Roland Perry wrote:
In message , at 14:38:46 on Mon, 9 Dec 2019,
Recliner remarked:
Vehicle pollution will be sucked out of the road under plans to install
cat’s eye-style filters at the most toxic junctions.

Technology has been developed that uses low-energy fans between lanes to
pull in exhaust fumes before treating the pollution at the roadside.
Initial tests suggest that it can remove an average of 30 per cent of
dangerous pollutants, including fine particles from brakes and tyres

...

When cars stop, they trigger a roadside sensor and fans pull in particulate
matter,

I doubt that stationary cars create much in the way of particulate from
their tyres and brakes.

The process of slowing down certainly will have done, so there will be
local clouds of particulates to suck in.

On the bit of road they slowed down, not the section they are
stationary.

From the picture, there's a row of air inlets between the lanes. They're
not relying on precisely lining up with the stationary vehicle.