1、BRITISH STANDARD Personal eye-protection Optical test methods The European Standard EN 167:2001 has the status of a British Standard ICs 13.340.20 BS EN 167:2002 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BS EN 167:2002 Amd. No. National foreword Date Comments This Britis
2、h Standard, having been prepared under the direction of the Health and Environment Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 28 January 2002 This British Standard is the official English language version of EN 167:2001.
3、It supersedes BS EN 167:1995 which is withdrawn. The UKparticipation in its preparation was entrusted by Technical Committee PH/2, Eye protection, to Subcommittee PH/2/2, Industrial eye protectors, which has the responsibility to: - - aid enquirers to understand the text; present to the responsible
4、European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. - A list of organizations represented on this subcommittee can be obtained on request to its sec
5、retary. Cr oss-r e fer enc e s The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI S
6、tandards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of
7、 pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 27 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. O BSI 28 January 2002 ISBN O 580 38915 4 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE
8、 NORM EN 167 November 2001 ICs 13.340.20 Supersedes EN 167:1995 English version Personal eye-protection - Optical test methods Protection individuelle de loeil - Mthodes dessais optiques Persnlicher Augenschutz - Optische Prfverfahren This European Standard was approved by CEN on 3 September 2001. C
9、EN members are bound to comply with the CENKENELEC 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 concerning such national standards may be obtained on app
10、lication to the Management Centre 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 language and notified to the Management Centre has the
11、 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, Switzerland and United Kingdom. EUROPEAN COMMITTEE F
12、OR STANDARDIZATION EUROPISCHES KOMITEE FR NORMUNG COMIT EUROPEN DE NORMALISATION Management Centre: rue de Stassart, 36 B-1050 Brussels O 2001 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 167:2001 E EN 167:2001 (E) Contents page
13、 Foreword 3 1 2 3 3.1 3.2 4 4.1 4.2 5 6 7 7.1 7.2 7.3 8 Scope 4 Normative references 4 Test for spherical. astigmatic and prismatic refractive powers 4 Testing unmounted oculars covering one eye . 4 Testing unmounted oculars covering both eyes and mounted oculars (spectacles. goggles and face-shield
14、s) 6 Light diffusion test . 8 Principle 8 Test methods 8 Assessment of quality of material and surface 14 Determination of transmittance 14 Determination of variations in luminous transmittance 15 Unmounted oculars covering one eye . 15 Mounted oculars and unmounted oculars covering both eyes 16 Met
15、hod to correct transmittance for variations in thickness of the ocular . 17 Determination of spectral reflectance in infrared . 18 Annex A (normative) Method for measuring spherical and astigmatic refractive powers over small areas 19 A.l Principle 19 A.2 Apparatus . 19 A.3 Measurements 20 Annex B (
16、informative) Uncertainty of measurement and results interpretation . 25 B.l Test report and uncertainty of measurement . 25 Annex ZA (informative) Clauses of this European Standard addressing essential requirements or other provisions of EU Directives 27 2 EN 167:2001 (E) Foreword This document has
17、been prepared by Technical Committee CEN /TC 85, “Eye-protective equipment“, the secretariat of which is held by AFNOR. 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 May 2002, and conflicting na
18、tional standards shall be withdrawn at the latest by May 2002. This European Standard replaces EN 167:1995. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). For rel
19、ationship with EU Directive(s), see informative annex ZA, which is an integral part of this document. Annex A is normative. The annexes B and ZA are informative. According to the CENKENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement t
20、his European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 3 EN 167:2001 (E) 1 Scope This European Standard specifies optical test methods f
21、or eye-protectors, the requirements for which are contained in other ENS. Alternative methods may be used if shown to be equivalent. Non-optical test methods are given in EN 168. Specifications are given in EN 166. A definition of terms is given in EN 165. 2 Normative references This European Standa
22、rd incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to
23、this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN 165, Personal eye-protection - Vocabulary. EN 1 66, Personal eye-protection - Specifications. EN 1 68, Personal ey
24、e-protection - Non-optical test methods. 3 Test for spherical, astigmatic and prismatic refractive powers NOTE The reference methods for assessment of refractive power are contained in 3.1 and 3.2. If during measurement using the telescope a doubling or other aberration of the image is observed then
25、 the ocular may either be classified as a defective, or subjected to further examination using the method described in annex A. 3.1 Testing unmounted oculars covering one eye 3.1 .I Apparatus 3.1 .I .I Telescope A telescope with an aperture of nominally 20 mm and a magnification between 10 and 30, f
26、itted with an adjustable eyepiece incorporating a reticule. 3.1.1.2 Illuminated target A target, consisting of a black plate incorporating the cut-out pattern shown in Figure 1, behind which is located a light source of adjustable luminance with a condenser, if necessary, to focus the magnified imag
27、e of the light source on the telescope objective. The large annulus of the target has an outer diameter of (23,O f 0,l) mm with an annular aperture of (0,6 f 0,l) mm. The small annulus has an inner diameter of (11,O f 0,l) mm with an annular aperture of (0,6 f 0,l) mm. The central aperture has a dia
28、meter of (0,6 f 0,l) mm. The bars are nominally 20 mm long and 2 mm wide with a nominal 2 mm separation. 4 EN 167:2001 (E) 3.1 .I .3 Filter A filter with its maximum transmittance in the green part of the spectrum may be used to reduce chromatic aberrations. 3.1 .I .4 Calibration lenses Lenses with
