Creating extra lanes on a busy stretch of the M1 will take up to two years to complete.
But the Highways Agency has told the Express it is confident construction work will not turn the six-mile stretch, between junctions 39 and 42, into a crash hotspot.
Project manager Lynne Biddles said the agency would learn from the impact of a similar scheme on the M62 between Morley and Halifax, which is dogged by accidents every week.
She said: “The M62 is busy at all times but there won’t be the same level of traffic on the M1.
“Safety is always a high priority for us. We’ll look at what lessons we can learn from the M62 and apply them here.”
Hard shoulders will be converted into extra lanes in both directions. It means motorists who break down will have to limp to the nearest “refuge” bay.
Ms Biddles said: “Research shows that most people who break down can limp along, but if they can’t then our advice would be to pull onto a verge.”
New sensors under the surface of the road will detect when a crash has occurred and notify drivers on overhead signs.
Ms Biddles said the system, which includes new CCTV cameras, could improve how quickly emergency services respond to crashes.
And she said variable speed limits would help to reduce congestion and make the stretch more reliable for people.
She said: “We hope traffic will flow more smoothly, without stops and starts.
“If you know you’ll get along at a steady 40 or 50mph, you can plan journeys better.”
The agency is hoping to start work later this year.