The friction between tire and road is essential to ensure drivers’ safety. However, the friction also leads to abrasion of both the tire and the road. The particles generated, known as Tire and Road Wear Particles (TRWP), are a mixture of tire tread fragments and road surface elements. These particles are commonly considered microplastics because of their size and composition.
TRWP generation and levels in the environment do not depend on tire design only. Several external factors, such as driving behavior, road and vehicle characteristics, and weather, can together have a bigger influence on the rate at which TRWP are formed. Therefore, to consider all these factors, solutions for TRWP require a holistic, science-based, and stakeholder-driven approach.
An emission standard called Euro 7 is under development with the purpose of reducing air pollution from new motor vehicles sold in the EU to meet the European Green Deal’s zero-pollution ambition. Euro 7 is expected to be implemented from 2025. The Euro 7 emission standards will be the first worldwide ones to move beyond regulating exhaust pipe emissions. The standards will set additional limits for particulate emissions from brakes and rules on wear particle emissions from tires. Euro 7 is expected to utilize the development work done in UNECE (United Nations Economic Commission for Europe), which aims to develop a test method to determine tire abrasion.
Nokian Tyres is a full member of the European Tyre and Rim Technical Organisation (ETRTO) and participates in global standardization work. ETRTO is deeply involved in UNECE’s tire abrasion test method development work. The target of the method is to have a feasible tire abrasion rate test method with the following characteristics: repeatable, reproducible, cost efficient and practicable, representative of real driving environment, usable for regulation purpose and open to all worldwide.
Parallel to the regulatory work, Nokian Tyres is developing further in-house testing capabilities to fulfill the future demands of creating durable tires. To help build the scientific knowledge as well as develop practical solutions for reducing the levels of these particles found in the environment, the European Tyre and Rubber Manufacturers’ Association (ETRMA) launched the multi- sectorial TRWP Platform in July 2018. As a member of ETRMA, Nokian Tyres contributes to this work as well.
Want to read more of tire and road wear? Here is a link to ETRMA's page on the subject.