1、STD-BSI BS EN IS0 11985-ENGL 1998 1624bb9 0693452 312 BRITISH STANDARD Ophthalmic optics - Contact lenses - Ageing by exposure to UV and visible radiation (in vitro method) The European Standard EN IS0 11985 : 1997 has the status of a British Standard ICs 11.040.70 BS EN IS0 11985 : 1998 NO COPYING
2、WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGRT LAW National foreword AmdNo. This British Standard is the English language version of EN IS0 11985 : 1997. It is identical with IS0 11985 : 1997. The UK participation in its preparation was entrusted by Technical Committee CWS, Ophthalmic optic
3、s, to Subcommittee CHRW4, Physical properties of contact lenses, which has the responsibility to: Date Text affected - aid enquirem to understand the text; - present to the responsible intemationaYEuropean committee any enquiries on the interpretation, or proposals for change, and keep the UK intere
4、sts informed; - monitor related intemational and European developments and promulgate them in the UK. A list of organhiions represented on this subcommittee can be obtained on request to its secretary. Cross-references Attention is drawn to the fact that CEN and CENELEC standards normally include an
5、 annex which lists normative references to intemationai pubiications with their corresponding European publications. The British Standards which implement these intemational or European publications may be found in the BSI Standards Catalogue under the section entitled International Standards Corres
6、pondence Index, or by using the Find facility of the BSI Standards Electronic Catalogue. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside nont cover, the EN IS0 title page, the EN IS0 forew
7、ord page, the EN title page, page ii, pages 1 to 6, an inside back cover and a back cover. This British Standard, having been prepared under the direction of the Heaith and Environment Sector Board, was published under the authority of the Standards Board and comes into effect on 15 April 1998 CP BS
8、I 19% ISBN O SSO 29381 6 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN IS0 11985 December 1997 ICs 11.040.70 Descriptors: see IS0 document English version Ophthalmic optics - Contact lenses - Ageing by exposure to UV and visible radiation (in vitro method) (IS0 1 1985:1997) Optique ophtalmiqu
9、e - Lentilles de contacl - Vieillissement des lentilles de contact par exposition aux rayonnements UV et visible (mthode in vitro) (IC0 11 985:1997) Augenoptik - Kontaktlinsen - Alterung durch Einwirkung von ultravidetter und sichtbarer Strahlung (in vitro-Verfahren) (IS0 11985:1997) This European S
10、tandard was approved by CEN on 4 December 1997. CEN members are bound to comply with the CENICENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concern
11、ing such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists 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 la
12、nguage and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria. Belgium, Czech Republic. Denmark, Finland, France, Germany, Greece, Iceland, Ireland. Italy, Luxembourg, Netherlands, Norway, Portugal. Spain, Sweden
13、, Switzerland and United Kingdom. * * rn EUROPEAN COMMllTEE FOR STANDARDIZATION EUROPISCHES KOMITEE FOR NORMUNG COMITE EUROPEEN DE NORMALISATION Central Secmtarlat: rue de Stassart, 36 E1 O50 Bru8sals 0 1997 CEN All rights of exploitation in any form and by any means resewed worldwide for CEN nation
14、al Members. Ref. No. EN IS0 11 985:1997 E Foreword The text of the International Standard IS0 1 1 985: 1997 has been prepared by Technical Committee ISO/TC 172 “Optics and optical instruments“ in collaboration with Technical Committee CEN/TC 170 “Ophthalmic optics“, the secretariat of which is held
15、by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 1998, and conflicting national standards shall be withdrawn at the latest by June 1998. According to the CENKENELEC Internal Regulation
16、s, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Itaty, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United
17、 Kingdom. Endorsement notice The text of the International Standard IS0 1 1985: 1997 was approved by CEN as a European Standard without any modification. STD.BS1 BS EN IS0 11985-ENGL 1998 Lb24669 0693456 Tb8 = EN IS0 11985 : 1997 INTERNATIONAL STANDARD IS0 11985 First edition 1997-1 2-1 5 Ophthalmic
18、 optics - Contact lenses - Ageing by exposure to UV and visible radiation (in vitro method) Optique ophtalmique - Lentilles de contact - Vieillissement par exposition aux rayonnements UV et visible (mthode in vitro) * * vi Reference number IS0 1 1985: 1997(E) EN IS0 11985 : 1997 Foreword IS0 (the In
19、ternational Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies). The work of preparing international Standards is normally carried out through IS0 technical committees. Each member body interested in a subject for which a technical Committee h
20、as been established has the right to be represented on that committee. International organisations, governmental and non- governmental, in liaison with ISO, also take part in the work. IS0 collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnica
21、l standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard IS0 1 1985 was prepared by ISO/
22、TC 172 Optics and optical instruments, Subcommittee SC 7, Ophthalmic optics and instruments. Descriptors: optics, optical equipment, ophthalmic equipment, contact lenses, ageing (materials), ageing tests (materials), artificial light tests, colar radiation, ultraviolet radiation. II - STD-BSI BS EN
23、IS0 11985-ENGL 1998 1624669 0693458 830 a EN IS0 11985 : 1997 Ophthalmic optics - Contact lenses - Ageing by exposure to UV and visible radiation (in vifro method) 1 Scope This International Standard describes an in vitro method which simulates the ageing of rigid (hard) and sof lenses in daylight.
