Amendments in the regulations for the maximum permitted number of studs in studded tyres

“The Government is strongly engaged in road safety and the simplification of regulations to the advantage of consumers. It is vital that all Norwegian road users have access to all studded tyres that are developed in order for them to be in a position to select the tyres that are best suited to the personal preference and use. For these reasons we are now proposing that the Norwegian regulations shall be amended to confirm with those of Sweden and Finland such that more studs will be permitted in studded tyres sold in Norway”, says Transport and Communications Minister Ketil Solvik-Olsen.

The Directorate of Public Roads is in the process of sending a proposal for new regulations for hearing relating to studded tyres for passenger cars, busses, commercial vehicles and trailers for these, as well as for mopeds and motorcycles. The proposal is to permit additional studs in tyres in order to bring the Norwegian regulations in conformity with the Swedish and Finnish regulations.

“Our wish is to amend the regulations so that we have fully harmonised Nordic regulations. For consumers the changes mean that it will be possible to purchase studded tyres in any of the countries and use them across national boundaries. It will also be a major advantage to manufacturers to be able to conform to fully harmonised regulations without having to develop tyres to conform specifically to deviating regulations. The change will also contribute to increased innovation that will ensure that in the future studded tyres will be both safer and more environmentally friendly”, says Solvik-Olsen.

Previous uncertainty about road surface wear and particulate matter

There has been some uncertainty about road surface wear and the production of airborne particulate matter that has prevented the Norwegian authorities in introducing the same regulations as those in force in Sweden and Finland where more studs per tyre are permitted. Recent research has shown that there is not necessarily direct causality between the number of studs, road surface wear and the production of particulate matter.

Under the current regulations the number of studs permitted for vehicles and trailers is differentiated with an absolute maximum number calculated on the basis of wheel dimension. The current regulations permit 90 studs for wheel dimensions up to and including 13 inches, 110 studs for wheel dimensions of 14 – 15 inches and 130 studs for wheel dimension from and including 16 inches.

The new regulations mean that the number of studs permitted will be calculated on the basis of the individual tyre’s rolling circumference, with up to 50 studs per meter rolling circumference permitted. As an example a tyre with a two-metre rolling circumference will be permitted to have a maximum of 100 studs, while a tyre with a 2.5 meter rolling circumference will be permitted to have a maximum of 125 studs.