No new smart motorways without a hard shoulder will open in England unless radar technology to detect broken-down vehicles is installed, Highways England has announced.

The Government-owned company also said retrofitting the Stopped Vehicle Detection (SVD) system to the existing network will be accelerated by six months.

An action plan launched by Transport Secretary Grant Shapps in March 2020 included a deadline of rolling out SVD across the entire network by March 2023, but this will now be completed by September next year.

We are determined to do all we can to help drivers feel safer

There is growing concern over all lane running (ALR) smart motorways – which involve the hard shoulder being converted into a running lane – due to several fatal accidents involving stationary vehicles being hit from behind.

In a progress report, Highways England described smart motorways as “the safest roads in the country”, stating the number of fatalities per distance driven is a third higher on conventional motorways than ALR motorways.

It said 15 people were killed on motorways without a permanent hard shoulder in 2019, up from 11 in 2018.

Mr Shapps said: “Despite the data showing that fatalities are less likely on All Lane Running motorways than on conventional ones, this doesn’t mean all drivers necessarily feel safe on them.

“That is why I tasked Highways England last year with delivering an action plan to raise the bar on safety measures even higher. This progress report shows the extensive work already carried out, but we want to do more.”

Highways England’s acting chief executive Nick Harris said: “We’ve made good progress delivering the improvements set out in the 2020 stocktake, but we are not complacent and are examining ways to improve safety further.”

Claire Mercer, whose husband Jason Mercer died on a smart motorway in June 2019, told the PA news agency: “It’s all compromises. Nothing is new.”

She went on: “Nothing short of giving back the hard shoulder in every single instance will be acceptable.”

Sheffield coroner David Urpeth told an inquest in January that “a lack of hard shoulder contributed” to Mr Mercer’s death, and that smart motorways “present an ongoing risk of future deaths”.

The numbers mean nothing if it's your car that breaks down and you can’t reach an emergency refuge

Steve Gooding, director of motoring research charity the RAC Foundation, said: “A gap remains between what the data suggests about the safety of smart motorways and what many drivers believe to be the case.

“The numbers mean nothing if it’s your car that breaks down and you can’t reach an emergency refuge.

“The challenge for Highways England is not just doing the upgrade work but communicating to road users that all lane running requires a different mindset from drivers – only then will they start to turn public opinion around.”

Last month, Mr Shapps commissioned the Office of Rail and Road to carry out an independent review of safety data for the controversial roads.

He also ordered his officials to continue their work with Highways England – the Government-owned company responsible for England’s motorways and major A roads – on “developing possible future options” for reducing accidents on smart motorways.

The Commons’ Transport Select Committee is conducting an inquiry into smart motorways, with chairman and Tory MP Huw Merriman warning there are “genuine worries” about the roads.