Winter tyre markings
The Snowflake symbol indicates that the tyre grips even under difficult conditions. Nokian Heavy Tyres recommends that winter tyres be used on all axles of heavy vehicles under demanding driving conditions. Good winter grip is also very important on the trailer. Trailer tyres are commonly neglected despite the fact that over 50 % of the weight of the tractor-trailer combination is on the trailer.
All of the Nokian Hakkapeliitta Truck and Nokian Hakka Truck tyres that have been designed for trucks and buses have received the official snow grip approval, the Snowflake symbol (3PMSF). This marking was previously used only for passenger car tyres, and it signifies that the tyre is officially approved for winter use. In order to achieve this approval, the tyres are tested with the snow acceleration method.
The Snowflake symbol requires verified winter safety
Tyres that receive the official snow grip marking, i.e. the Snowflake symbol, provide verified safety for demanding snow conditions. The traditional definition of a winter tyre is stated in the European ECE regulation 117.02. The definition states that the tyre's tread pattern, tread material, or structure must be primarily designed in order to provide it with better characteristics than ordinary tyres in terms of acceleration, traction, and stopping under demanding winter conditions.
A new feature is that the winter grip of a tyre intended for snowy conditions must be verified; receiving the label requires an officially approved snow acceleration test where the winter tyre is at least 25 % better than the reference tyre. The snow acceleration test is used because it has good discrimination and provides results that are easy to compare. The test brings out the snow grip properties of different tyres in the best possible way, but excludes the ice grip properties.