00071693 PDF BRITISH STANDARD AUTOMOBILE SERIES CONFIRMED SEPTEMBER 1990 BS AU 152 1970 Specification for Rear marking plates for vehicles Confirmed February 2011 BS AU 152 1970 This British Standard,[.]
BRITISH STANDARD AUTOMOBILE SERIES BS AU 152:1970 CONFIRMED SEPTEMBER 1990 Specification for Rear marking plates for vehicles Confirmed February 2011 BS AU 152:1970 Foreword This British Standard has been prepared under the authority of the Automobile Industry Standards Committee of BSI at the request of the Ministry of Transport Its purpose is to provide a specification for rear marking plates for vehicles to be used in accordance with the appropriate Regulation in order to give following vehicles adequate warning, both by day and by night, of particular types or lengths of vehicles which might constitute a hazard 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 This British Standard, having been approved by the Automobile Industry Standards Committee, was published under the authority of the Executive Board of the Institution on 30 April 1970 © BSI 02-2000 The following BSI references relate to the work on this standard: Committee reference AUE/1 Draft for comment 69/10282 ISBN 580 06160 Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages to 12, an inside back cover and a back cover This standard has been updated (see copyright date) and may have had amendments incorporated This will be indicated in the amendment table on the inside front cover Amendments issued since publication Amd No Date Comments BS AU 152:1970 Contents Page Foreword Inside front cover Scope Definitions Design Type test Marking Materials Preparation and finish of plates Reflex — reflecting and fluorescent surfaces Letters and borders 10 Adhesive marking plates 11 Colour 12 Photometric requirements 13 Accelerated weathering 14 Bending and corrosion 15 Fuel resistance 16 Bonding strength 17 Water resistance 18 Thermal resistance 19 Abrasion resistance 20 Attachment of marking plates to the vehicle with adhesive 21 Attachment of individual letters and borders by adhesive 22 Rigidity of suspended marking plates Appendix A Terms and symbols relating to reflex-reflecting devices Appendix B Apparatus and method for accelerated weathering test Figure — Explanatory diagram of symbols used Figure — Types of rear marking plates Figure — Apparatus for accelerated weathering test: assembled views 10 Figure — Apparatus for accelerated weathering test: details of spray nozzles 11 Figure — Arrangements for measurement of reflective intensity of wet reflectorized test specimens 12 Table — Reflex-reflecting material: chromaticity limits Table — Fluorescent material: colour limits before and after weathering Table — Minimum CIL per square metre of reflex-reflecting surfaces in candelas per lux © BSI 02-2000 i ii blank BS AU 152:1970 Scope This British Standard specifies requirements for marking plates faced with reflex-reflecting and fluorescent materials for fitting to the rear of certain vehicles and trailers The standard includes requirements for colorimetric and photometric properties and tests for certain physical requirements Definitions For the purposes of this British Standard the following definitions, together with those given in Appendix A, apply: 2.1 rear marking plate a rectangular backing plate faced with reflex-reflecting and fluorescent materials and, where appropriate, letters, as prescribed in this specification NOTE The direct attachment with adhesive of reflex-reflecting and fluorescent materials only to the vehicle does not constitute a rear marking plate for the purposes of this British Standard 2.2 sample unit a complete rear marking plate, as used NOTE Photometric units such as lumen (lm), candela (cd), etc., are as defined in BS 233, “Glossary of terms used in illumination and photometry” Design 3.1 Dimensions Five types of rear marking plates are specified, as shown in Figure NOTE Except for the mounting position on the vehicle, Types and are identical The dimensions of the plates and of the reflex-reflecting and fluorescent areas and the proportions of the letters shall be as prescribed or otherwise authorized in the appropriate Regulation 3.2 Stiffening When rear marking plates are to be freely suspended from a vehicle they shall be stiffened either by flanges integral with the plate and forming part of it, or by means of a separate stiffening structure Such separate stiffening need not be included in the sample unit for the purpose of the bending and corrosion test in Clause 14 Rear marking plates that have been stiffened shall comply with the requirements of Clause 22 Type test Representative sample units shall be submitted to an independent testing authority for type testing © BSI 02-2000 The number of sample units to be selected for testing