WPQ answer – Air quality speed limits

The Department for Transport has provided the following answer to your written parliamentary question (15521):

Question:
To ask the Secretary of State for Transport, what criteria are used to determine when temporary air quality speed limits are used on the M4 near Heathrow. (15521)

Tabled on: 26 February 2024

Answer:
Guy Opperman:

National Highways implemented a speed restriction of 60mph on the M4 westbound at junctions 3 to 4 in December 2022 to achieve nitrogen dioxide (NO₂) compliance in the shortest possible time.

The answer was submitted on 04 Mar 2024 at 14:32.