41997X0730(02)

Technical requirements of Regulation No 3 of the United Nations' Economic Commission for Europe referred to in Article 3 and in Annex II, item 2.1 of Commission Directive 97/29/EC (1) adapting to technical progress Council Directive 76/757/EEC relating to retro-reflectors for motor vehicles and their trailers

2. DEFINITIONS (2)

For the purpose of this Regulation,

2.1. The definitions given in Regulation No 48 and its series of amendments in force at the time of application for type approval shall apply to this Regulation.

2.2. 'Retroreflection` means the 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 illumination angle.

2.3. 'Retroreflecting optical unit` means a combination of optical components producing retroreflection.

2.4. 'Retroreflecting device` (3) means an assembly ready for use and comprising one or more retroreflecting optical units.

Note:

2.5. 'Angle of divergence` means the angle between the straight lines connecting the centre of reference to the centre of the receiver and to the centre of the source of illumination.

2.6. 'Illumination angle` means the angle between the axis of reference and the straight line connecting the centre of reference to the centre of the source of illumination.

2.7. 'Angle of rotation` means the angle through which the retroreflecting device is rotated about its axis of reference starting from one given position.

2.8. 'Angular diameter of the retroreflecting device` means the angle subtended by the greatest dimension of the visible area of the illuminating surface, either at the centre of the source of illumination or at the centre of the receiver.

2.9. 'Illumination of the retroreflecting device` is the abbreviated expression used conventionally to designate the illumination measured in a plane perpendicular to the incident rays and passing through the centre of reference.

2.10. 'Coefficient of luminous intensity (CIL)` means the quotient of the luminous intensity reflected in the direction considered, divided by the illumination of the retroreflecting device for given angles of illumination, divergence and rotation.

2.11. The symbols and units used in this Regulation are given in annex 1 to this Regulation.

2.12. A type of 'retroreflecting device` is defined by the models and descriptive literature submitted with the application for approval. Retroreflecting devices can be considered as belonging to the same type if they have one or more 'retroreflecting optical units` which are identical with those of the standard model, or if not identical are symmetrical and suitable for mounting one on the left and one on the right side of the vehicle, and if their other parts differ from those of the standard model only in ways not affecting the properties to which this Regulation applies.

2.13. Retroreflecting devices are divided into three classes according to their photometric characteristics: Class I A, Class III A and Class IV A.

6. GENERAL SPECIFICATIONS

6.1. Retroreflecting devices must be so constructed that they function satisfactorily and will continue to do so in normal use. In addition, they must not have any defect in design or manufacture that is detrimental to their efficient operation or to their maintenance in good condition.

6.2. The components of retroreflecting devices must not be capable of being easily dismantled.

6.3. Retroreflecting optical units may not be replaceable.

6.4. The outer surface of retroreflecting devices must be easy to clean. Hence it must not be a rough surface; any protuberances it may exhibit must not prevent easy cleaning.

6.5. For devices of Class IV A their means of fixation shall be such that they allow a stable and durable connection between the device and the vehicle.

7. SPECIAL SPECIFICATIONS (TESTS)

7.1. Retroreflecting devices must also satisfy the conditions as to dimensions and shape, and the colorimetric, photometric, physical and mechanical requirements set forth in annexes 5 to 11 and 13 to this Regulation. The test procedures are described in annex 4 (Class I A and Class III A) and annex 14 (Class IV A).

7.2. Depending on the nature of the materials of which the retroreflecting devices and, in particular, their optical units, are made, the competent authorities may authorize laboratories to omit certain unnecessary tests, subject to the express reservation that such omission must be mentioned under 'Remarks` on the form notifying approval.

(1) Also called 'retroreflector(s)`.

(2) OJ No L 171, 30. 6. 1997, p. 11.

(3) The definitions of the technical terms (excluding the ones in Regulation No 48) are those adopted by the International Commission on Illumination (CIE).