shall be agreed between the manufacturer and the testing authority but will normally comprise not less than two representative samples of Types 1, or 3, two of Type and two of Type All the sample units submitted shall comply with all the requirements in this standard Marking Each rear marking plate shall be permanently and legibly marked, in such a position as to be clearly visible when the marking plate is fitted to the vehicle, with the following information: 1) The name, trade mark or other means of identification of the maker 2) The number of this British Standard, i.e BS AU 152 NOTE Attention is drawn to certification facilities offered by BSI; see the inside back cover of this standard Materials Rear marking plates may be manufactured from any suitable material which shall perform satisfactorily in service and satisfy the requirements of this standard Preparation and finish of plates Before the application of the reflex-reflecting and the fluorescent surfaces, the surface of the backing plate shall be free from grease, oil, dirt and any loose or temporary coatings and shall be suitable for and adequate to receive the materials to be applied Reflex-reflecting and fluorescent surfaces 8.1 Any material may be used for the reflex-reflecting and the fluorescent areas or borders provided that it is applied so as to give the appearance of a continuous surface and that it complies with all the relevant requirements of this standard 8.2 Where holes are pierced for fixing the rear marking plate to the vehicle or for attaching letters to the marking plate, such holes shall be adequately-protected against any deleterious effect on the applied surface material Where, after the marking plate has left the maker’s works, it may be pierced with holes which can have a subsequent deleterious effect on the reflex-reflecting or fluorescent material, the marking plate maker shall attach to each plate a label giving adequate instructions for suitably fixing the plate to the vehicle in order to prevent such deleterious effect BS AU 152:1970 Letters and borders Letters and borders shall be securely attached to the rear marking plate so that they cannot be readily detached therefrom 10 Adhesive marking plates Where a rear marking plate is intended to be attached to the vehicle with adhesive, the marking plate maker shall give adequate instructions for the preparation of the surface to which it is to be attached and shall state the materials or surfaces for which the attachment of his marking plate is unsuitable 11 Colour 11.1 The colour of the reflex-reflecting material, the fluorescent material and the letters shall be as indicated in Figure 2, as appropriate 11.2 Reflex-reflecting material 11.3 Fluorescent material The fluorescent material, when illuminated by CIE Standard Illuminant C2) under the condition of normal incidence ± 10° and viewed at 45°, shall have a dominant wavelength, purity and luminance factor in accordance with the values given in Table NOTE The luminance factor includes both the reflected and the fluorescent luminous flux 11.4 Letters The letters on the Types and rear marking plates shall be black in colour and when illuminated normally by CIE Standard Illuminant C2) and viewed at 45° they shall have a maximum luminance factor of % 12 Photometric requirements The coefficient of luminous intensity (CIL) of the reflex-reflecting surfaces of the marking plate, when illuminated by CIE Standard Illuminant A3), shall be measured for each of the observation angles and the entrance angles ả specified in Table The CIL at any of the test points in Table at the 2° observation angle shall not exceed 150 cd/lx For making the necessary measurements, either of the methods recommended by the CIE or the Road Research Laboratory4) for the photometry of reflex-reflecting surfaces shall be used The normal axis to the plate shall be taken as the H-V direction The plate shall not be rotated and all measurements shall be made for & = 0° The angular subtense values ắ and shall not exceed 5ẵ 11.2.1 When the yellow reflex-reflecting surface is illuminated by CIE Standard Illuminant A1), with an observation angle of %° and an entrance angle V = ± 5°, H = 0°, the chromaticity values shall be within the area on the chromaticity diagram defined in Table The colour shall have chromaticity co-ordinates which lie within the area formed by the straight lines defined by the pairs of points and 2; and 3; and 4; and the spectrum locus 11.2.2 When the yellow reflex-reflecting surface is illuminated by CIE Standard Illuminant C2) under NOTE An explanation of the terms and symbols used is given the condition of normal incidence ± 10° and viewed in Appendix A at 45°, the luminance factor shall be 29 % and 39 % max Table — Reflex-reflecting material: chromaticity limits Colour