1、December 2010 Translation by DIN-Sprachendienst.English price group 9No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).IC
2、S 97.195!$lUE“1735034www.din.deDDIN EN 15886Conservation of cultural property Test methods Colour measurement of surfacesEnglish translation of DIN EN 15886:2010-12Erhaltung des kulturellen Erbes Prfmethoden Farbmessung von matten OberflchenEnglische bersetzung von DIN EN 15886:2010-12Conservation d
3、es biens culturels Mthode dessai Mesurage chromatique des surfacesTraduction anglaise de DIN EN 15886:2010-12www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.1312.10sDIN EN 15886:2010-12 A comma is used as the decimal marker. Nation
4、al foreword This standard has been prepared by Technical Committee CEN/TC 346 “Conservation of cultural property” (Secretariat: UNI, Italy). The responsible German body involved in its preparation was the Normenausschuss Bauwesen (Building and Civil Engineering Standards Committee), Working Committe
5、e NA 005-01-36 AA Erhaltung des kulturellen Erbes. 2 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 15886 September 2010 ICS 97.195 English Version Conservation of cultural property Test methods Colour measurement of surfaces Conservation des biens culturels Mthodes dessai Mesurage chromatique
6、 des surfaces Erhaltung des kulturellen Erbes Prfmethoden Farbmessung von matten Oberflchen This European Standard was approved by CEN on 7 August 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the stat
7、us of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A
8、 version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czec
9、h Republic, Denmark, Estonia,Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPE
10、N DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 15886:2010: EEN 15886:2010 (E) 2 Contents Page Foreword 31 Scope 42 Normati
11、ve references 43 Terms and definitions .44 Principle 65 Test equipment 65.1 General 65.2 White object colour stimulus 66 Colour measurement of specimens .76.1 Test areas of specimens .76.2 Number of specimens .76.3 Preparation of specimens .77 Colour measurement of indoor and outdoor objects 78 Test
12、 method 78.1 General 78.2 Measuring area and number of measurements 88.3 Reproducibility of measurements 89 Calculation and interpretation of results 89.1 CIELAB values .89.2 Calculation of total colour differences 89.3 Recommended options .810 Test report 9Bibliography . 11DIN EN 15886:2010-12 EN 1
13、5886:2010 (E) 3 Foreword This document (EN 15886:2010) has been prepared by Technical Committee CEN/TC 346 “Conservation of cultural property”, the secretariat of which is held by UNI. This European Standard shall be given the status of a national standard, either by publication of an identical text
14、 or by endorsement, at the latest by March 2011, and conflicting national standards shall be withdrawn at the latest by March 2011. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible f
15、or identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Fran
16、ce, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. DIN EN 15886:2010-12 EN 15886:2010 (E) 4 1 Scope This European Standard describes a test
17、 method to measure the surface colour of porous inorganic materials, and their possible chromatic changes. No reference to the appearance of glossy surfaces is described. The method may be applied to porous inorganic materials either untreated or subjected to any treatment or ageing. The method is s
18、uitable for the measurement of colour coordinates of: representative surfaces of specimens, see 3.11; representative surfaces of objects, indoors or outdoors. 2 Normative references The following referenced documents are required for the application of this standard. For dated references, only the e
19、dition cited applies. For undated references, the latest edition of the referenced documents (including any amendments) apply. prEN 15898:2010, Conservation of cultural property Main general terms and definitions concerning conservation of cultural property 3 Terms and definitions For the purposes o
20、f this document, the terms and definitions given in prEN 15898:2010 and the following apply. 3.1 porous inorganic materials natural stones as well as artificial materials such as mortar, plaster, brick and others 3.2 chroma attribute of colour used to indicate the degree of departure of the colour f
21、rom a grey of the same lightness NOTE See ASTM E 284. 3.3 lightness attribute by which a perceived colour is judged to be equivalent to one of a series of greys ranging from black to white NOTE See ASTM E 284. 3.4 hue attribute of a visual perception according to which an area appears to be similar
22、to one of the colours, red, yellow, green, and blue, or to a combination of adjacent pairs of these colours considered in a closed ring NOTE See the International Commission on Illumination CIE (1931) 3.5 reflectance factor R% percentage ratio of the reflected radiant power compared to incident radi
23、ant power DIN EN 15886:2010-12 EN 15886:2010 (E) 5 3.6 CIE standard illuminant D65 reference illuminant having approximately the same relative spectral power distribution of a phase of daylight with a correlated colour temperature of approximately 6 500 K 3.7 CIE XYZ trichromatic system system for c
24、olour measurement established in 1931 by the International Commission on Illumination CIE (1931) NOTE The interpretation of numerical data is connected directly to visual perception. It is based on the principle that colours are obtained by mixing together the three imaginary colour as primaries def
25、ined X, Y, Z. These primaries define the reference frame in the tristimulus space and any set (X,Y,Z) is a vector in this space. The principal property of the reference frame is that the Y component is the luminance factor, generally given on a percentage scale. 3.8 CIE 1931 standard colorimetric ob
26、server average observer whose colour matching properties correspond to the CIE colour matching functions for the 2 field size 3.9 CIE 1964 standard colorimetric observer average observer whose colour matching properties correspond to the CIE colour matching functions for the 10 field size 3.10 CIE L
27、*a*b* colour space 1976 mathematical transformation of the CIE XYZ space into a metric space NOTE 1 See Figure 1. NOTE 2 The L*a*b* system is useful for calculations of colour differences because it allows them to be defined by numerical values. NOTE 3 In the CIE L*a*b* colour space the colour coord
28、inates in this rectangular coordinate system are: L* - the lightness coordinate. The scale for L* ranges from 0 (black) to 100 (white); a* - the red/green coordinate, with +a* indicating redness and -a* indicating greenness; b* - the yellow/blue coordinate with +b* indicating yellowness and -b* indi
