Tyre chains for heavy vehicles
If you are driving a vehicle with a maximum authorised mass of more than 3,500 kg, you must carry chains if you expect to be driving on snowy or icy roads.
During the period when a tread depth of at least 5 mm is required, the vehicle must carry chains, regardless of the driving conditions. The chains must be dimensioned to fit the wheels on the vehicle and provide contact between the chain and the road surface at all times. They must be made of metal/steel, be suitable for the weather and road surface conditions and capable of withstanding the stress and strain.
Motor vehicles with a maximum authorised mass of more than 3,500 kg must carry at least three chains:
- One dimensioned to fit the front wheels
- Two dimensioned to fit the drive wheels
However, this does not apply to motorhomes with a maximum authorised mass between 3,500 kg and 7,500 kg.
A vehicle combination (a motor vehicle/tractor unit and a trailer, each with a maximum authorised mass above 3,500 kg) needs to carry at least seven chains if the motor vehicle has twin wheels on the drive axle:
- One dimensioned to fit the front wheels of the tractor vehicle
- Four dimensioned to fit the drive wheels of the motor vehicle
- Two dimensioned to fit the wheels of the trailer
If the motor vehicle (tractor unit) in a vehicle combination has single wheels on the driving axle or uses double chains, the requirement is five chains. Double chains are chains that cover both wheels in a twin-wheel arrangement.
- One dimensioned to fit the front wheels of the tractor vehicle
- Two dimensioned to fit the drive wheels of the motor vehicle
- Two dimensioned to fit the wheels of the trailer
For motor vehicles equipped with an automatically operated chain deployment system (automatic chains) for the drive wheels, this will replace two chains if the vehicle has twin wheels mounted on the driving axle.