Document ID: chunk:federal_register_of_legislation:F2018C00788:front:0:p6
Version: federal_register_of_legislation:F2018C00788
Segment Type: other
Provision Reference: 
Character Range: 17502–20367

walls of an inflated pneumatic tyre, excluding elevations due to labelling (marking), decoration or protective bands or ribs; 2/

         2.13.  "Overall width" means the linear distance between the outsides of the side walls of an inflated pneumatic tyre, including labelling (marking), decoration and protective bands or ribs; 2/

         2.14.  "Section height" means a distance equal to half the difference between the outer diameter of the tyre and the nominal rim diameter; 2/

         2.15.  "Nominal aspect ratio (Ra)" means the centuple of the number obtained by dividing the number expressing the section height in mm by the number expressing the nominal section width in mm;

         2.16. "Outer diameter" means the overall diameter of an inflated new pneumatic tyre; 2/

         2.17.  "Tyre-size designation" is

         2.17.1.  a designation showing:

         2.17.1.1. the nominal section width.  This width must be expressed in mm, except in the case of the types of tyre for which the size designation is shown in the first column of the tables in Annex 5 to this Regulation;

         2.17.1.2. the nominal aspect ratio except in the case of certain types of tyre, for which the size designation is shown in the first column of the tables in Annex 5 to this Regulation, or, depending on the tyre design type, the nominal outer diameter expressed in mm;

         2.17.1.3. a conventional number denoting the nominal rim diameter and corresponding to its diameter expressed either by codes (numbers below 100) or in millimetres (numbers above 100);

         2.17.1.4.                    the letter "T" in front of the nominal section width in case of T‑type temporary use spare tyres;
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2/ See explanatory figure.

         2.17.1.5. an indication of the tyre to rim fitment configuration when it differs from the standard configuration.

         2.18.  "Nominal rim diameter" means the diameter of the rim on which a tyre is designed to be mounted;

         2.19.  "Rim" means the support for a tyre-and-tube assembly, or for a tubeless tyre, on which the tyre beads are seated; 2/

         2.19.1.  "Tyre to rim fitment configuration" means the type of rim to which the tyre is designed to be fitted.  In the case of non-standard rims this will be identified by a symbol applied to the tyre, for example, "CT", "TR", "TD" or "A".

         2.20.  "Theoretical rim" means the notional rim whose width would be equal to x times the nominal section width of a tyre. The value of x shall be specified by the manufacturer of that tyre;

         2.21.  "Measuring rim" means the rim on which a tyre is required to be fitted for size measurements;

2.22.  "Test rim" means the rim on which a tyre is required to be fitted for testing;

2.23.  "Chunking" means the breaking away of pieces of rubber from the