UN / ECE R 75 Tests

UN ECE R75 tests cover a series of tests carried out in accordance with the relevant regulation for the evaluation of new pneumatic tires for vehicles in categories L 1 , L 2 , L 3 , L 4 and L 5 .

ECE regulations define cross-border technical regulations for establishing approval or uniform approval procedures for motor vehicles and motor vehicle parts. Automated commercial vehicles are already fully eligible for approval only through appropriate individual measures in the country in which they will be used. What is missing is a set of rules at the international ECE level.

Regulation 75 of the United Nations Economic Commission for Europe (UN/ECE) — Covers the uniform provisions for the approval of pneumatic tires for motorcycles and mopeds and the tests applied accordingly.

This Regulation applies to new pneumatic tires for vehicles of categories L 1 , L 2 , L 3 , L 4 and L 5. However, it does not apply to tire types designed for 'off road' use only and marked 'NHS' (Not for Highway Service) and tire types designed for competitions only.

Pneumatic tire type means a category of pneumatic tires that do not differ in essential respects such as:

• Producer;
• Tire size definition;
• Usage category (normal: for normal highway service; special: for special applications on and off road, snow, moped);
• Structure (diagonal or cross-ply, cross-belted, radial);
• speed category;
• load capacity index;
• Tire section.

'Construction of a pneumatic tire' means the technical characteristics of the carcass of the tyre. The following structures of a pneumatic tire are particularly distinguished:

• The 'diagonal' or 'ply ply' describes a pneumatic tire structure in which the ply cords extend into the bead and are laid at alternating angles substantially less than 1° to the centerline of the tread (90).
• 'Inclined belt' describes a cross (pitch ply) type of pneumatic tire construction in which the carcass is bounded by a belt comprising two or more layers of substantially inextensible cord material arranged at alternating angles close to that of the carcass.
• 'Radial' describes a pneumatic tire structure wherein the ply cords extend into the bead and are laid essentially at 90° to the centerline of the tread, the carcass being stabilized by an essentially inextensible circumferential.
• 'Reinforced' describes a pneumatic tire construction in which the carcass is more resistant than the corresponding normal tire.

Within the scope of the regulation, many mechanical, dynamic and environmental tests are carried out as well as measurements for the approval of the relevant equipment. For tests to be considered successful, test results must meet regulatory requirements.