Tyres Are Becoming an Emissions Issue. Measuring Them Is the Hard Part.
For decades, vehicle emissions were largely understood through the exhaust pipe. Regulation, engineering priorities and public attention focused overwhelmingly on tailpipe pollutants, shaping the direction of vehicle development across the industry. But the picture is changing.
As exhaust emissions continue to reduce, attention is increasingly shifting towards non-exhaust sources of pollution, particularly tyre wear. What was once considered difficult to quantify is now being measured with growing confidence, bringing tyres firmly into the wider emissions conversation. This change matters.
Once something can be measured consistently, it can be compared. Once it can be compared, it can be regulated. So, tyres now sit directly at the centre of this transition.
The complexity behind tyre wear measurement
At first glance, tyre wear might appear relatively straightforward to assess. In reality, it is one of the most technically complex areas within vehicle emissions measurement.
Unlike exhaust emissions, tyre wear does not originate from a single controlled system. It emerges from the interaction between multiple variables operating simultaneously and continuously changing in real-world conditions.
Vehicle mass, torque delivery, tyre compound, road surface texture, ambient temperature, inflation pressure, driving style, regenerative braking behaviour, speed profile and cornering dynamics all influence wear behaviour in different ways.
Even relatively small changes in operating conditions can alter the rate, composition and distribution of emitted particles. This creates a significant measurement challenge.
Measuring tyre wear in tightly controlled laboratory conditions can provide valuable insight, but it can also reduce the complexity of the environment being studied. Real-world operation introduces transient events, unpredictable surface interactions and behavioural variability that are difficult to fully replicate in simulation alone.
The result is that tyre wear is not a single fixed value. It is a dynamic outcome shaped by context.
Why methodology matters
As regulatory attention grows, the industry is facing an increasingly important question: How should tyre wear actually be measured?
Different methodologies often reveal different parts of the picture. Some approaches focus on gravimetric mass loss. Others examine airborne particulate matter. Some systems analyse particle number and size distribution in real time, while others focus on deposited material or laboratory abrasion rates. Each methodology has strengths and limitations depending on the question being asked.
This is one of the reasons why standardisation and repeatability have become such important industry priorities. Without robust and transparent methodologies, comparisons between tyres, vehicles or operating conditions become difficult to interpret with confidence.
The challenge is generating data that is meaningful, comparable and representative of real-world behaviour. Manufacturers, suppliers and regulators are attempting to establish a clearer understanding of non-exhaust emissions performance.
Regulation is accelerating this change
The regulatory landscape is now moving quickly.
Euro 7 is expected to introduce tyre abrasion limits for the first time, formally bringing tyre wear into vehicle emissions compliance frameworks. At the same time, research into particulate matter, microplastics and urban air quality continues to expand the focus on non-exhaust emissions globally.
This changes the role tyres play within vehicle development.
Tyres are no longer solely evaluated through the lenses of durability, rolling resistance, grip or efficiency. Increasingly, they are also being assessed as contributors to a vehicle’s environmental impact. That creates a far more complex engineering challenge.
Reducing wear cannot happen in isolation. Improvements in one area may introduce trade-offs elsewhere, whether in braking performance, wet grip, longevity, efficiency or overall vehicle dynamics. The objective is no longer optimisation of a single parameter - it is optimisation within a highly interconnected system.
Why real-world testing matters
This is where real-world testing becomes increasingly valuable.
Controlled environments remain essential for repeatability and development work, but real-world testing provides an additional layer of understanding that laboratory conditions alone cannot always capture.
Transient acceleration events, road surface variation, weather conditions, vehicle loading and route characteristics all influence wear behaviour in ways that can materially affect outcomes.
Understanding how tyres behave across different vehicles, applications and operating environments is becoming critical for both engineering development and regulatory preparedness.
It is also becoming increasingly important for manufacturers seeking independent benchmarking data that reflects how products perform outside idealised conditions.
Measuring tyre wear outside the lab
At Emissions Analytics, this challenge has driven the development of our BTAS (Brake and Tyre Assessment System) testing capability.
BTAS has been designed to measure tyre wear and non-exhaust emissions in real driving conditions, helping translate a highly dynamic system into measurable, comparable and actionable data.
Our testing supports:
Comparative tyre benchmarking
Real-world wear assessment
Vehicle-to-vehicle comparison
Operating condition analysis
Independent emissions evaluation
Development and R&D programmes
Regulatory preparedness work
By combining vehicle testing expertise with advanced emissions measurement methodologies, BTAS allows tyre behaviour to be assessed within the environments where vehicles actually operate. That matters because tyre wear is no longer a niche research topic, it’s becoming a central part of how vehicle emissions are understood.
The industry is entering a new phase
The conversation around tyre emissions is evolving rapidly. The industry is moving from asking whether tyre wear matters to asking how it should be measured, compared and ultimately reduced.
The organisations that develop robust measurement capability earliest will be best positioned to navigate the next phase of non-exhaust emissions regulation, engineering development and environmental scrutiny.
The challenge ahead is not simply generating cleaner vehicles, it’s understanding every source of emissions those vehicles produce.
