Hauliers have complained that a cycle route for students going to and from Swansea University's new Bay Campus is poorly designed and “an accident waiting to happen”.
32-tonne lorries travel from Fabian Way along Baldwin's Crescent and would be unable to stop in time should a cyclist cross into their lane, say local businesses.
Steve Norman, managing director of Stenor Environmental Services, told the South Wales Evening Post that there had already been two near misses with cyclists wearing headphones in just one week.
"We had an incident last Friday and an incident on Monday this week," he said. "The incident on Friday was a real close one.
"It is the main access to the port and it is becoming the main access to the university for people who aren't driving — it's an accident waiting to happen."
Swansea University student Ed Kingham who cycles to his lectures along that route, said:
"Something needs to change before someone gets hurt."
Robert Steins, of Steins Haulage, said: ”We are having to make sure that our drivers don't make any manoeuvres that will endanger anyone else's life. We’re having to police it."
And William Briggs, of Briggs Coaches, said: "This is a busy little road and it doesn't seem that much thought has been given when planning it."
A Swansea University spokeswoman said it had liaised with the council, which confirmed it is reviewing the situation.