Details on current regulations on the use of winter tires and snow chains
Not surprisingly, clarifications and/or interpretations of current winter equipment regulations are still required. Therefore we need to go back on the subject and recall some of the points of the current regulatory framework, and its developments, concerning tires, their inherent characteristics and use
In order to increase grip on snow-clad roads or in icy conditions, winter tires, snow studs and snow chains may be used. The use of winter tires or chains is mandatory where prescribed by a special sign (circular with blue background - art.122), by local highway authorities and in compliance with law 120/2010 amendment art. 6 of the Traffic Code and/or in any case where road conditions impose the use of winter gear, even outside the mandatory period going from November 15 to April 15, as specified by the Ministry of Transport.
Winter tires - Markings
Given that all tires intended for road use must be "approved" (marked "E" followed by a number indicating the country of approval), those destined for winter use and in accordance with current regulations must carry a M+S or M-S or M&S marking.
In recent years, following the publication of the (EC) 661/2009 regulation concerning type-approval requirements for the general safety of motor vehicles and their components, the 3PMSF marking (3 peaks mountain snow flake, or "Alpine" pictogram) has also been introduced in International Regulations, meaning that for these tires, a series of specific type-approval tests have been arranged on snow and in icy conditions, which, if passed, would guarantee the tire’s final approval.
Period of use and instructions on the registration certificate
The current legislation, as well as the previous Tire Directive, which was part of the vehicle’s type-approval requirements, and current European Regulation, prescribe that the tires indicated in approval by the vehicle manufacturer must have a speed rating that matches the vehicle's top speed. It is further specified in the text that this requirement does not apply to vehicles equipped with “ordinary” tires or, "occasionally" with winter tires for which a lower speed code is allowed (up to Q = 160 km / h). As far as the period of mandatory use of winter gear, the Ministry of Transport established in a 2013 directive that this should run from November 15 to April 15. The same provides for an additional month before - from 15 October – to mount the tires, and one after - until May 15 – to replace the winter equipment.
The use of winter tires on all wheels is strongly recommended to ensure uniform conditions of grip and safety.
Studded snow tires
The use of type-approved winter tires, equipped with studs, is allowed in our country, for vehicles with a total laden mass of up to 3.5 t, under the conditions laid down by a special circular letter from the Ministry of Transport dating back to the '70s: studs, however should not protrude more than 1.5 mm, and the number of studs per tire should be between 80 and 160, maximum speed allowed is 90 km/h on ordinary roads and 120 km/h on motorways, splash guards behind the rear wheels and studded tires must be mounted on all wheels from November 15 to March 15. This provision is still considered to be in force as it does not contrast the current legislation, and pursuant to an article of the Code's regulation on technical provisions enacted and not replaced by new provisions.
These are additional devices intended for use on driving wheels, as specified both by current directives and the UNI11313 technical standard. Vehicle manufacturers are required by vehicle type-approval directives to provide for the use of at least one type of snow-chain for at least one of the types of wheels allowed, or originally approved, for that vehicle. Also 4X4s have the possibility of using snow-chains and the manufacturer must provide for the use of such devices for at least one of the axles, preferably the front one. However, always comply with the instructions of the vehicle manufacturer in the instructions for use and maintenance, to avoid any problems with transmission parts. As regards safety, construction and performance characteristics (in compliance with specific technical standards), other means to be used as an alternative to winter tires are those referred to in the decree of the Ministry of Infrastructures and Transport dated 10 May 2011: Rules concerning additional snow devices for vehicles of category M1, N1, O1 and O2 (cars, light transport vehicles and trailers). According to the decree, these must be approved in accordance with the national standard UNI 11313, or other European equivalent standards, such as the Austrian ON V5117. As far as commercial/industrial vehicles with a mass greater than 3.5t, compliance with these specific rules is not yet required by our law. Therefore, the possibility of using winter devices with characteristics and materials other than traditional metallic ones is not excluded. However, if there is a clear obligation, with specific road signs or regulations, these devices must, in any case, be those "approved" as indicated above.
We shall return on this topic with further details.