Radar systems to detect breakdowns and smashes will be added to the Milton Keynes-Northampton stretch of the M1 before it opens as a smart motorway.
But extra safety measures on an existing four-lane carriageway between Daventry and the M6 will not be up and running until September 2022.
Highways England confirmed they are accelerating installing Stranded Vehicle Detection technology on all the country’s smart motorways following a Department of Transport “stocktake”.
SVD was due to be retro-fitted on a £373million upgrade project between junction 13 and junction 16, due for completion late next year. But the high-tech safety system will now be added before the 23 miles of ‘all lane running’ motorway opens.
SVD alerts controllers to vehicles stuck on the motorway allowing them to take action to shut off lanes using red X signs on gantries and flash emergency messages and speed limits.
It will also be installed on another 14-mile stretch of the M1 between junction 16 and 19 which opened as a four-lane smart motorway in 2018 — but not until later next year.
But transport secretary Grant 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.
“Alongside the raft of measures already undertaken, today I am announcing that all new All Lane Running motorways will open with stopped vehicle detection technology in place, as well as a programme to speed up the roll-out of the technology on previously built stretches of All Lane Running motorways to next year. This will help us further reduce the risk of accidents on the country’s roads.
“So-called smart motorways started to be built in 2001 and I am determined to ensure that technology and exacting standards are in place.
Critics labelled doing away with hard shoulders in favour of a fourth live lane potentially lethal after a number of fatal accidents on similar stretches.
Speed sensors are supposed to pick up incidents and safety refuges are built at regular distances allowing drivers to get off the carriageway if they break down.
But these refuges can be more than a mile apart and coroners have highlighted a number of deadly crashes where cars have been stranded and ploughed into by other traffic.
Work on part of the upgrade between junction 13 and junction 16 is already finished near Milton Keynes but one lane will remain coned off with a 60mph temporary speed limit until SVD is installed.
Highways England’s Acting Chief Executive Nick Harris said: “I want Highways England to continue to be an organisation that listens, and puts the safety of road users first.
“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.
“We will continue implementing the findings, and will work with drivers to make increasingly busy motorways safer for everyone who uses them.”