Concerns over new M1 'smart' motorway designs
Concern has been voiced over the design and impact of a new stretch of "smart" motorway on the M1.
The £120m project will see a 7.5-mile (12km) stretch from Junction 23a to 25 fitted with electronic signs to encourage use of all four lanes.
The RAC has questioned the number of safety bays available and haulage firms want assurances work will not overrun.
Highways England said the designs had proved successful elsewhere and any short-term delays will be justified.
The work, which runs through Leicestershire and Derbyshire, is due to last 18 months.
Smart motorways use cameras and overhead signage to control the speed and flow of traffic, increasing the capacity of motorways without the cost of physically widening them.
Simon Williams, from the RAC, said the organisation is concerned the design shows all four lanes being used all of the time.
He said: "Our main concern is the spacing of the emergency refuge areas, which has got wider.
"On the M42 the refuges are about 500-800m apart - but as [smart motorway] schemes have rolled out the refuges have got up to 2.5km apart."
Local businesses said they wanted no repeat of a 12-month overrun in a similar scheme on another section of the M1.
Wayne Evans, from a haulage firm in Ambergate, said: "Without a shadow of a doubt the planned delays will cost us tens of thousands.
"It is a massive corridor for us and the problem will be if the short-term pain becomes a longer term issue, like it did further north."
Highways England project manager David Cooke said: "The prerequisite is that we have absolutely 100% CCTV coverage of all the sections in all light conditions.
"If there is an incident we need to be able to protect the travelling public with red Xs to close lanes and reduce the speed limit."