Here the PA news agency answers 13 key questions about the roads.
– What are smart motorways?
They use technology to improve the flow of traffic, including using the hard shoulder as a live running lane and variable speed limits.
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– How many are there?
There are 375 miles of smart motorways, of which 140 miles retain a permanent hard shoulder.
Motorways with sections where the hard shoulder has been removed are on the M1, M5, M6, M23, M25 and M62.
They are designed to increase capacity without the more disruptive and costly process of widening carriageways.
– Why are there safety concerns?
Concerns have been raised about incidents where vehicles stopped in traffic and were hit from behind.
– What is the safety record of smart motorways?
Fourteen people were killed in 2019 on motorways where the hard shoulder was permanently removed or was temporarily used as a live running lane, according to Sunday Times analysis.
Jason Mercer, 44, and Alexandru Murgeanu, 22, died on the M1 in South Yorkshire in June of that year after a lorry ploughed into their stationary vehicles.
– What does the Government say about smart motorways?
An “evidence stocktake” published by Transport Secretary Grant Shapps in March 2020 said that “in most ways” they were as safe or safer than conventional motorways, but the chance of a crash involving a moving vehicle and a stationary vehicle was higher when the hard shoulder was removed.
– What was the result of this report?
An 18-point action plan included installing more places to stop in an emergency and faster rollout of a radar-based system to detect broken-down vehicles.
– What happens if I break down on a smart motorway without a hard shoulder?
Drivers are advised to take the next exit or pull into an emergency refuge area (ERA) if possible.
– How frequent are ERAs?
Emergency areas, motorway service areas or hard shoulders were initially up to 2.5km (1.6 miles) apart, but for new smart motorways being designed they will be no more than 1.6km (one mile) apart.
– What if I cannot reach an ERA or leave my vehicle safely?
If you come to a standstill in a live lane, switch on your hazard warning lights and stay in your vehicle with your seat belt on. Call 999.
– What happens next?
Once Highways England is alerted to a stopped vehicle in a live lane, overhead gantries will display a red X to indicate the lane is closed.
– Are smart motorways used in other European countries?
The vast majority of motorway-style roads in Europe have a permanent emergency lane.
– What do drivers think about them?
An AA poll of 15,000 motorists suggested only one in 10 drivers felt safer on smart motorways without a hard shoulder than traditional motorways.
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