ANNEX 1

Retroreflecting device

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Retroreflectors Symbols

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Elevation

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ANNEX 4

Test procedure - Class I A and Class III A

1. The applicant shall submit for approval ten samples which shall be tested in the chronological order indicated in annex 12.

2. After verification of the general specifications (paragraph 6 of the Regulation) and the specifications of shape and dimensions (annex 5), the ten samples shall be subjected to the heat resistance test described in annex 10 to this Regulation and at least one hour after this test examined as to their colorimetric characteristics (annex 6) and CIL (annex 7) for an angle of divergence of 20' and an illumination angle V = H = 0° or if necessary, in the position defined in annex 7, paragraphs 4 and 4.1. The two retroreflecting devices giving the minimum and maximum values shall then be fully tested as shown in annex 7. These two samples shall be kept by the laboratories for any further checks which may be found necessary. The other eight samples shall be divided into four groups of two:

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3. After undergoing the tests referred to in the above paragraph, the retroreflecting devices in each group must have:

3.1. a colour which satisfies the conditions laid down in annex 6. This shall be verified by a qualitative method and, in case of doubt, confirmed by a quantitative method.

3.2. a CIL which satisfies the conditions laid down in annex 7. The verification shall be performed only for an angle of divergence of 20' and an illumination angle of V = H = 0° or, if necessary, in the position specified in annex 7, paragraphs 4 and 4.1.

ANNEX 5

Specifications of shape and dimensions

1. SHAPE AND DIMENSIONS OF RETROREFLECTING DEVICES IN CLASS I A

1.1. The shape of the illuminating surfaces must be simple, and not easily confused at normal observation distances, with a letter, a digit or a triangle.

1.2. The preceding paragraph notwithstanding, a shape resembling the letters or digits of simple form O, I, U or 8 is permissible.

2. SHAPE AND DIMENSIONS OF RETROREFLECTING DEVICES IN CLASS III A (see appendix to this annex)

2.1. The illuminating surfaces of retroreflecting devices in Class III A must have the shape or an equilateral triangle. If the word 'TOP` is inscribed in one corner, the apex of that corner must be directed upwards.

2.2. The illuminating surface may or may not have at its centre a triangular, non-retroreflecting area, with sides parallel to those of the outer triangle.

2.3. The illuminating surface may or may not be continuous. In any case, the shortest distance between two adjacent retroreflecting optical units must not exceed 15 mm.

2.4. The illuminating surface of a retroreflecting device shall be considered to be continuous if the edges of the illuminating surfaces of adjacent separate optical units are parallel and if the said optical units are evenly distributed over the whole solid surface of the triangle.

2.5. If the illuminated surface is not continuous, the number of separate retroreflecting optical units including the corner units shall not be less than four on each side of the triangle.

2.5.1. The separate retroreflecting optical units shall not be replaceable unless they consist of approved retroreflecting devices in Class I A.

2.6. The outside edges of the illuminating surfaces of triangular retroreflecting devices in Class III A shall be between 150 mm and 200 mm long. In the case of devices of hollow-triangle type, the width of the sides, measured at right angles to the latter, shall be equal to at least 20 per cent of the effective length between the extremities of the illuminating surface.

3. SHAPE AND DIMENSIONS OF RETROREFLECTING DEVICES IN CLASS IV A

3.1. The shape of the light emitting surfaces must be simple and not easily confused at normal observation distances with a letter, a digit or a triangle. However, a shape resembling the letters and digits of simple form, O, I, U and 8 is permissible.

3.2. The light emitting surface of the retroreflecting device must be at least 25 cm².

4. Compliance with the above specifications shall be verified by visual inspection.

Appendix

RETROREFLECTORS FOR TRAILERS - CLASS III A

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150 mm ≤ A ≤ 200 mm

B ≥ A 5

C ≤ 15 mm>END OF GRAPHIC>

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Note: These sketches are for illustration purposes only.

