1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 24443:2012Determination of sunscreenUVA photoprotection in vitro(ISO 24443:2012)BS EN ISO 24443:2012 BRITISH STANDARDNational forewordThis British Standard is the UK im
2、plementation of EN ISO24443:2012.The UK participation in its preparation was entrusted to TechnicalCommittee CW/217, Cosmetics.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of
3、a contract. Users are responsible for its correctapplication. The British Standards Institution 2012. Published by BSI StandardsLimited 2012ISBN 978 0 580 61110 0ICS 71.100.70Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the
4、 authority of theStandards Policy and Strategy Committee on 30 June 2012.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 24443 June 2012 ICS 71.100.70 English Version Determination of sunscreen UVA photoprotection in vitro (ISO 24443:2012
5、) Dtermination in vitro de la photoprotection UVA (ISO 24443:2012) In vitro Bestimmung des UVA-Schutzes von Sonnenschutzmitteln (ISO 24443:2012) This European Standard was approved by CEN on 24 May 2012. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the co
6、nditions for giving this European Standard the status 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-CENELEC Management Centre or to any CEN member. This European Standard exi
7、sts 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 st
8、andards 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, T
9、urkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. E
10、N ISO 24443:2012: EBS EN ISO 24443:2012EN ISO 24443:2012 (E) 3 Foreword This document (EN ISO 24443:2012) has been prepared by Technical Committee ISO/TC 217 “Cosmetics“ in collaboration with Technical Committee CEN/TC 392 “Cosmetics” the secretariat of which is held by AFNOR. This European Standard
11、 shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by December 2012, and conflicting national standards shall be withdrawn at the latest by December 2012. Attention is drawn to the possibility that some of the elements of th
12、is document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Sta
13、ndard: 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and t
14、he United Kingdom. Endorsement notice The text of ISO 24443:2012 has been approved by CEN as a EN ISO 24443:2012 without any modification. BS EN ISO 24443:2012ISO 24443:2012(E) ISO 2012 All rights reserved iiiContents PageForeword iv1 Scope 12 Terms and definitions . 13 Principle . 24 Apparatus 24.1
15、 UV spectrophotometer specifications . 24.2 Calibration of the UV spectrophotometer . 34.3 Calibration of the UV exposure source 34.4 Monitoring of the UV exposure source . 34.5 Calibration of the UVA radiometer used to monitor the test sample irradiation 44.6 Substrate/plate . 45 Test method 45.1 O
16、utline of the test procedure . 45.2 Equipment calibration and validation of test plates 45.3 Absorption measurements through the plate . 55.4 Sample application . 55.5 Absorbance measurements of the product-treated plate 55.6 Number of determinations 55.7 Determination of initial calculated SPF (SPF
17、in vitro), “C” value, initial UVAPF(UVAPF0), and UV exposure dose 55.8 UV exposure . 75.9 Measurement of final adjusted absorbance spectrum 75.10 Calculation of UVAPF of plates after UV exposure of the sample . 86 Procedure using the spreadsheet in this International Standard 87 Reference sunscreen
18、formula S2 98 Test report . 9Annex A (normative) Calibration of UV spectrophotometer and plate transmission test 10Annex B (normative) Radiometer calibration to spectroradiometric irradiance procedure 14Annex C (normative) Computation values: PPD and erythema action spectra and UVA and UV-SSR spectr
19、al irradiances 16Annex D (normative) PMMA test plate surface specifications .19Annex E (normative) UVA reference sunscreen S2 .21Annex F (informative) Statistical calculations 25Bibliography .27BS EN ISO 24443:2012ISO 24443:2012(E)ForewordISO (the International Organization for Standardization) is a
20、 worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represente
21、d on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Standards are draft
22、ed in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Stand
23、ard requires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.iv ISO 2012 All rights rese
24、rvedBS EN ISO 24443:2012INTERNATIONAL STANDARD ISO 24443:2012(E)Determination of sunscreen UVA photoprotection in vitro1 ScopeThis International Standard specifies an in vitro procedure to characterize the UVA protection of sunscreen products. Specifications are given to enable determination of the
25、spectral absorbance characteristics of UVA protection in a reproducible manner. In order to determine relevant UVA protection parameters, the method has been created to provide a UV spectral absorbance curve from which a number of calculations and evaluations can be undertaken. Results from this mea
26、surement procedure can be used for other computations, as required by local regulatory authorities. These include calculation of the Ultraviolet-A protection factor (UVAPF) correlating with in vivo UVAPF from the persistent pigment darkening (PPD) testing procedure, critical wavelength and UVA absor
27、bance proportionality. These computations are optional and relate to local sunscreen product labelling requirements. This method relies on the use of in vivo SPF results for scaling the UV absorbance curve.This International Standard is not applicable to powder products such as pressed powder and lo
28、ose powder products.2 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.2.1in vitro UVA protection factorUVAPFin vitro UVA protection factor of a sun protection product against UVA radiation, which can be derived mathematically with in vitro spectral m
29、odelling2.2in vitro calculation of SPFSPFin vitroprotection factor of a sun protection product against erythema-inducing radiation calculated with spectral modelling2.3action spectrum for erythemaE(l)relative effects of individual spectral bands of an exposure source for an erythema responseNOTE See
