Tyres shall be classified as follows:

(a) class C1 tyres

tyres designed primarily for vehicles of categories M₁, N₁, O₁ and O₂;

(b) class C2 tyres

tyres designed primarily for vehicles of categories M₂, M₃, N, O₃ and O₄ with a load capacity index in single formation ≤ 121 and the speed category symbol ≥ ‘N’;

(c) class C3 tyres

tyres designed primarily for vehicles of categories M₂, M₃, N, O₃ and O₄ with one of the following load capacity indices:

1. (i)

   a load capacity index in single formation ≤ 121 and the speed category symbol ≤ ‘M’;

2. (ii)

   a load capacity index in single formation ≥ 122.

A tyre may be classified in more than one class provided that it meets all the relevant requirements of each class in which it is classified.

The list of load-capacity indices and their corresponding masses contained in UNECE Regulations 30 and 54 shall apply.