ANNEX 6

Colorimetric specifications

1. These specifications shall apply only to clear, red or amber retroreflecting devices.

1.1. Retroreflecting devices may consist of a combined retroreflecting optical unit and filter, which must be so designed that they cannot be separated under normal conditions of use.

1.2. The colouring of retroreflecting optical units and filters by means of paint or varnish is not permitted.

2. When the retroreflecting device is illuminated by ICI standard illuminant A, with an angle of divergence of ° and an illumination angle of V = H = 0°, or, if this produces a colourless surface reflection, an angle V = ±5°, H = 0°, the trichromatic coordinates of the reflected luminous flux must be within the following limits:

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2.1. In the case of red and amber, compliance with the colorimetric specifications shall be verified by a visual comparison test.

2.2. If any doubt remains after this test, compliance with the colorimetric specifications shall be verified by determining the trichromatic coordinates of the most doubtful sample.

3. Clear retroreflecting devices must not produce a selective reflection, that is to say, the trichromatic coordinates 'x` and 'y` of the standard illuminant 'A` used to illuminate the retroreflecting device must not undergo a change of more than 0.01 after reflection by the retroreflecting device.

3.1. This shall be verified by the visual comparison test indicated above, the control field being illuminated by a light source of which the trichromatic coordinates differ by 0.01 from that of standard illuminant A.

3.2. In case of doubt, the trichromatic coordinates for the most selective sample shall be determined.

ANNEX 7

Photometric specifications

1. When applying for approval, the applicant shall specify the axis of reference. This corresponds to the illumination angle V = H = 0° in the table of coefficients of luminous intensity (CIL).

2. For photometric measurements, only the illuminating surface contained within a circle of 200 mm diameter for Class I A shall be considered, and the illuminating surface itself shall be limited to 100 cm² though the surfaces of the retroreflecting optical units need not necessarily attain this area. The manufacturer shall specify the perimeter of the area to be used. In the case of Class III A and Class IV A, the whole of the illuminating surfaces shall be considered without limitation as to size.

3. CIL VALUES

3.1. Categories I A and III A

3.1.1. The CIL values for red retroreflecting devices must be at least equal to those in the table below, expressed in millicandelas per lux, for the angles of divergence and illumination shown.

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CIL values lower than those shown in the last two columns of the above table are not permissible within the solid angle having the reference centre as its apex and bounded by the planes intersecting along the following lines:

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3.1.2. CIL values for amber retroreflecting devices in Class I A must be at least equal to those in the table of paragraph 3.1.1. above multiplied by the coefficient 2.5.

3.1.3. CIL values for colourless retroreflecting devices in Class I A must be at least equal to those in the table of paragraph 3.1.1. above multiplied by the coefficient 4.

3.2. For devices of Class IV A the CIL values must be at least equal to those in the table below, expressed in millicandelas per lux, for the angles of divergence and illumination shown.

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4. When the CIL of a retroreflecting device is measured for an angle â of V = H = 0°, it shall be ascertained whether any mirror effect is produced by slightly turning the device. If there is any such effect, a reading shall be taken with an angle â of V = ±5°, H = 0°. The position adopted shall be that corresponding to the minimum CIL for one of these positions.

4.1. With an illumination angle â of V = H = 0°, or the angle specified in paragraph 4 above, and an angle of divergence of 20', retroreflecting devices which are not marked 'TOP` shall be rotated about their axes of reference to the position of minimum CIL, which must conform to the value specified in paragraph 3 above. When the CIL is measured for the other angles of illumination and divergence, the retroreflecting device shall be placed in the position corresponding to this value of å. If the specified values are not attained, the device may be rotated about its axis of reference ±5° from that position.

4.2. With an illumination angle â of V = H = 0°, or the angle specified in paragraph 4 above, and an angle of divergence of 20', retroreflecting devices marked 'TOP` shall be rotated about their axes ±5°. The CIL must not fall below the prescribed value in any position assumed by the device during this rotation.

