The extension of UN R90 to include brake drums and discs introduced the concept of a part “identical” to the OE part. Because such parts would have been approved under UN R13/13-H, they were exempted from redundant approval under R90. This proposal would similarly define and exempt brake linings.

UN R90 unintentionally omits the bedding procedure for the brake drum high load test for M2, M3, N2 and N3 vehicles. CLEPA proposes using the same bedding procedure as already adopted for the thermal fatigue test for such vehicles and for the high load tests for trailers.