1、BRITISH STANDARD BS EN 13721:2004 Furniture Assessment of the surface reflectance The European Standard EN 13721:2004 has the status of a British Standard ICS 97.140 BS EN 13721:2004 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 20 Septembe
2、r 2004 BSI 20 September 2004 ISBN 0 580 44464 3 National foreword This British Standard is the official English language version of EN 13721:2004. The UK participation in its preparation was entrusted to Technical Committee FW/1, Common test methods for furniture, which has the responsibility to: A
3、list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Stan
4、dards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standar
5、d does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments a
6、nd promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 9 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No.
7、 Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN13721 July2004 ICS97.140 Englishversion FurnitureAssessmentofthesurfacereflectance MeublesEvaluationdelaluminancelumineusedes surfaces MbelBewertungdesOberflchenreflexionsgrades ThisEuropeanStandardwasapprovedbyCENon13May2004. CENmembers
8、areboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheCentralSecretariatortoanyCENmember.
9、 ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheCentralSecretariathasthesamestatusast heofficial versions. CENmembersarethenationalstandardsbodiesofAustria,Belgi
10、um,Cyprus,CzechRepublic,Denmark,Estonia,Finland,France, Germany,Greece,Hungary,Iceland,Ireland,Italy,Latvia,Lithuania,Luxembourg,Malta,Netherlands,Norway,Poland,Portugal, Slovakia, Slovenia,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EURO
11、PISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2004CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN13721:2004:EEN 13721:2004 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Princi
12、ple5 5 Viewing/illumination condition geometry .5 6 Standard colorimetric observer and standard illuminant6 7 Equipment 6 8 Preparation and conditioning of test units/test panels .7 9 Instrument calibration .7 9.1 Calibration 7 9.2 Reference scale7 9.3 Reference standards (primary and working) 7 10
13、Test Procedure.7 11 Test report 8 Bibliography 9 EN 13721:2004 (E) 3 Foreword This document (EN 13721:2004) has been prepared by Technical Committee CEN/TC 207 “Furniture”, the secretariat of which is held by UNI. This European Standard shall be given the status of a national standard, either by pub
14、lication of an identical text or by endorsement, at the latest by January 2005, and conflicting national standards shall be withdrawn at the latest by January 2005. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to impleme
15、nt this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. E
16、N 13721:2004 (E) 4 1 Scope This document specifies a method for the assessment of the surface reflectance of furniture surfaces and relates to rigid surfaces of all finished products regardless of materials, except for finishes on leather and fabrics, which are excluded from this document. The test
17、is intended to be carried out on finished furniture, but can be carried out on test panels of the same material, finished in an identical manner to the finished product, and of a size sufficient to meet the requirements of the test. The test method does not apply to extreme reflectances, i.e. below
18、15 % and above 75 %, because in the extreme reflectance range the results of the different measurement methods could deviate. It is not applicable to some metallic paints and pearly coatings. 2 Normative references The following referenced documents are indispensable for the application of this docu
19、ment. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 7724-1:1984, Paints and varnishes - Colorimetry Part 1: Principles ISO 7724-2, Paints and varnishes Colorimetry - Part 2: Colour m
20、easurement CIE 1931, Standard colorimetric colour coordinates CIE 1964, Colorimetry, CIE Standard Recommendations 3 Terms and definitions For the purposes of this document the following terms and definitions apply. 3.1 reflectance ratio of the radiant flux reflected in the directions within a given
21、cone to that reflected in the same directions by a perfect reflecting diffuser identically irradiated in the observed wavelength interval (called spectral reflectance factor R () in ISO 7724-1:1984) 3.2 trichromatic compound or lightness factor, Y value given by the equation in clause 10 of this doc
22、ument 3.3 test unit finished item of furniture 3.4 test surface part of the test unit, where the test area is included EN 13721:2004 (E) 5 3.5 test panel panel produced in the same way as the test surface; it shall be used when it is not possible to carry out the test directly on the test surface 3.