24、The existence of this International Standard does not imply in any way that the testing of contact lenses for ageing by ultraviolet (UV) and visible radiation is a requirement. 7 2 Normative reference - The following standard contains provisions which, through reference in this text, constitute prov
25、isions of this International Standard. At the time of the publication, the edition indicated was valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent edition of the stand
26、ard indicated below. Members of IEC and IS0 maintain IS0 10344:1996, _I e - - _I e I * m * registers of currently valid International Standards. Optics and optical instruments - Contact lenses - Saline solution for contact lens testing., 3 Principle One aspect of the ageing of contact lenses in norm
27、al use is simulated by exposure to an intense source of light. 4 Apparatus 4.1 Hlgh pressure xenon lamp, with a quartz envelope and with filters giving a spectral distribution corresponding to that of solar radiation. NOTE 1 An example of such a lamp is shown in figure 1. NOTE 2 High intensity UV so
28、urces present radiation hazards if not properly shielded and safety hazards if not properly maintained. 4.2 Infrared (IR) filter, with a transmittance of less than 50 YO of the incident radiation in the range 650 nm to 850 nm. NOTE - An example of the transmittance of an IR filter is shown in figure
29、 2. 1 EN IS0 11985 : 1997 “ 2?0 300 400 500 600 ?O0 800 C) d) e) ai - - Xenon lamp spectrum Global solar spectrum at sea level (D, illuminant) a) Wavelength, in nm b) Spectral irradiance, in W/(m2 5 nm) d) visible e) IR c) UV Figure 1 - Energy distribution 4.3 Ultraviolet (UV) filter, with a transmi
30、ttance corresponding to solar radiation. The transmittance shall be O YO below a wavelength of 290 nm and greater than 90 % between wavelengths of 380 nm and 750 nrn. NOTE - An example of the effect of such a UV filter is shown in figure 3. 4.4 Mirrors, two, capable of reflecting UV and visible radi
31、ation. 4.5 Radiation source, comprising a xenon lamp (4.1), IR filter (4.2), UV filter (4.3), mirrors (4.4) and parabolic reflector assembled as shown in figure 4. 4.6 Cuvette, manufactured from quartz and designed to hold contact lens(es). It shall be provided with a silicone rubber seal retained i
32、n position using a suitable clamp. When filled with standard saline solution (IS0 10344), the cuvette shall not absorb more than 2 % of incident radiation between the wavelengths 290 nm and 750 nm. NOTE - Such an arrangement retaining two cuvettes is shown in figure 5. 2 * * v1 CICI 350 360 3f0 380
33、390 STD.BSI BS EN IS0 11985-ENGL 1998 1624669 0693460 499 EN IS0 11986 : 1997 400 -200 2f0 340 410 480 550 620 690 ?60 830 900 a) - a) Wavelength, in nm b) % Transmittance Figure 2 - IR filter transmittance I 270 280 290 3oo 310 . O 330 340 a) - - Without UV filter With UV filter a) Wavelength, in n
34、m b) Spectral irradiance, in W/(m . 5 nm) Figure 3 - UV domain of xenon lamp 3 STD-BSI BS EN IS0 LLSB5-ENGL 1998 1624669 06934bL 325 EN IS0 11985 : 1997 Dimensions in millimetres t 32 1 1 Cuvette (see cuvette assembly shown in figure 5) 2 Saline solution 3 Contact lens 4 UV - visible rays 5 IR rays
35、6 Xenonlamp 7 UV reflecting mirror 8 Visible reflecting mirror 9 IRfilter 10 UV filter 11 Parabolic reflector Figure 4 - Radiation source and apparatus 4 STDmBSI BS EN IS0 11985-ENGL 1998 1b2Ybb9 0693462 2-61 m EN IS0 11986 : 1997 Dimensions in millimetres 1 Silicone rubber seal 2 Saline solution 3
36、Contact lens Cuvette holder Cuvette Figure 5 - Cuvette assembly 5 EN IS0 11986 : 1997 5 Samples Take the new unused contact lenses from the normal production process. Ensure that no lens has been specially treated or conditioned prior to the test. 6 Procedure 6.1 Place one sample lens in each cuvett