Chromaticity co-ordinates of points at the corners of the area on the chromaticity diagram Co-ordinate Yellow 0.538 0.460 x y 0.520 0.460 0.560 0.420 0.579 0.420 Table — Fluorescent material: colour limits before and after weathering Exposure Dominant wavelength Min Max nm Unexposed 300 hours’ exposure 610 600 Excitation purity Min nm 617 — Min % 95 92 1) As defined in the proceedings of the 1951 meeting of the International 2) As defined in the proceedings of the 1931 meeting of the International 3) As defined in the proceedings of the 1951 meeting of the International 4) See Road Research Technical Paper No 42, “Reflex reflectors” Luminance factor Max % 31 — % — 60 Commission on Illumination (CIE) Commission on Illumination (CIE) Commission on Illumination (CIE) © BSI 02-2000 BS AU 152:1970 Table — Minimum CIL per square metre of reflex-reflecting surfaces in candelas per lux Entrance angle ¶ Colour Observation angle µ Vertical: H H H Horizontal: 5° left and 5° right 30° left and 30° right 45° left and 45° right cd/lx Yellow 0° 12½ 2° 18 13 Accelerated weathering 13.1 Procedure For each test two identical specimens of a sample unit (see Clause 2) are taken One specimen shall be stored in the dark in a dry container for subsequent use as the “reference unexposed specimen” The second specimen shall be exposed for 200 hours to an atmospheric weathering test using the apparatus and the method described in Appendix B After the test the specimen shall be washed in a dilute neutral detergent solution and examined for compliance with the requirements specified in 13.2 to 13.5 inclusive 13.2 Visual appearance No area of the exposed specimen shall show any evidence of cracking, scaling, pitting, blistering, de-lamination, distortion, blooming, staining, corrosion or chalking There shall be no shrinkage in excess of 0.5 % in any linear direction and no evidence of any adhesion failure such as edge lifting from the substrate 13.3 Colour fastness 13.3.1 Reflex-reflecting material The colour of the exposed specimen when compared with that of the “reference unexposed specimen” (see 13.1) shall have a fastness rating of not less than when measured by the Geometric Grey Scale in BS 26625) 13.3.2 Fluorescent material After exposure for 300 hours to an atmospheric weathering test, using the apparatus and method described in Appendix B and washing as in 13.1, the specimen shall be examined for compliance with 13.2 In addition, when illuminated by CIE Standard Illuminant C6) under the condition of normal incidence ± 10° and viewed at 45°, any shift in dominant wavelength and change in purity and luminance factor shall be such that the values are within the limits given in Table cd/lx 0.75 cd/lx 2.5 0.4 13.4 Effect on CIL value of reflex-reflecting material 13.4.1 For this test, measurements shall be made only at an entrance angle of 5° and an observation angle of 0° 12½ by the method given in Clause 11 13.4.2 The CIL of the exposed specimen when dry shall be not less than 80 % of the relevant value in Table 13.4.3 The specimen shall then be subjected to a fine water spray using the apparatus shown in Figure and kept continuously wetted The CIL of the specimen under this condition shall be not less than 90 % of the value obtained when measured dry in 13.4.2 13.5 Effect of dirt on reflex-reflecting material 13.5.1 The tests shall be made using the same exposed specimen and after the tests described in 13.4 13.5.2 The dry specimen shall first be artificially dirtied by the application of a layer of graphite grease thick enough to obscure the face of the specimen The layer of grease shall then be removed by washing with a clean mixture of water and a neutral detergent A soft bristle brush may be used to assist in the removal of the dirt, if necessary 13.5.3 The specimen shall then be tested in accordance with Clauses 11 and 12 and shall comply with the following requirements: 1) The luminance factor shall be not less than 80 % of the minimum value specified in 11.2.1 2) The CIL value at an entrance angle of 5° and an observation angle of 0° 12½ shall be not less than 80 % of the relevant minimum value specified in Table 5) BS 2662, “Grey scale for assessing change in colour” (contained in BS 2661-86 & BS 3661, “Methods for the determination of the colour fastness of textiles”) 6) As defined in the proceedings of the 1931 meeting of the International Commission on Illumination (CIE) © BSI 02-2000 BS AU 152:1970 14 Bending and corrosion (See 3.2) 17 Water resistance 14.1 Bending In the case of marking plates constructed solely, excluding the letters, from all-metal back-plates laminated with reflex-reflecting and fluorescent materials, a sample unit with, where appropriate, representative letters attached shall be bent around a 50 mm diameter mandrel to an