The Westmorland Gazette reports that Cumbria police are launching a month-long campaign to get drivers to check that their tyres are safe and legal before winter weather sets in.
Obviously a highly laudable campaign. But one thing is niggling me about the story.
The article talks of the “20p test”, and how you can use a 20p coin to gauge the depth of your tyre tread.
The official minimum specification for tyres on a car is that they should have not less than 1.6mm of tread across the middle three-quarters of the tyre’s width, and all around the edges. Also, there should be no damage or bulging on the sidewalls.
You can measure your tread depth using a suitable depth gauge, available for a few pounds from any Halfords or motorists’ store. Or, at a pinch, you can use a 10p (NOT 20p) coin.
That ring of small dots is approximately 1.6mm away from the edge of the coin, so if you poke the coin into your tyre tread the dots should be hidden. If they aren’t – or if they are anywhere near not being hidden – then you must get your tyres fixed to remain legal. It’s worth bearing in mind that garages probably won’t MoT your car if it has less than 3mm of tread on any tyre, and it’s also my understanding that tyre manufacturers make no warranties below about 3mm anyway.
To be fair to the article (and Cumbria police), they make no mention of the minimum specification – their’s is a safety campaign with its own criteria – but they talk of using the 20p coin to measure your tyre tread depth. Poke the 20p into the grooves and if you can see the edge of that border with the writing on it above the tread then you’re unsafe.
The thing is, that rim with the writing on it is about 2.5mm wide. If you just comply with it, you’re less than 1mm away from being illegal and exceedingly dangerous, and still unlikely to get an MoT certificate without getting new tyres. It’s very dangerous ground the Cumbria police department is treading, as it is actually saying that you ARE safe if you have 2.5mm of tread, when in fact anything less than 3mm is the usual limit of acceptability.
It doesn’t make sense, and it smacks of launching a campaign but being afraid of how it will be received by the many people you’re likely to catch out with it – so dumbing it down to lessen the impact, and getting mired with the conflicting interests so created.