration and embrittlement of a wide range of materials. This
damage is cumulative and irreversible: no conservation treatment can restore original appearance of
colours and the material characteristics. Therefore, the challenge of museum exhibition lighting is to
find an appropriate compromise between the long term preservation of the object and the needs of
visitors to view them within a suitable exhibition design. As an integral part of exhibition lighting, the
following aspects should be considered, mentioned below without priority:
— the conservation aspect, related to the sensitivity of the exhibit at different wavelengths of the
incident radiant energy, the spectral composition of the light source and the total luminous
exposure,
— the visual aspect, related to the impact of lighting on the visitor experience: lighting has to allow
visitors to see exhibits on display, with the correct colour perceptions without glare, reflections or
insufficient illumination.
— the design aspect related to the concept and position of the exhibition architecture, the point of
view of the curator and all others involved in the purpose and/or didactic objectives of the
exhibition.
This document uses terms defined in European and International (CIE International lighting
vocabulary) terminology standards, but their definitions have been adapted to the intended users of
this specification.
5

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1 Scope
This document defines the procedures as well as the means to implement adequate lighting, with regard
to the exhibition lighting and the conservation policy. This also includes security and cleaning lighting.
It takes visual, exhibition and conservation aspects into account and it also discusses the implications of
the lighting design on the safeguarding of cultural heritage. This document gives recommendations on
luminous exposure values. It aims to provide a tool for setting up a common European policy and a
guide to help curators, conservators and project managers to assess the correct lighting that can ensure
the safeguarding of the objects. This document covers indoor lighting for heritage objects on exhibition
in both public and private sites and does not consider lighting in other cultural heritage contexts such
as open-air collections, etc.
This document does not cover back of house activities such as conservation-restoration, storage,
emergency lighting and research.
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.
EN 13032-1:2004+A1:2012, Light and lighting - Measurement and presentation of photometric data of
lamps and luminaires - Part 1: Measurement and file format
prEN 15999-1, Conservation of cultural heritage — Guidelines for design of showcases for exhibition and
preservation of objects — Part 1: General requirements
prEN 15999-2, Conservation of cultural heritage – Guidelines for design of showcases for exhibition and
preservation of objects – Part 2: Technical aspects
ISO/CIE 19476:2014, Characterization of the performance of illuminance meters and luminance meters
3 Terms and definitions
For the purposes of this document, the following terms and definitions and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
IEC Electropedia: available at http://www.electropedia.org/
ISO Online browsing platform: available at http://www.iso.org/obp
3.1
accent lighting
directional lighting to emphasize a particular exhibit (3.18) or to draw attention to a spot in the field of
vision
[SOURCE: CIE S 017/E:2020, modified]
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3.2
annual luminous exposure
−1
total luminous exposure (3.45) per year (unit: lux hours per years, lx · a )
Note 1 to entry: One year of museum display is approximately 3 000 h. See also 3.34.
3.3
blue wool test: test for light fastness
certified set of eight pieces of wool each dyed with a different specific blue dye graded to fade after a set
exposure to light (3.24)
[SOURCE: ISO 105-B08:1995]
Note 1 to entry: This system is usually referred to as the Blue Wool Standard (BWS) and it is used in museums
to assess the radiation exposure of materials. The eight wool pieces are numbered #1 to #8, each about 2 to 3
times as sensitive as the next. High sensitivity is defined as materials rated #1, #2, or #3; medium as #4, #5, or #6;
and low as #7, #8. A panel of selected blue wool samples is left at the measurement point and after a period of
time it can be seen which samples have faded and the dose of light (3.24) received approximated.
3.4
colour rendering