included angle of 90° and then flattened Failure or detachment of the letters, where fitted, shall not constitute failure of the sample unit 14.2 Corrosion resistance The bent and flattened portion of the sample unit shall then be subjected to the action of a saline mist for 50 hours, comprising two periods of exposure of 24 hours each, separated by an interval of hours during which the specimen is allowed to dry The saline mist shall be produced by atomizing, at a temperature of 35 ± °C, a saline solution obtained by dissolving 20 ± parts by weight of sodium chloride in 80 parts of distilled water containing not more than 0.02 % of impurities 14.2.1 Immediately after completion of the test the sample shall not show signs of corrosion liable to impair the efficiency of the device 14.2.2 The CIL of the reflex-reflecting surfaces, when tested as specified in Clause 12, shall be not less than those given in Table 17.1 A section of a specimen not less than 300 mm long shall, except for the cut edge, be immersed in water for a period of 20 hours, after which it shall be removed and allowed to dry for hours This test shall be repeated four times 17.2 After completion of this test cycle the section shall be examined No part shall show evidence of deterioration which would reduce the effectiveness of the marking plate 15 Fuel resistance 15.1 A section of a sample unit not less than 300 mm long shall, except for the cut edge, be immersed in a mixture of petrol and benzene (proportion 90 : 10) for minutes and then removed 15.2 After a further minutes the section shall be examined Other than local surface crazing, it shall not show any visible change 16 Bonding strength 16.1 Where reflex-reflecting or fluorescent surfaces are laminated or coated to background materials the adhesion shall be determined in accordance with Appendix H in BS 873:19597) 16.2 When tested by this method the load required to produce failure shall be not less than 440 N 7) BS 873, “The construction 8) See BS 410, “Test sieves” 18 Thermal resistance 18.1 A section of a sample unit not less than 300 mm long shall be kept for 12 consecutive hours in a dry atmosphere at a temperature of 65 ± °C, after which it shall be kept for 20 hours at a temperature of minus 40 ± °C 18.2 After this test, no cracking or appreciable distortion of the surfaces, particularly of the optical units, shall be evident 18.3 The optical performance shall then be checked and shall comply with the requirements of Clauses 11 and 12 19 Abrasion resistance 19.1 The outer surfaces of the reflective background or covering material shall be rubbed by hand for minute using medium pressure with a linen pad and dry quartz powder of nominal sieve aperture size 53 Èm8) and then washed and dried 19.2 The CIL value of the area so treated shall then be determined and shall not fall below 80 % of the relevant value in Table 19.3 There shall be no visual evidence of damage to the surface coating which would impair the protective function of that coating 20 Attachment of marking plates to the vehicle with adhesive Marking plates designed to be attached to the vehicle with adhesive shall comply with the requirements of Clause 16 For the test, the marking plate shall be applied by the inspecting authority to a surface representative of that to which the marking plate may be applied on a vehicle (see Clause 10) The test shall be carried out at a temperature of 25 ± °C after the marking plate has been attached to the surface for a period of between 48 hours and 72 hours of road traffic signs and internally illuminated bollards” © BSI 02-2000 BS AU 152:1970 21 Attachment of individual letters and borders by adhesive 22 Rigidity of suspended marking plates 21.1 Where individual letters and borders are to be attached to the marking plate by adhesive, sample letters and portions of the borders attached to the marking plate using the adhesive supplied by the marking plate manufacturer shall be subjected to the test specified in Clause 16 21.2 When tested by this method the load required to produce failure shall be not less than 440 N multiplied by the ratio of the area of the samples tested to that specified in Appendix H in BS 873:19599) 22.1 The marking plate shall be placed on two supports in such a way that the supports are parallel to the shorter edges of the plate, and the distance from either support to the adjacent edge of the plate shall not exceed L/10 where L is the greater overall dimension of the plate The plate shall be loaded by means of bags of shot or bags of dry sand to a uniformly distributed pressure of 1.5 kN/m2 (15 mbar) The deflection of the plate shall be measured at a point mid-way between the supports 22.2 When tested as described in 22.1 the maximum deflection of the plate under the test load shall not