Document ID: chunk:federal_register_of_legislation:F2018L01518:reg:60:p5
Version: federal_register_of_legislation:F2018L01518
Segment Type: reg
Provision Reference: reg 60 (pt 5/12)
Character Range: 31860–34626

conspicuously to every tyre conforming to a type of tyre approved under this Regulation, in the space referred to in paragraph 3.2. above and in addition to the markings prescribed in paragraph 3.1. above, an international approval mark consisting of:

5.4.1. A circle surrounding the letter "E" followed by the distinguishing number of the country which has granted approval;[4]/

5.4.2. An approval number.

5.5. The approval mark shall be clearly legible and be indelible.

5.6. Annex 2 to this Regulation gives an example of the arrangement of the approval mark.

6. Requirements

6.1. Dimensions of tyres

6.1.1.  Section width of a tyre

6.1.1.1. The section width shall be calculated by the following formula:

 S = S1 + K (A-A1),

 where:

                  S is the "section width" rounded to the nearest millimetre and measured on the measuring rim;

                  S1 is the "nominal section width" (in mm) as shown on the side wall of the tyre in the designation of the tyre as prescribed;

                  A is the width (expressed in mm) of the measuring rim, as shown by the manufacturer in the descriptive note,[5]

 A1 is the width (expressed in mm) of the theoretical rim.

A1 shall be taken to equal S1 multiplied by the factor x, as specified by the manufacturer, and K shall be taken to equal 0.4.

6.1.1.2. However, for the types of tyres for which the designation is given in the first column of the tables in Annex 5 to this Regulation, the section width shall be that given opposite the tyre designation in these tables.

6.1.1.3. However, for tyres identified by the "tyre to rim fitment configuration" (see para. 3.1.13.) symbol "A" or "U", K shall be taken equal to 0.6.

6.1.2. Outer diameter of a tyre

6.1.2.1. The outer diameter of a tyre shall be obtained by means of the following formula:

  D = d + 2H

  where:

D is the outer diameter expressed in millimetres;

                  d is the nominal rim diameter defined in paragraph 2.23. above, expressed in millimetres;

                  H is the nominal section height rounded to the nearest millimetre and is equal to:

                  H = S1 • 0.01 Ra, where

                  S1 is the nominal section width in millimetres (mm);

                  Ra is the nominal aspect ratio;

all as shown on the sidewall of the tyre in the tyre-size designation in conformity with the requirements of paragraph 3.4. above.

6.1.2.2. However, for the types of tyres for which the designation is given in the first column of the tables of Annex 5 to this Regulation the outer diameter shall be that given opposite the "size" designation in these tables.6.1.2.3.

However, for tyres identified by the "tyre to rim fitment configuration" (see para. 3.1.13.) symbol "A" or "U",