Checking the tread depth
- The tread depth should be measured in the principle grooves. These are the ones which contain “tread wear indicators”, which are raised sections in the base of the groove. They are usually 1.6mm to 2mm above the base of the groove.
- Measure each groove depth across the tread width and in several places around the tyre circumference.
Braking distances on wet roads increase as the tread pattern depth reduces. To maintain an adequate safety margin we support the advice given by road safety organisations, including Roadsafe and RoSPA and leading European car manufacturers who recommend replacing tyres when the tread depth reaches 3.0mm.
Checking tyre pressures
- The recommended tyre pressures for your vehicle will be found in the vehicle handbook or on a placard mounted on the vehicle e.g. behind the petrol filler cap or on the drivers door pillar.
- Always check pressures when the tyres are cold, never adjust tyre pressures during or immediately following a journey.
- Check tyre pressures every two weeks and adjust when necessary. Always refit the valve cap.
- Low tyre pressures reduce the tyre’s performance and increase fuel consumption. It is advisable to obtain a reliable pressure gauge which can be purchased at most motorist centres at a reasonable cost.
- Tyres may be inflated with nitrogen, this results in better handling and road holding. It can also reduce tread wear and increase tyre life by up to 25%. It can also improve pressure retention and increase mpg by 2%.
- It is important to visually check the condition of tyres on a regular basis.
- Lumps and bulges may indicate the tyre has been damaged internally. If there is any doubt as to the tyres condition then the tyre should be immediately removed from service until it has been checked by a suitably qualified tyre expert.
- Any cut to the tyre, which is deep enough to reach the internal structure renders the tyre unsafe. It should be replaced or where appropriate repaired.
- Tyres deteriorate with age and if cracking or crazing is present it may indicate that the rubber is perished and the structural integrity cannot be assured. The tyre should be immediately removed from service until it has been checked by a suitably qualified tyre expert and if there is any doubt replaced.
Tyres and the law
The law requires vehicle drivers and owners to maintain tyres in a good and safe condition.
The main points within Construction and Use Regulation 27 are:
- The tyre must be suitable for the purpose the vehicle is being used.
- The tyre must be suitably inflated for the purpose the vehicle is being used.
- The tyre must not have a cut, in excess of 25mm or 10% of the tyre section width whichever is the greater, which is deep enough to reach the tyre’s internal structure.
- The tyre must not have a lump, bulge or tear caused by separation or partial failure of its structure.
- The tyre must not have any ply or cord exposed.
- The tyre tread depth must be a minimum of 1.6mm measured in a band comprising the central 75% of the tread width and continuous around the tyre circumference.
- The tyre must be maintained in a condition so that it is fit for the purpose the vehicle or trailer is being used and must not have any defect which may cause danger to the road surface or damage to persons in or on the vehicle, or other road users.
FOR EACH AND EVERY TYRE OFFENCE THERE IS A MAXIMUM FINE OF £2,500, WITH DISCRETIONARY DISQUALIFICATION AND A COMPULSORY DRIVING LICENCE ENDORSEMENT OF 3 PENALTY POINTS