37、e (4.6). Fill the cuvette with the saline solution conforming to IS0 10344. Place the silicone rubber seal on the tip of the cuvette. Ensure that there are no air bubbles. Fix the seal in position with the clamp. 6.2 Ensure that the total irradiance between 300 nm and 800 nm is 240 W/m2 to 260 W/m2
38、and that, if more than one lens is exposed simultaneously, each lens is subjected to the same irradiation. Ensure that the irradiation is essentially perpendicular to the surface on which the sample rests. Expose the samples to the light source (see 4.5) at a distance of (295 f 5) rnm for (20 +i) h
39、unless otherwise specified by the manufacturer. During the exposure, ensure that the temperature of the saline solution in the cuvette remains below 40 “C. 7 Testreport The test report shall contain at least the following information : a) a reference to this International Standard, .e. IS0 11985; b)
40、 the identification of the contact lens submitted to the procedure; c) the date of submission of the contact lens to the procedure. 6 BS EN IS0 11985 : 1998 BSI 389 Chiswick High Road London w4 4AL STD.BSI BS EN IS0 11985-ENGL I1998 W 1624669 0693464 034 BSI - British Standards Institution BSI is th
41、e independent national body responsible for preparing British standards. It presents the UK view on standards in Europe and at the internaiional level. It is incorporated by Royal Charter. Contract requirements A British standard does not purport to include all the necessary provisions of a contract
42、 Users of British Standards are responsible for their correct application. Revisions British Standards are updated by amendment or revision. Users of British Standards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our pr
43、oducts and services. We would be grateful if anyone nding an inaccuracy or ambiguity while using this British Standard would inform the Secretary of the responsible technical committee, the identity of which can be found on the inside front cover. Tel 0181 996 9o00, Fax: 0181 996 7400. BSI offers me
44、mbers an individuai updating service called PLUS which ensures that subscribers automaticaiiy receive the latest editions of standards. Buying standards Orders for all BSI, internatioml and foreign standards publications should be addressed to Customer Services, Sales Depariment at Chiswick Tek 0181
45、 996 7000; Fax: 0181 996 7001. In response to orders for international standards, it is BSI poiicy to supply the BSI implementaion of those that have been published as British Standards, unless otherwise requested. Information on standards BSI provides a wide range of information on national, Europe
46、an and international standards through its iibrary, the Standardline Database, the BSI Informhon Technology Service (Bm) and its Technical Help to Exporters Service. Contact the information Department at Chiswick Tel 0181 996 7111; Fax: 0181 996 7048. Subscribing members of BSI are kept up to date w
47、ith standars developments and receive substantial discounts on the purchase price of standards. For details of these and other benefits contact Customer Services, Membership at Chiswick Tek 0181 996 7002; Fax: 0181 996 7001. Copyright Copyright subsists in all BSI pubications. BSI also holds the cop
48、yright, in the UK, of the publications of the intedonal stan-on bodies. Except as permitted under the Copyright, Designs and Patents Act 1988 no extract may be reproduced, stored in a relxievai system or transmitted in any form or by any means - electronic, photocopying, recording or otherwise - wit
49、hout prior written permission hm BSI. This does not preclude the free use, in the course of implementing the standard, of necessary details such as symbols, and size, type or grade designations. if these details are to be used for any other purpose than implementation then the prior written permission of BSI must be obtained- if permission is granted, the tem may include royalty payments or a licensing agreement. Details and actvice can be obtained from the Copyright Manager, BSI, 389 Chiswick High Road, London W4 4AL