exceed one-fortieth of the distance between the supports in 22.1 and the residual deflection after removal of the load shall not exceed one-fifth of the measured deflection under load 9) BS 873, “The construction of road traffic signs and internally illuminated bollards” © BSI 02-2000 BS AU 152:1970 Appendix A Terms and symbols relating to reflex-reflecting devices A.1 Terms 1) Reflex reflection Reflection in which light is reflected in directions close to the direction from which it came This property is maintained over wide variations of the entrance angle 2) Reflex-reflecting optical unit A combination of optical components producing reflex reflection 3) Reflex-reflecting device An assembly ready for use and comprising one or more reflex-reflecting optical units 4) Effective reflex surface That part of the surface of a reflex-reflecting device which is occupied by an assembly of reflex-reflecting optical units and which appears continuous at the normal observation distances 5) Reference axis The axis, as defined by the manufacturer of the reflex-reflecting device, which serves as reference direction for the entrance angles in photometric measurements and in practical use The reference axis usually corresponds to the axis of symmetry, if any, of the effective reflex surface 6) Reference centre The orthogonal projection of the centre of gravity of the effective reflex surface on the plane nearest to the observer which is tangential to that surface and perpendicular to the reference axis of the reflex-reflecting device 7) Observation angle The angle between the straight lines connecting the reference centre to the centre of the receiver and to the centre of the source of illumination 8) Entrance angle The angle between the reference axis and the straight line connecting the reference centre to the centre of the source of illumination 9) Rotation angle The angle through which the reflex-reflecting device is rotated about its reference axis starting from one given position 10) Angular subtense of the reflex-reflecting device The angle subtended by the greatest dimension of the visible area of the effective reflex surface from a specified reference point 11) Illumination at the reflex-reflecting device The illumination measured at the reference centre in a plane perpendicular to the incident rays and passing through the reference centre 12) Coefficient of luminous intensity (CIL) The value obtained by dividing the luminous intensity reflected in the direction considered by the illumination of the reflex-reflecting device, for given observation, entrance and rotation angles 13) Colour The colour of the light reflected by the reflex-reflector, defined in terms of its chromaticity co-ordinates, using the trichromatic system recommended by the International Commission on Illumination (CIE) in 1931 In this system the colour is expressed in the chromaticity co-ordinates x, y and z, the sum of which is unity The co-ordinate x is an indication of the proportion of red, y of the proportion of green and z of the proportion of blue 14) Chromaticity The colour quality of the light defined in terms of its chromaticity co-ordinates 15) Uncoloured light White light reflected from the outer surface of a reflex-reflector 16) Colour temperature The absolute temperature on the Kelvin scale (degrees K) of a full radiator, the colour of which is as nearly as possible identical with the colour of the white light source A.2 Symbols (see Figure 1) A C NC Rr Cr Ìr Se Cs Ìs = = = = = = = = = Area of the effective reflex surface of the reflex-reflecting device Reference centre Reference axis Receiver, observer or measuring device Centre of receiver Diameter of receiver Rr, if circular Source of illumination Centre of source of illumination Diameter of source of illumination © BSI 02-2000 BS AU 152:1970 De = Distance from centre Cs to centre C D½e = Distance from centre Cr to centre C NOTE De and D½e are generally very nearly the same and under normal conditions of observation it may be assumed that De = D½e Furthermore, the effective distances may be used when a collimated system is used in order to obtain an artificially increased measuring distance = Observation angle = Entrance angle With respect to the line Cs-C which is always considered to be horizontal, this angle is prefixed with signs – (left), + (right), + (up) or + (down), according to the position of the source Se in relation to the axis NC, as seen when looking towards the reflex-reflecting device For any direction defined by two angles, vertical and horizontal, the vertical angle is always given first r = Angular subtense of the measuring device Rr as seen from point C ¸ = Angular subtense of the source Se as seen from point C ¼ = Rotation angle This angle is positive when the rotation is clockwise as seen