30、 References 1 and 2.2.4action spectrum for PPDP(l)relative effects of individual spectral bands of an exposure source for a persistent pigment responseNOTE See References 3 and 4.2.5monochromatic absorbanceAlsunscreen absorbance at wavelength, l, related to the sunscreen transmittance, Tl, byAl= - l
31、og (Tl)where transmittance, Tl, is the fraction of incident irradiance transmitted by the sunscreen film ISO 2012 All rights reserved 1BS EN ISO 24443:2012ISO 24443:2012(E)2.6irradianceIfluence rate per unit area, expressed in W/m2, for a defined range of wavelengthsEXAMPLE From 290 nm to 400 nm for
32、 UVA + UVB irradiance; from 320 nm to 400 nm for UVA irradiance.2.7spectral irradiance for SPF testing or PPD testingI(l)irradiance per unit wavelength, I(l) , expressed in W/m2/nm2.8spectrophotometerinstrument that measures absorbance (or transmission) properties of a test medium as a function of w
33、avelength2.9spectroradiometerinstrument that measures spectral irradiance (intensity in watts per unit area per nanometre) of electromagnetic sourcesNOTE Limited to ultraviolet, visible and short infrared ranges in this International Standard.2.10radiometerinstrument that measures broad band irradia
34、nce (intensity in watts per unit area) of electromagnetic sourcesNOTE Limited to ultraviolet, visible and short infrared ranges in this International Standard.3 PrincipleThe test is based on the assessment of UV-transmittance through a thin film of sunscreen sample spread on a roughened substrate, b
35、efore and after exposure to a controlled dose of radiation from a defined UV exposure source. Because of the several variables that cannot be controlled with typical thin film spectroscopic techniques, each set of sunscreen transmission data is mathematically adjusted so that the in vitro SPF data y
36、ield the same measured in vivo SPF value that was determined by in vivo testing. Samples are then exposed to a specific measured dose of UV radiation to account for the photostability characteristics of the test product. The resulting spectral absorbance data have been shown to be a useful represent
37、ation of both the width and height of the UVA protection characteristics of the sunscreen product being tested. The mathematical modelling procedure has been empirically derived to correlate with human in vivo (persistent pigment darkening) test results.4 Apparatus4.1 UV spectrophotometer specificat
38、ionsThe UV spectrophotometer wavelength range shall span the primary waveband of 290 nm to 400 nm. The wavelength increment step shall be 1 nm.A UV spectrophotometer that does not have a monochromator after the test sample should employ a fluorescence rejection filter.The UV spectrophotometer input
39、optics should be designed for diffuse illumination and/or diffuse collection of the transmitted irradiance through the roughened polymethylmethacrylate (PMMA) substrate, with and without the sunscreen layer spread on its surface. The size of the diameter of the entrance port of the UV spectrophotome
40、ter probe shall be smaller than the size of the light spot to be measured at the sample level (in order to account for stray light). The area of each reading site should be at least 0,5 cm2in order to reduce the variability between readings and to compensate for the lack of uniformity in the product
41、 layer. The wavelength should be accurate to within 1 nm, as checked using a holmium-doped filter (see Annex A). The ability of an instrument to accurately measure absorbance is limited by the sensitivity of the instrument. The minimum 2 ISO 2012 All rights reservedBS EN ISO 24443:2012ISO 24443:2012
42、(E)required dynamic range for this methodology is 2,2 absorbance units as determined according to Annex A. The maximum measured absorbance should be within the dynamic range of the device used. If the test measurements yield absorbance curves that exceed the determined upper limit of the UV spectrop
43、hotometer, the product should be re-tested using an instrument with increased sensitivity and dynamic range.The lamp in the UV spectrophotometer that is used to measure the transmittance shall emit continuous radiation over the range of 290 nm to 400 nm, and the level of irradiance should be suffici
44、ently low, so that the photostability of the product is not unduly challenged (a xenon flash lamp is a convenient solution). Therefore the UV dose during one measurement cycle should not exceed 0,2 J/cm2.NOTE A UV spectrophotometer is used to measure the absorbance properties of the sunscreen on the
45、 test plates. A spectroradiometer is used to measure the spectral energy distribution and intensity of the UV exposure source or the UV spectrophotometer during the absorbance measurement of the sunscreen on the test plate.4.2 Calibration of the UV spectrophotometerThe UV spectrophotometer shall be
46、validated at regular intervals (recommended at least every month) by measurements of reference materials.A three-fold test is required, as described in Annex A: dynamic range of the UV spectrophotometer; linearity test of the UV spectrophotometer; wavelength accuracy test.4.3 Calibration of the UV e
47、xposure source The spectral irradiance at the exposure plane of the UV exposure source that is used for irradiation (to take into account any photoinstability) shall be as similar as possible to the irradiance at ground level under a standard zenith sun5as defined by COLIPA6or in DIN 675017. The UV
48、irradiance shall be within the following acceptance limits (measured at sample distance).Table 1 UV exposure source specificationsUV exposure source specifications as measured with a spectroradiometerTotal UV irradiance (290 nm to 400 nm) 40 W/m2to 200 W/m2Irradiance ratio of UVAato UVBb8:22a320 nm
49、to 400 nm.b290 nm to 320 nm.The UV exposure source device should have the ability to maintain samples within the range of 25 C to 35 C. It is important that the temperature of the sample itself be measured and not just the surrounding air temperature. To maintain samples at a temperature less than or equal to 35 C, a filter system that particularly reduces IR radiation should be used to achieve the specified temperature range. Cooling trays for the sample plates or ventilators should be used to maintain a temperature below 35 C and warming d
