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EU Legislation To Prevent Accidents May Compromise Road safety

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ANTRIM, North Ireland, Aug. 21, 2009 -- Ground breaking legislation passed by the European Parliament earlier this year will see all new cars sold in Europe from 2012 fitted as standard with a tyre pressure monitoring system (TPMS). Tyre safety organisations have estimated that up to 80% of cars on UK roads have tyres that are incorrectly inflated. However, fears are being expressed that one of the two TPMS technologies being made available to car companies may in fact put both motorists and the environment at risk.

The two systems, direct and indirect, approach the monitoring of a tyre’s pressure in different ways. The tyre industry favours solutions such as the direct system which places a pressure sensor in each wheel and transmits reliable pressure measurement information back to the car data centre which then informs the driver immediately about the condition of its tyres.

The indirect system, favoured by some car companies and supported by OICA (Organisation International Constructeurs d’Automobiles), is a less expensive option, and measures the rotation rate of the tyres and compares one wheel against the others. Some systems perform an analysis of the vibration characteristics using the ABS sensors. The car’s computer (ECU) analyses the data and works out if the tyre is changing diameter and the software interprets this as a loss of tyre pressure. The delay in providing this information to the driver is considerable opening up the possibility of a rapidly deflating tyre not being detected and the possibility of an accident.

The other crucial difference between the two systems is that the indirect version requires, when the tyre pressures are adjusted or a tyre changed, that the driver must – to make the system effective – re-calibrate the system. This relies heavily on the driver checking the tyre pressures with an accurate gauge, and in the optimum conditions when the rubber is cool, and then hitting the re-set button. With tyre pressures ranking low down on the agenda of most drivers, the process is open to mistakes. This is a fundamental flaw and could provide a false sense of safety to the driver who could be running on severely deflated tyres yet the system is indicating “correctly inflated”

Due to its intrinsic flaws and limitations, independent research proves that the indirect system also compromises two other important environmental benefits that flow from the fitment of TPMS, reducing CO2 emissions and saving fuel. Under inflated tyres are known to have a detrimental impact in both of these areas.

The European Commission is being encouraged to ask the UNECE committee, responsible for implementing the technical details of the new regulation, to favour the accurate tyre pressure monitoring technology which will maximise its contribution to road safety and CO2 reduction, an issue at the top of the EU agenda. A campaign to highlight this road safety issue is being spearheaded by Schrader Electronics, one of the principle developers and suppliers of TPMS, with support from major tyre companies. Leading industry bodies have issued position papers supporting strict performance requirements for TPMS, currently achievable using only the direct TPMS option, these include ETRTO (European Tyre and Rim Technical Organisation), CLEPA (the European Association of Automotive Suppliers) and the European Federation for Transport and Environment.