UN R54 change reports — Tyres for commercial vehicles and their trailers

00 series

• 00 series — Supplement 28

  Under paragraph 2.21., the nominal rim diameter is expressed either by codes (numbers below 100) or in millimetres (numbers above 100) but not both.

• 00 series — Supplement 27

  For tyres identified by the "tyre to rim fitment configuration" symbol "A", new paragraph 6.1.4.2.1. sets the maximum overall width in the lower area. It equals the nominal width of the mounting rim, as shown by the manufacturer in the descriptive note, increased by 38 mm. Before, paragraph 6.1.4.3. gave the overall width in the lower area as the rim width increased by 27 mm.

• 00 series — Supplement 26

  New paragraph 4.1.6.1. says that the speed category symbol E can be used only for the additional service description. In paragraph 2.31.2., symbol E corresponds to 70 km/h.

• 00 series — Supplement 25

  The markings now give the service description, and one additional service description surrounded by a circle in case paragraph 6.2.5. is applied.

• 00 series — Supplement 24

  The markings and the approval mark no longer need to be moulded on to or into the tyres (para. 3.4.). They must be clearly legible, indelible and raised above or sunk below the tyre surface.

• 00 series — Supplement 23

  For tyres intended for dual mounting (twinning), paragraph 6.1.4.2. now gives width tolerances in a table: 2% or 4% for the tyres it lists.