effect of an illuminant on the perceived colour of exhibits (3.18) by conscious or subconscious
comparison with their perceived colour under a reference illuminant
[SOURCE: CIE S 017/E:2011, modified]
3.5
colour rendering index
R
a
derived from the colour rendering (3.4) indices for a specified set of 8 test colour samples
Note 1 to entry: see Annex F Colour rendering index, fidelity index and gamut index.
3.6
colour fidelity index
R
f
derived from the colour fidelity indices for a specified set of 99 test colour samples
Note 1 to entry: see Annex F Colour rendering index, fidelity index and gamut index.
Note 2 to entry: see CIE 224:2017 for further information.
3.7
gamut index
R
g
the R gamut index provides information about the relative range of colours that can be produced by a
g
white light source (3.25). A score close to 100 indicates that, on average, the light source (3.25)
reproduces colours with similar levels of saturation as a reference source of the same correlated colour
temperature (3.9)
Note 1 to entry: see Annex F Colour rendering index, fidelity index and gamut index index.
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3.8
colour temperature
T
c
temperature of a Planckian radiator whose radiation has the same chromaticity as that of a given
stimulus (unit: K)
[SOURCE: CIE S 017/E:2020, modified – 3 notes deleted]
3.9
correlated colour temperature
CCT
temperature of the Planckian radiator whose perceived colour most closely resembles that of a given
stimulus at the same brightness and under specified viewing conditions (unit: K)
Note 1 to entry: Based on EN 12665 and modified for specific use.
3.10
cultural heritage
tangible and intangible entities of significance to present and future generations
Note 1 to entry: The term “object” (3.34) is used in this standard for cultural heritage. In specific professional
contexts, other terms are used: e.g. “artefact”, “cultural property”, “item”.
[SOURCE: EN 15898:2019, modified: note 1 to entry added]
3.11
damage potential
P
dm
ratio of effective damaging irradiance E (3.17) and the illuminance E (3.21) at a point on the surface
dm
for a specific light source (3.25) (unit: W/lm)
3.12
daylight
part of global solar radiation capable of causing a visual sensation
Note 1 to entry: When dealing with actinic effects of optical radiation, this term is commonly used for radiations
extending beyond the visible region of the spectrum.
[SOURCE: CIE ILV:2020, 17-29-105 modified: Note 1 to entry added]
3.13
daylighting
lighting for which daylight (3.12) is the light source (3.25)
Note 1 to entry: it means that window or other devices are taken into consideration
[SOURCE: CIE S 017/E:2011 modified: original Note 1 to entry deleted]
3.14
daylight factor
D
ratio of the illuminance (3.21) at a point on a given plane due to the light (3.24) received directly or
indirectly from a sky of assumed or known luminance (3.31) distribution, to the illuminance (3.21) on a
horizontal plane due to an unobstructed hemisphere of this sky, excluding the contribution of direct
sunlight to both illuminances (3.21)
[SOURCE: EN 12665:2018]
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3.15
diversity
extreme uniformity (syn.)
Ud
ratio of minimum illuminance (3.21) (luminance (3.31)) to maximum illuminance (3.21) (luminance
(3.31)) on (of) a surface
Note 1 to entry: Diversity has unit one.
[SOURCE: EN 12665, Note 1 and SOURCE modified]
3.16
dosimeter
indicator revealing the effects of total irradiant exposure during a given time
Note 1 to entry: The above definition is valid in the context of the present European standard and concerns
lighting field only.
3.17
effective damaging irradiance
E
dm
part of the irradiance (3.23) causing damaging photochemical reaction. It takes account of the spectrum
of the incident radiation and the spectral response of the receiving material (unit: watt per square
-2
metre, W m )
Note 1 to entry:
E = ∫ Ε s (λ) dλ
dm e,λ dem,rel
where
Ε is the total irradiance (3.23) at a specified wavelength and s (λ) is the spectral responsivity value of an
e,λ dem,rel
material at a specified wavelength.
3.18
exhibit
item shown in the exhibition (3.19)
3.19
exhibition
designed display of exhibit(s) (3.18) and information
3.20
filter
any device that modifies or reduces a portion of the electromagnetic spectrum
Note 1 to entry: more information is included in Annex C of the present document.
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3.21
illuminance