4.3. If for the direction V = H = 0°, and for å = 0° the CIL exceeds the specified value by 50 per cent or more, all measurements for all angles of illumination and divergence shall be made for å = 0°.

ANNEX 8

Resistance to external agents

1. RESISTANCE TO PENETRATION OF WATER

1.1. Retroreflecting devices whether part of a lamp or not, shall be stripped of all removable parts and immersed for 10 minutes in water at a temperature of 50° ±5°C, the highest point of the upper part of the illuminating surface being 20 mm below the surface of the water. This test shall be repeated after turning the retroreflecting device through 180 °C, so that the illuminating surface is at the bottom and the rear face is covered by about 20 mm of water. These optical units shall then be immediately immersed in the same conditions in water at a temperature of 25° ±5°C.

1.2. No water must penetrate to the reflecting surface of the retroreflecting optical unit. If visual inspection clearly reveals the presence of water, the device shall not be considered to have passed the test.

1.3. If visual inspection does not reveal the presence of water or in case of doubt, the CIL shall be measured by the method described in annex 4, paragraph 3.2. or annex 14, paragraph 4.2., the retroreflecting device being first lightly shaken to remove excess water from the outside.

2. RESISTANCE TO CORROSION

2.1. Retroreflecting devices must be so designed that they retain the prescribed photometric and colorimetric characteristics despite the humidity and corrosive influences to which they are normally exposed. The resistance of the front surface to tarnishing and of the protection of the rear face to deterioration shall be checked, particularly when an essential metal component seems liable to be attacked.

2.2. The retroreflecting device, or the lamp if the device is combined with a light, shall be stripped of all removable parts and subjected to the action of a saline mist for a period of 50 hours, comprising two periods of exposure of 24 hours each, separated by an interval of two hours during which the sample is allowed to dry.

2.3. The saline mist shall be produced by atomizing, at a temperature of 35° ±2°C, a saline solution obtained by dissolving 20 ±2 parts by weight of sodium chloride in 80 parts of distilled water containing not more than 0.02 per cent of impurities.

2.4. Immediately after completion of the test, the sample must not show signs of excessive corrosion liable to impair the efficiency of the device.

3. RESISTANCE TO FUELS

The outer surface of the retroreflecting device and, in particular, of the illuminating surface, shall be lightly wiped with a cotton cloth soaked in a mixture of 70 vol. per cent of n-heptane and 30 vol. per cent of toluol. After about five minutes, the surface shall be inspected visually. It must not show any apparent surface changes, except that slight surface cracks will not be objected to.

4. RESISTANCE TO LUBRICATING OILS

The outer surface of the retroreflecting device and, in particular, the illuminating surface, shall be lightly wiped with a cotton cloth soaked in a detergent lubricating oil. After about five minutes, the surface shall be cleaned. The CIL shall then be measured (annex 4, paragraph 3.2. or annex 14, paragraph 4.2.).

5. RESISTANCE OF THE ACCESSIBLE REAR FACE OF MIRROR-BACKED RETROREFLECTING DEVICES

5.1. After having brushed the rear face of the retroreflecting device with a hard nylon brush, a cotton cloth soaked in the mixture, defined in paragraph 3 shall be applied to the said rear face for one minute. The cotton cloth is then removed and the retroreflecting device left to dry.

5.2. As soon as evaporation is completed, an abrasion test shall be made by brushing the rear face with the same nylon brush as before.

5.3. The CIL shall then be measured (annex 4, paragraph 3.2. or annex 14, paragraph 4.2.) after the whole surface of the mirror-backed rear face has been covered with Indian ink.

ANNEX 9

Stability in time of the optical properties of retroreflecting devices (1)

1. The authority which granted approval shall have the right to check the stability in time of the optical properties of a type of retroreflecting device in service.