29、cating blueness. a*b*L*fFigure 1 L*a*b* colour space DIN EN 15886:2010-12 EN 15886:2010 (E) 6 3.11 specimen part considered representative of the material constituting an object. NOTE 1 The specimen can have different origins and can be taken from: materials similar to those constituting the object
30、under study (e.g. stone quarries); reference materials, for instance, specifically prepared comparative materials. NOTE 2 The number and dimension of the specimens can be different depending on difficulties encountered in sampling the required amount of material. 4 Principle The method is based on t
31、he determination of the colour of a surface with an instrumental quantification of colour, expressed numerically according to international methods defined by the International Commission on Illumination CIE. The colours are represented in a “colour space“, where any colour in the visible range is d
32、efined by three coordinates. 5 Test equipment 5.1 General Common instruments used for colour measurement are tristimulus colorimeters or reflectance spectrophotometers characterized by: spectral range: 380 nm to 780 nm; acquisition data at least every 10 nm; CIE standard illuminant: D65 (recommended
33、), A, C; CIE standard colorimetric observer: 2 and 10 (recommended); reference system colour space: CIE x,y,Y and L*a*b*1). It is recommended that the instrument geometry conforms to the d/8 illumination and viewing condition specified by the CIE, where the illumination is diffused with the specular
34、 component excluded. Use of other geometries, such as 0/d, is also allowed. The test report shall specify the geometry used. 5.2 White object colour stimulus For the calculation of L*a*b* values, the white reference shall be constituted by a perfect reflecting diffuser illuminated by the same light
35、source as the tested specimen and/or object. 1) Usually the instruments available on the market are equipped with a software, which calculates the colorimetric parameters CIE x,y,Y and L*,a*,b* from the reflectance values. Otherwise these parameters can be calculated using theCIE Tables. DIN EN 1588
36、6:2010-12 EN 15886:2010 (E) 7 6 Colour measurement of specimens 6.1 Test areas of specimens The tested surface areas shall be representative of the colour of the material under investigation. On inhomogeneous materials, the number of measurement points shall be adapted to the specimen as to obtain s
37、tatistically representative values. Specimens shall be large enough to extend beyond the measurement area of the instrument. 6.2 Number of specimens A minimum of five representative specimens is considered suitable. However, if only a limited number of specimens are available, the most representativ
38、e specimen(s) shall be used. 6.3 Preparation of specimens The specimens shall be conditioned in equilibrium with the surrounding environment. Temperature (T) and Relative Humidity (RH) should be recorded. The surface of the specimens to be measured shall, if strictly necessary, be smoothed with sand
39、 paper with grain size of 82 m (corresponding to grit number P180 according to the FEPA2)classification) and wiped with a soft brush, bearing in mind that such action may alter the colour of the surface prior to measurement. Measurements taken before and after treatment shall be performed under the
40、same environmental conditions. 7 Colour measurement of indoor and outdoor objects The area of measurement is the section of the surface of the object on which the colour measurements are carried out. The surface to be measured should, as far as practicable, be smooth and flat so as exclude external
41、light from the area of measurement. Where no smooth, flat areas are available, this should be noted in the report. Sand paper shall not be used to smooth the surface of an object. Environmental parameters should, as far as is practicable, be reproduced when measurements are made. Relevant environmen
42、tal conditions, including temperature and humidity should be recorded in the report. Colour measurements before and after treatment, and any subsequent measurement, should be carried out under the same environmental conditions. 8 Test method 8.1 General The surface to be measured shall be representa
43、tive of the specimen and the object as a whole. The number of measurement points shall be adapted to the specimen or the object as to obtain statistically representative values. 2) FEPA Federation of European Producers of Abrasives. DIN EN 15886:2010-12 EN 15886:2010 (E) 8 8.2 Measuring area and num
44、ber of measurements The diameter of the measuring area and the equipment shall be appropriate to the type of material under investigation, and the size of the specimen or object. Heterogeneous surfaces may be measured using a measuring area with a diameter as large as possible, in order to compensat
45、e variations in colour and texture, and to even out structural unevenness on the surface of the specimen or object, thus imitating the human visual process. Uniform specimens or objects with or without well-defined areas of different appearance (such as dark veins on light marble) may be measured wi
46、th a much smaller (1 mm) measuring field diameter to avoid (or define) any areas of in-homogeneity. The necessary number of measurements varies according to the homogeneity of the measuring area, but shall be at least five to obtain a reliable average value per specimen or per object. The measuremen
47、ts are taken at arbitrary locations of the surface In order to ensure precise repeated measurements, the selected measurement points shall be localised by either reference spatial coordinates or by annotated images. A grid delimiting the measurement area may be useful for this purpose, depending on
48、the size of the specimen or the object. 8.3 Reproducibility of measurements Reproducibility of measurements is assessed by comparing two series of measurements made on the same surface under the same conditions and at different times, defined as moving the measuring head/probe turning the instrument
49、 on and off, and recalibrating it. Repeat the measurements until the difference, expressed as E, between the average L* a* b* values of two successive series of measurements is E 1,5. 9 Calculation and interpretation of results 9.1 CIELAB values Calculate the CIELAB (CIE L* a* b* 1976) values from the X, Y, Z values for each specimen. Daylight illuminant (D65) and 10 observer should be used. 9.2 Calculation of total colour differences The total colour difference E* be
