Letter: The Report Is Correct – A Clean Air Zone is Not the Answer

Published on: 18 Jun, 2026
Updated on: 18 Jun, 2026

From Jim Allen

In response to: A Clean Air Zone Would Not Be Appropriate For Guildford, Says Report

Five years ago I took part in an air pollution study with Professor Prashant Kumar of the University of Surrey, Professor and Chair in Air Quality and Health, also the founding director, Global Centre for Clean Air Research (GCARE) and co-director, of the Institute for Sustainability.

We utilised multiple monitoring sites taking measurements throughout Guildford. Our findings indicated that when traffic on the A3 experienced significant congestion, a corresponding increase in pollution levels was observed across various locations in Guildford.

Conversely, as traffic flow improved, pollution levels dissipated within a similar time-frame. This suggests that a clean air zone would likely have minimal impact unless the A3, specifically from Send to Compton, were to become entirely traffic-free.

No such zone would be effective under current conditions. In reality, the air in the A3 Clay Lane area is largely free of particulate matter. Furthermore, a greater proportion of pollution now originates from tire wear due to heavier vehicles, a trend that has emerged since the introduction of electric vehicles, lead-free fuel and modern diesel engines.

Localised pollution hotspots are often found adjacent to high-rise buildings, where airflow is restricted, and in areas where traffic is slowed by infrastructure such as bus lanes. Optimising traffic flow demonstrably reduces pollution.

Should anyone wish to measure pollution levels, they are welcome to borrow my air pollution and decibel meters.