2. The competent authorities of countries other than the country in which approval was granted may carry out similar checks in their territory. If a type of retroreflector in use exhibits a systematic defect, the said authorities shall transmit any components removed for examination to the authority which granted approval, with a request for its opinion.

3. In the absence of other criteria, the concept of 'systematic defect` of a type of retroreflector in use shall be interpreted in conformity with the intention of paragraph 6.1. of this Regulation.

Note:

(1) Despite the importance of tests to check the stability in time of the optical properties of retroreflecting devices, it is in the present state of the art not yet possible to assess this stability by laboratory tests of limited duration.

ANNEX 10

Resistance to heat

1. The retroreflecting device shall be kept for 48 consecutive hours in a dry atmosphere at a temperature of 65 ±2°C.

2. After this test, no cracking or appreciable distortion of the retroreflecting device and, in particular, of its optical component must be visible.

ANNEX 11

Colour-fastness (1)

1. The authority which granted approval shall have the right to check the colour-fastness of a type of retroreflecting device in service.

2. The competent authorities of countries other than the country in which approval was granted may carry out similar checks in their territory. If a type of retroreflector in use exhibits a systematic defect, the said authorities shall transmit any components removed for examination to the authority which granted approval, with a request for its opinion.

3. In the absence of other criteria, the concept 'systematic defect` of a type of retroreflector in use shall be interpreted in conformity with the intention of paragraph 6.1. of this Regulation.

Note:

(1) Despite the importance of tests to check the colour-fastness of retroreflecting devices, it is in the present state of the art not yet possible to assess colour-fastness by laboratory tests of limited duration.

ANNEX 12

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ANNEX 13

Resistance to impact - Class IV A

1. The retroreflecting device shall be mounted in a manner similar to the way in which it is mounted on the vehicle, but with the lens faced horizontal and directed upwards.

2. Drop a 13 mm diameter polished solid steel ball, once, vertically onto the central part of the lens from a height of 0.76 m. The ball may be guided but not restricted in free fall.

3. When a retroreflecting device is tested at room temperature with this method, the lens shall not crack.

ANNEX 14

Test procedure - Class IV A

1. The applicant shall submit for approval ten samples which shall be tested in the chronological order indicated in annex 15.

2. After verification of the specifications in paragraphs 6.1. to 6.5. and the specifications of shape and dimensions (annex 5), the ten samples shall be subjected to the heat resistance test (annex 10) and one hour minimum after this test examined as to their colorimetric characteristics (annex 6) and CIL (annex 7) for an angle of divergence of 20' and an illumination angle V = H = 0° or, if necessary, in the positions defined in annex 7. The two retroreflecting devices giving the minimum and maximum values shall then be fully tested as shown in annex 7. These two samples shall be kept by the laboratories for any further checks which may be found necessary.

3. Four samples out of the remaining eight samples shall be selected at random and divided into two groups of two in each group.

First group:

The two samples shall be subjected successively to the water-penetration resistance test (annex 8, paragraph 1) and then, if this test is satisfactory, to the tests for resistance to fuels and lubricating oils (annex 8, paragraphs 3 and 4).

Second group:

The two samples shall, if relevant, be subjected to the corrosion test (annex 8, paragraph 2), and then to the abrasive-strength test of the rear face of the retroreflecting device (annex 8, paragraph 5). These two samples shall also be subjected to the impact test (annex 13).

4. After undergoing the tests referred to in the above paragraph, the retroreflecting devices in each group must have:

4.1. A colour which satisfies the conditions laid down in annex 6. This shall be verified by a qualitative method and, in case of doubt, confirmed by a quantitative method;

4.2. A CIL which satisfies the conditions laid down in annex 7. Verification shall be performed only for an angle of divergence of 20' and an illumination angle of V = H = 0° or, if necessary, in the positions specified in annex 7.

5. The four remaining samples can be utilized, if necessary, for any other purpose.

ANNEX 15

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