when looking towards the illuminated surface If the reflex-reflecting device is marked “TOP”, the position thus indicated is taken as the origin E = Illumination of the reflex-reflecting device CIL = Coefficient of luminous intensity ả Figure Explanatory diagram of symbols used Appendix B Apparatus and method for accelerated weathering test B.1 Apparatus (see Figure and Figure 4) The apparatus shall consist of: 1) A drum, approximately 1.22 m in diameter, capable of rotating about its axis, which is vertical Within the drum are normally three galleries for mounting the specimens under test The galleries have provision for draining 2) A lid, fitted over the top of the drum, but not rotating with it The lid is so arranged that it may be raised or lowered for the purpose of adjusting the temperature of the air within the drum 3) A black panel thermometer unit mounted in a suitable frame for attachment to the galleries such that it is held in the same position and at the same distance from the area as the test specimens © BSI 02-2000 BS AU 152:1970 4) Twin arc lamps, mounted diametrically opposite with their axes vertical and between 180 mm and 230 mm from the axis of the drum The arcs are formed between two uncored or neutral core carbons, each 14 ± mm diameter, enclosed in clear borosilicate glass enclosures The glass enclosures shall be as airtight as possible and shall be replaced after approximately 000 hours’ use or whenever pronounced discoloration or milkiness develops, whichever occurs first The supply to each arc shall be maintained between 130 volts and 145 volts and 15 amperes and 17 amperes 5) An assembly of water atomizers by means of which the specimens are sprayed with fresh distilled water Each atomizer discharges approximately 1.7 litres per hour with an air pressure of approximately N/m2 (0.05 mbar), in such a way that the whole of the surface of each specimen is evenly wetted with a fine mist In storage and in passage to the atomizers, the water shall not come into contact with any material other than stainless steel, glass, polymethyl methacrylate or polythene10) The water used shall be fresh and not recirculated, shall have a pH value between 6.0 and 8.0, shall have a total solid content of not more than 50 parts per million, including a copper content of not more than 0.2 parts per million, and shall enter the atomizer assembly at a temperature between 10 °C and 20 °C B.2 Method of test B.2.1 A suitably sized portion of a sample unit shall be conditioned for 48 hours at 20 ± °C The portion shall then be cut into two identical specimens, each not less than 100 cm2 in area, and the cut edges sealed by means appropriate to the materials One specimen piece is placed in a dry, dark contained as a “reference unexposed specimen” The other is mounted on one of the galleries of the drum The drum is rotated at a speed not greater than 60 rev/h nor less than 10 rev/h, so that the specimen is exposed to 102 minutes of continuous light followed by 18 minutes of light and water in any two hour period B.2.2 During this time the height of the lid is regulated so that the black panel thermometer reads 63 ± °C when the thermometer is at the point on the periphery where maximum heat is produced as the galleries rotate round the arcs For one hour in 24 hours the specimen is removed from the gallery and placed in cold storage in a chamber maintained at a temperature between minus 15 °C and minus 20 °C During this period the carbons are adjusted or replaced and the arc glass enclosures cleaned The specimen is replaced in different galleries in turn to ensure uniform exposure to the arc The above cycle shall be maintained for days continuously, and the specimen remains undisturbed for the remaining days of the week B.2.3 The test is continued for a total exposure period of 200 hours 10) It should be noted that the name “polythene” is equivalent to the name “polyethylene” © BSI 02-2000 BS AU 152:1970 Figure — Types of rear marking plates © BSI 02-2000 BS AU 152:1970 Figure — Apparatus for accelerated weathering test: assembled views 10 © BSI 02-2000 BS AU 152:1970 Figure — Apparatus for accelerated weathering test: details of spray nozzles © BSI 02-2000 11 BS AU 152:1970 Figure — Arrangements for measurement of reflective intensity of wet reflectorized test specimens 12 © BSI 02-2000 BS AU 152:1970 BSI Certification Trade Mark (The Kitemark) The British Standards Institution is the owner of a registered certification trade mark It is usually associated with the words “approved to British Standard” as shown below, the number of the relevant British Standard being added This mark may be used only by those licensed under the certification mark scheme operated by BSI The presence of this mark 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