29、positive and negative spherical refractive powers of 0,06 m-I, 0,12 m-l and 0,25 m-l (tolerance f O,OI m-I). 3.1.2 Arrangement and calibration of apparatus The telescope and illuminated target are placed on the same optical axis (4,60 f 0,02) m apart. The observer focuses the reticule and the target
30、 and aligns the telescope to obtain a clear image of the pattern. This setting is regarded as the zero point of the focusing scale of the telescope. The telescope shall be aligned so that the central aperture of the target is imaged on the centre of the cross-line graticule. This setting is regarded
31、 as the zero point of the prism scale. The focusing adjustment of the telescope is calibrated with the calibration lenses (3.1.1.4) so that a power of 0,Ol m-l may be measured. Any other equivalent calibration method may be used. 3.1.3 Procedure Position the ocular in front of the telescope in the a
32、s-worn position, or other position as specified by the manufacturer. If the as-worn position is unknown, or if no position is specified by the manufacturer then the ocular shall be positioned normal to the telescopic axis and the tests conducted at the geometric centre. 3.1.3.1 Spherical refractive
33、power and astigmatic refractive power 3.1.3.1 .I Oculars without astigmatic refractive power The telescope is adjusted until the image of the target is clearly focussed. The spherical power of the ocular is then read from the scale of the telescope. 3.1.3.1.2 Oculars with astigmatic refractive power
34、 The target, or the ocular, is rotated in order to align the principal meridians of the ocular with the bars of the target. The telescope is focused firstly on one set of bars (measurement 01) and then on the perpendicular bars the astigmatic refractive power is the absolute (measurement 02). The sp
35、herical power is the mean, difference, ID, - D2 I, of the two measurements. Dl +D2 2 NOTE During this process the best focus shall be used across the whole target for each meridian. 3.1.3.2 Prismatic refractive power The ocular to be tested is placed in front of the telescope, and, if the point of i
36、ntersection of the lines of the reticule falls outside the image of the large circle, the prismatic power exceeds 0,25 cm/m. If the point of intersection of the lines of the reticule falls inside the image of the small circle of the target, the prismatic power is less than 0,12 cm/m. 5 EN 167:2001 (
37、E) Figure - Telescope target (dimensions are given in 3.1. 2) 3.2 Testing unmounted oculars covering both eyes and mounted oculars (spectacles, goggles and face-shields) 3.2.1 Determination of the spherical and astigmatic refractive power Position the ocular such that it is in an “as-worn” orientati
38、on in front of the telescope. Measurements of spherical and astigmatic powers shall be taken based on the visual centre of the ocular using the procedures specified in 3.1.3.1. 3.2.2 3.2.2.1 Apparatus The arrangement of the reference method is shown in Figure 2. 3.2.2.2 Procedure The diaphragm LB1,
39、illuminated by the light source, is adjusted in such a way that it produces an image on the plane B when the eye-protector (P) is not in position. The eye-protector is placed in front of the lens L2 in the as- worn position so that the axis of the eye-protector is parallel to the optical axis of the
40、 test assembly. Adjustable tilt eye-protectors are positioned with their oculars normal to the optical axis of the test equipment. Measure the vertical and horizontal distances between the two displaced images arising from the two ocular regions of the eye-protector. These distances in centimetres a
41、re divided by two to give the horizontal and vertical prismatic differences in centimetres per metre. If the light paths which correspond to the two eye regions cross, the prismatic refractive power is base in and if the light paths do not cross, it is base out. Determination of the difference in pr
42、ismatic refractive power 6 EN 167:2001 (E) Dimensions in millimetres (nominal unless toleranced) A LB 2 B La Light source, for example, small filament lamp, laser with wavelength of (600 f 70) nm, etc. J Interference filter with peak transmittance in the green part of the spectrum (required only if
43、a filament lamp is used as the light source) LI Achromatic lens, focal length between 20 mm and 50 mm LBI Diaphragm, diameter of aperture 1 mm nominal P Eye-protector LB2 Diaphragm as shown in detail A L2 Achromatic lens, 1 O00 mm nominal focal length and 75 mm nominal diameter B Image plane a As cl
44、ose as possible. X = (32,O f 0,2) mm or (27,O f 0,2) mm depending on the size of the head-form specified in EN 168. Figure 2 - Arrangement of apparatus for measurement of prismatic difference 7 EN 167:2001 (E) 4 Light diffusion test 4.1 Principle The luminance (L,) of an illuminated ocular is a meas
45、ure of its light diffusion and is proportional to the illuminance (Ej. The proportionality factor is the luminance factor I= L,/E, which is expressed in candelas per square metre per lux (cd / m ) Ix To obtain a factor + which is independent of the transmittance of the ocular, the luminance factor i
46、s divided by the transmittance T. This quantity is known as the reduced luminance factor and is expressed in the same units as the luminance factor. NOTE Most oculars have diffusion properties which are symmetrical about the optical axis. For these oculars, the mean value of the reduced luminance fa
47、ctor is measured within an angle limited by the two cones shown in Figure 3. This mean value depends upon values a and Aa. 2 1 2 3 Key 1 2 Diffused light 3 Ocular Incident light on optical axis Figure 3 - Diffusion angles 4.2 Test methods Two test methods are specified which use the same measurement
48、 principle. The basic method detailed in 4.2.1 may be used for oculars without corrective effect and for all shade numbers. The simplified method detailed in 4.2.2 has to be used for oculars with corrective effect. The results obtained with the two methods may be considered to be equivalent; whichev
49、er method is used the relative measurement uncertainty for the reduced luminance factor shall not be greater than 25 %. Measurements of light diffusion shall be taken at the visual centre of the ocular. If the visual centre is not known then the geometric centre shall be used. NOTE Visual centre is as defined in EN 166. 8 EN 167:2001 (E) 4.2.1 Basic method 4.2.1 .I Apparatus The arrangement is shown in Figure 4. The spherical concave mirror Hl forms an image of light L of identical dimensions at diaphragm LB. The spherical concave mirror H3 forms an image of diaphragm LB i
