Document ID: chunk:federal_register_of_legislation:F2024C00148:reg:12:p7
Version: federal_register_of_legislation:F2024C00148
Segment Type: reg
Provision Reference: reg 12 (pt 7/24)
Character Range: 249128–251768

be such that:
7.1.2.1. In the case of circular mirrors, the diameter shall not be greater than 150 mm,
7.1.2.2. In the case of non‑circular mirrors, the reflecting surface shall fit into a rectangle measuring 120 mm by 200 mm.
7.2. Reflecting surface and coefficient of reflection
7.2.1. The reflecting surface of a rear‑view mirror shall be spherically convex.
7.2.2. Differences between the radii of curvature:
7.2.2.1. The difference between ri or r'i and rp at each reference point shall not exceed 0.15 r.
7.2.2.2. The difference between any of the radii of curvature (rp1, rp2 and rp3) and r shall not exceed 0.15 r.
7.2.3. The value of "r" shall not be less than 1,000 mm nor greater than 1,500 mm.
7.2.4. The value of the normal coefficient of reflection, determined according to the method described in annex 5 to this Regulation, shall not be less than 40%.  If the mirror has two positions ("day" and "night"), the "day" position shall allow the colours of the signals used for road traffic to be recognized.  The value of the normal coefficient of reflection in the "night" position shall not be less than 4%.
7.2.5. The reflecting surface shall retain the characteristics specified in paragraph 7.2.4., in spite of prolonged exposure to adverse weather conditions, in normal conditions of use.
8.  Tests
8.1. Rear‑view mirrors shall be subjected to the tests described in  paragraphs 8.2. and 8.3. below, to determine their behaviour under impact on and bending of the holder secured to the stem or support.
8.2. Impact test
8.2.1. Description of the test device:
8.2.1.1. The test device shall consist of a pendulum capable of swinging about two horizontal axes at right angles to each other, one of which is perpendicular to the front plane containing the "release" trajectory of the pendulum.  The end of the pendulum shall comprise a hammer formed by a rigid sphere with a diameter of 165 + 1 mm and having a 5 mm‑thick rubber covering of Shore A 50 hardness.  A device shall be provided which permits determination of the maximum angle assumed by the arm in the plane of release.  There shall be a support firmly fixed to the structure supporting the pendulum which serves to hold the specimens in compliance with the impact requirements stipulated in paragraph 8.2.2.6. below.  Figure 1 below gives the dimensions of the test facility and the special design specifications.
8.2.1.2. The centre of percussion of the pendulum shall coincide with the centre of the sphere which forms the hammer.  It is at a distance "1" from the axis of oscillation in the release plane which is equal to 1 m +5 mm.  The reduced mass of the