E
quotient of the luminous flux (3.32) dΦ incident on an element of the surface containing the point, to the
−2
area dΑ of that element (unit: lux, lx = lm⋅m )
Note 1 to entry: It represents the quantity of light (3.24) impinging on a surface.
[SOURCE: CIE S017:2020, modified: Note 1 to entry added]
3.22
infrared radiation
IR
optical radiation for which the wavelengths are longer than those for visible radiation
Note 1 to entry: For infrared radiation, the range between 780 nm and 1 mm is commonly subdivided into:
IR-A: 780 nm to 1400 nm, or 0,78 µm to 1,4 µm;
IR-B: 1,4 µm to 3,0 µm;
IR-C: 3 µm to 1 mm.
Note 2 to entry: A precise border between “visible” and “infrared” cannot be defined, because visual sensation
at wavelengths greater than 780 nm is noted for very bright sources (3.43) at longer wavelengths.
Note 3 to entry: In some applications the infrared spectrum has also been divided into “near”, “middle” and
“far” infrared; however, the borders necessarily vary with the application.
[SOURCE: CIE S 017/2020, 17-21-004]
3.23
irradiance
E
e
radiometric quantity (3.37); the radiant flux (3.36) per unit area at a point on the surface (unit: watt per
-2
square metre, W m )
3.24
light
1. characteristic of all sensations and perceptions that is specific to vision
2. radiation that is considered from the point of view of its ability to excite the human visual system
Note 1 to entry: This term has 2 meanings that should be clearly distinguished. When necessary to avoid
confusion between these 2 meanings the term “perceived light” may be used in the first sense.
Note 2 to entry: Light is normally, but not always, perceived as a result of the action of a light stimulus on the
visual system.
Note 3 to entry: The term “light” is sometimes used for optical radiation extending outside the visible range, but
this usage is not recommended.
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3.25
light source
surface or object (3.34) emitting light (3.24)
Note 1 to entry: A light source can be self-emitting (primary light source) or non-self-emitting (secondary light
source).
[SOURCE: CIE S017:2020]
3.26
lighting design
result of the lighting designer (3.27) proposal
3.27
lighting designer
professional with suitable education and relevant experience in lighting design (3.26), able to manage
the aesthetic, behavioural and technical issues of the project
3.28
lighting management
all actions that contribute to the control and organisation of light (3.24)
3.29
lighting management protocol
language that allows different lighting devices to communicate
3.30
luminaire
apparatus which distributes, filters (3.20) or transforms the light (3.24) emitted from one or more light
sources (3.25) and which includes, all the parts necessary for fixing and protecting the light sources
(3.25) and, where necessary, circuit auxiliaries together with the means for connecting them to the
electric supply
3.31
luminance
L
2
light (3.24) reflected or emitted by a surface in the direction of the observer’s eyes (unit: candela/m
2
(cd/m ))
Note 1 to entry: Based on EN 12665 and modified for specific use.
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3.32
luminous flux
Φ
luminous power emitted by a light source (3.25), photometric quantity (3.35) derived from the
radiometric quantity (3.37) radiant flux (3.36) (radiant power) by evaluating the radiation according to
the spectral sensitivity of the human eye (as defined by the CIE standard photometric observer) (unit:
lumen, lm)
Note 1 to entry: For the practical use of this document, in this definition, the values used for the spectral
sensitivity of the CIE standard photometric observer are those of the spectral luminous efficiency function V(λ)
(photopic vision).
Note 2 to entry: See CIE S 017/E:2011 or IEC-IEV, 1987, 845-01-22 for the definition of spectral luminous
efficiency, 845-01-23 for the definition of the CIE standard photometric observer and 845-01-56 for the definition
of luminous efficacy of radiation and ISO 23539:2005(E)/CIE S 010/E:2004.
Note 3 to entry: Based on EN 12665 and modified for specific use.
3.33
luminous intensity
I
density of luminous flux (3.32) with respect to solid angle in a specified direction (unit: candela, cd = lm
−1
sr ; sr = steradian)
Note 1 to entry: It is the luminous flux (3.32) on a small surface, divided by the solid angle that the surface
subtends at the source (3.43) (CIE S 017/E:2011 or IEC-IEV, 1987, 845-01-31).
Note 2 to entry: The candela is the base SI photometric unit. For its definition, see CIE S 17/E:2011 or IEC-IEV,
1987, 845-01-050 or the BIPM SI Brochure.
Note 3 to entry: Based on EN 12665 and modified for specific use.
3.34
object
single manifestation of tangible cultural heritage (3.10)
Note 1 to entry: The term “object” (3.34) is used in this standard for cultural heritage (3.10), both immovable and
movable. In specific professional contexts, other terms are used: e.g. “artefact”, “cultural property”, “item”, “site”,
“building”, “monument”, “specimen”, “structure”, “cultural landscape”, “document”.
[SOURCE: EN 15898:2019, 3.13]
3.35
photometric quantity
quantity that is based on the perception of radiation by the human eye and is valid only for visible
radiation
3.36
radiant flux
Φ
e
all radiation emitted in all directions from a light source (3.25) (unit: watt, W)
3.37
radiometric quantity
quantity that is physically related to the electromagnetic radiation
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3.38
reflectance
ρ
ratio of the (luminous or radiant) flux reflected from a surface to the flux incident on it
Note 1 to entry: Based on EN 12665 and modified for specific use.
3.39
reflection
process by which radiation is returned by a surface or a medium, without change of frequency of its
monochromatic components
Note 1 to entry: Part of the radiation falling on a medium is reflected at the surface of the medium (“surface
reflection”); another part may be scattered back from the interior of the medium (“volume reflection”).
[SOURCE: CIE S 017/E:2011 17-1065 – modified, note 2 to entry deleted]
3.40
relative damage potential
RDP
ratio of the damage potential (3.11) of a specific light source (3.25) and the damage potential (3.11) of
the CIE standard illuminant A (2 856 K) (equivalent to the incandescent lamp); it is dimensionless
3.41
relative spectral responsivity
relative damage action spectrum (syn.)
s(λ)
dm,rel
describes the wavelength dependence of the photochemical damage properties of a material, such as
fading; it is dimensionless. The suffix stands for damaging
dm
1
sfλ α λ⋅⋅ λ
( ) ( ) ( )
dm,rel
λ
where

is the spectral absorbance

αλ( )
is a function of wavelength determined by the receiving material

f(λ)
Note 1 to entry: For many non-pigmented materials and for exhibits (3.18) whose spectral absorption behaviour is
-b (λ[nm]/ −300)
not known or available s(λ)dm,rel can be approximated by the exponential function e In this case the
function is normalized at 300 nm so that s(λ) = 1 for λ = 300 nm.
dm,rel
[SOURCE: based upon CIE 157:2004]
3.42
relative UV content
ratio of the amount of UV radiation that a surface receives to the amount of visible radiation (lumens)
from the same light source (3.25) (units: µW/lm)
Note 1 to entry: there is no standardized method on how to measure and / or calculate it.
13
=

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oSIST prEN 16163:2023
prEN 16163:2023 (E)
3.43
sensitive objects
exhibits (3.18), which can be more or less affected by electromagnetic radiations and/or other
environmental facto
...