23、6 test area area under the equipment, where the measurement is carried out 3.7 pearly coatings coating with pearly additives. The pearly additives act like microscopy mirrors reflecting and transferring the light in several directions 4 Principle This standard is based on the reflectance measurement
24、 or on the related value, measured as the trichromatic compound or lightness factor, Y. The reflectance of the test unit/test panel shall be measured by a photometric equipment, capable of illuminating the test area by a standardised illuminant and at a standardised angle of incidence. The response
25、is received by a standardised observer. The lightness or trichromatic compound is calculated according to the equation given in clause 10 of this document. 5 Viewing/illumination condition geometry The geometry of measurement illumination/viewing shall be 45/0 or d/8. NOTE For textured surfaces, a 4
26、5/0 geometry is preferable. The denomination of the measurement conditions of the different geometries, are as in the following table (Table 4 of ISO 7724-1:1984). EN 13721:2004 (E) 6 Table 1 Denomination of the measurement conditions of the different geometries Spectral radiometric characteristics
27、Measurement conditions Symbol Illumination Viewing Designation (Abbreviation) R 45/0 ( ) directional 45 5 directional 0 10 45 / normal (45/0) R 0/45 ( )directional* 0 10 directional 45 5 normal/45 (0/45) R d/8 ( )diffuse, integrating sphere directional* 8 2 diffuse / 8 (d/8) Spectral reflectance fac
28、tor R (d) d/8 ( )diffuse, integrating sphere with gloss trap directional* 8 2 diffuse / 8 (d/8) specular reflection excluded Spectral reflectance 8/d ( )directional* 8 2 diffuse, integrating sphere 8 / diffuse (8/d) Spectral diffuse reflectance (d) 8/d ( )directional* 8 2 diffuse, integrating sphere
29、 with gloss trap 8 / diffuse (8/d) specular reflection excluded * The possibility of interreflections between a high gloss specimen and the illuminating optics should be considered. * This is contrary to the recommendations of the CIE (see CIE Publication No. 15) which permits the illumination or th
30、e viewing normal to the specimen (measurement conditions 0/d and d/0). The illumination or observation angle with a small defined deviation from zero as specified in ISO 7724-1 prevents interreflections between the specimen and the illumination or viewing optics when measuring high gloss specimens.
31、6 Standard colorimetric observer and standard illuminant If geometry 45/0 is used, the CIE 1931 supplementary standard colorimetric observer and standard illuminant D65, as defined in ISO 7724-2, shall be used. If geometry d/8 is used, the CIE 1964 supplementary standard colorimetric observer and St
32、andard Illuminant D65, as defined in ISO 7724-2, shall be used. 7 Equipment For the tests, the following equipment may be used: Spectrophotometer as described in ISO 7724-2, or Tristimulus colorimeter as described in ISO 7724-2, or Abridged spectrophotometer as described in ISO 7724-2 EN 13721:2004
33、(E) 7 8 Preparation and conditioning of test units/test panels The test unit/test panel shall be stored for not less than four weeks at a temperature not less than 15 C and not more than 30 C with free access of air. The test unit/test panel shall be kept in a room without direct light exposure. Con
34、ditioning shall begin one week before testing and shall be carried out in air at a temperature of (23 2) C and a relative humidity of (50 + 5) %. The conditioning can be a part of the four weeks above. The test surface shall be cleaned with a soft, clean, lint-free cloth before the test. The test su
35、rface shall be substantially flat, and of sufficient size to take the measurements. 9 Instrument calibration 9.1 Calibration Before carrying out any tests, calibrate the equipment according to ISO 7724-2 or the instructions of the equipment manufacturers. Calibration shall be carried out at the star
36、t of every period of operation and at intervals short enough to maintain equipment accuracy according to the manufacturers instructions. 9.2 Reference scale The reflectance scale, as recommended by the CIE, of the test surface, shall be in accordance with the perfect reflecting diffuser. The spectra
37、l reflectance of the perfect reflecting diffuser is unity for all wavelengths. 9.3 Reference standards (primary and working) The reference standards (primary and working), shall be according to ISO 7724-2. 10 Test Procedure The equipment shall be operated in accordance with the manufacturers instruc
38、tions. After calibrating the equipment measure the value of the tricromatic compound or lightness factor, Y. Y is the integrand of the supplementary spectral luminance efficiency function y () (which emulates the response of the human eye to light for fields of angular subtense more than 4), with th
39、e light reflected from a surface I () R (). The value of Y is standardised so that where the surface is a perfectly reflecting diffuser (perfect white), it would be 100 %, and where the surface reflects no light (perfect black), it would be 0 %. The value of Y is calculated using the following formu
40、la: % 100 ) ( ) ( I ) ( y ) ( ) ( R ) ( I ) ( y Y = Where: y (): luminance efficiency function (given in Table 1 of ISO 7724-1:1984 for every wave length) EN 13721:2004 (E) 8 I (): relative distribution of the energy spectrum for standardised illuminants R (): reflectance Measurements on one surface
41、 shall be taken at three different points, with three measurements at each point. The mean value of the nine measurements shall be calculated. If the spread of the nine single values exceeds 20 % of the mean value, the measurement shall be considered invalid and the procedure shall be repeated using
42、 three different points of the test surface. If the test result fails again, the lightness factor cannot be assessed. 11 Test report The test report shall include at least the following information: a) reference to this document; b) unit or panel tested, including relevant data (wherever possible th
43、e substrate, the finishing system and the finishing date shall be identified); c) arithmetic mean value of the nine measurements including the minimum and maximum values of Y; d) type of instrument, the geometry used and the illuminant (see Clause 7); e) observer (2 or 10); f) specular measurement i
44、ncluding or excluding gloss; g) any deviations from this document ; h) name and address of the test facility; i) date of test. EN 13721:2004 (E) 9 Bibliography 1 Publication VIE 17.4 1984 (4 thversion)International vocabulary for lighting (co-published by CIE and CEI) BS EN 13721:2004 BSI 389 Chiswi
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