Tyre wear pollution can be 1,000 times worse than exhaust emissions
Pollution from tyre wear can be 1,000 times worse than what comes out of a car’s exhaust, Emissions Analytics has found
Vehicle tyre wear pollution is completely unregulated, unlike exhaust emissions which have been reduced by car makers thanks to the pressure placed on them by European emissions standards.
Non-exhaust emissions (NEE) are particles released into the air from brake wear, tyre wear, road surface wear and resuspension of road dust during on-road vehicle usage. No legislation is in place to limit or reduce NEE, but they cause a great deal of concern for air quality.
The problem is being exacerbated by the increasing popularity of large, heavy vehicles such as SUVs, and growing demand for electric vehicles, which are heavier than standard cars because of their batterie
NEEs are currently believed to constitute the majority of primary particulate matter from road transport, 60 percent of PM2.5 and 73 percent of PM10 – and in its 2019 report ‘Non-Exhaust Emissions from Road Traffic’ by the UK Government’s Air Quality Expert Group (AQEG), it recommended that NEE are immediately recognised as a source of ambient concentrations of airborne particulate matter, even for vehicles with zero exhaust emissions of particles – such as EVs.
To understand the scale of the problem, Emissions Analytics – the leading independent global testing and data specialist for the scientific measurement of real-world emissions – performed some initial tyre wear testing. Using a popular family hatchback running on brand new, correctly inflated tyres, we found that the car emitted 5.8 grams per kilometer of particles.
Compared with regulated exhaust emission limits of 4.5 milligrams per kilometer, the completely unregulated tyre wear emission is higher by a factor of over 1,000. Emissions Analytics notes that this could be even higher if the vehicle had tyres which were underinflated, or the road surfaces used for the test were rougher, or the tyres used were from a budget range – all very recognisable scenarios in ‘real world’ motoring.