Tightening tyre laws

John Dorken, chief executive, Tyre Industry Federation, looks at proposals for new EU tyre regulation

To the average vehicle owner the tyre, compared with many other components, tends to be of little interest. Yet it is a key part of the vehicle, providing as it does the only point of contact between the vehicle and the road. Thus it is integral to the safety of the vehicle, its steering and handling, the comfort of the ride it gives, the energy it uses and the noise it makes.
The tyre has long been the subject of specific regulation, the feeling being that the make-up, and the operating characteristics, of the tyre are too important to society at large to be left to market forces. So over the years, and at an increasingly international level, there has been a series of measures to regulate the characteristics of tyres. The most recent substantial measure was a Directive of the European Communities in 2001 (EC 2001/43), the primary purpose of which was to set down limits to the noise that a tyre could make in contact with the road.

Limiting noise
That was, however, not the end of the story. Inside the directive a little time bomb was inserted, which has been steadily ticking away ever since. First the directive listed a more stringent set of noise limits that should in due course be introduced. The European Commission was required under the directive to produce a report on whether, and to what extent, technical progress would, without safety being compromised, permit the introduction of these limits. Perhaps more seriously the Commission was also required on the basis of that report to propose amendments to the directive with a view to ‘introducing provisions relating to safety, environmental and rolling resistance aspects’.
So, considerably later than it should have done and after an initial bout of consultation, the Commission put forward toward the end of May proposals for a new comprehensive regulation that would, amongst other things, substantially tighten up the rules governing tyres. In brief the regulation would:

  • tighten the existing noise limits;
  • introduce, for the first time, standards for the rolling resistance of tyres; 
  • provide  for the testing of passenger car tyres in the wet;
  • making mandatory the fitting of tyre pressure monitoring systems (TPMS).  

The proposal envisages an implementation schedule starting in 2012 and completed in 2020. The tyre industry has considerable misgivings about these proposals. The proposal for the mandatory fitting of TPMS, provided that the actual systems prescribed are acceptable, seems eminently sensible. The idea of having an integrated regulatory framework is also to be welcomed, and it should be possible to improve safety, reduce CO2 emissions and further reduce noise.
This is, however, only possible if all tyre performance criteria are considered together and the requirements on any particular measure are not taken too far. As it is, while the industry supports the intention to lower the current noise limits, the thresholds currently proposed will seriously jeopardise vehicle and consumer safety without any significant improvement in environmental noise. The fact is that three to four times greater reduction in noise can be achieved by reducing speed in congested areas or by improvements in road surfaces. To try to do it through just the tyre will compromise safety, which is simply not acceptable.

Truck tyres
Take for example truck tyres. The biggest problem here is with traction (drive axle) tyres. Here a reduction of 3dB(A) compared with the current limits, as has been proposed, would be difficult to achieve without degrading the adherence properties of these tyres. In effect these tyres must have aggressive tread patterns to allow them to move heavy goods vehicles forward in slippery condition.
If the traction properties are degraded more trucks will have difficulties when even a small amount of snow falls, effectively blocking roads for all vehicles. Recent studies by an authoritative German research institute have shown a significant correlation between truck tyre noise and snow adhesion. The quieter tyres are worse in snow traction. In addition, of the five traction tyres tested only one would pass the proposed EC limits, but with no margin for error.
Turning to rolling resistance, the industry supports the objective of reducing CO2 emissions through introducing limits and action to ensure that correct tyre pressures are maintained. However, it is not able to go as far as the limits put forward under the second stage of the two-stage process the Commission proposes.

Implementation period
We should also not forget the need to ensure that there is a reasonable length of time to implement any of the proposals. The timetable put forward by the Commission looks impossibly tight. There are a number of stages that have to be gone through before a new, conforming tyre reaches the market. The tyre has to be designed and engineered to meet the new combinations of requirements, and this is not a simple process given all the requirements that it has to meet.
Once the design is completed the prototype has to be tested and type approved. That alone may be a lengthy process, not only because of the number of tests that have to be undertaken but also because some of the tests, for example that for wet grip, can only be undertaken under strictly controlled climatic conditions, which may prevail at only certain times of year.
We have to remember too that there would be a large number of new types and sizes of tyres to be tested in a very short timeframe, so there would be a huge demand on a limited number of test facilities. Inevitably the testing of many tyres would be delayed.  In the light of these concerns the industry has put forward some proposals for revised implementation dates.
The industry supports the principle of tighter regulation in all these areas. However, the legislators’ ambitions must be tempered by reality. In some cases it will simply be impossible to meet the combinations of limits being proposed. In any event the timetable for implementation is unachievable. Let’s hope that over the coming months the proposals will be modified to meet the industry’s concerns. If not, the tyre market could well face costly disruption.

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