Buses and minibuses will have to cover their routes within a specified time and any deliberate delay or haste would invite penalties for the operators, the state government has decided.

The move is among the measures being drawn up to reduce rash driving to pick up more passengers, transport department officials said.

The time to complete a round trip for all the routes in the city and its adjoining areas will be decided in consultation with bus owners and police, the officials said.

Officers managing traffic will detect whether a bus is adhering to its timeline and record violations.

"Specifying a timeline will ensure that buses follow a pre-determined interval leaving the terminal points. This interval can be 10, 15 or 30 minutes depending on the route length," state transport minister Snehasis Chakraborty told Metro.

"A fixed timeline would also mean that buses won't delay unnecessarily. This will reduce the chances of road rage. Repeated offenders will be penalised."

The move to arrive at a timeline for all routes follows a nudge from chief minister Mamata Banerjee, who had expressed shock over the death of a school student in an accident in Salt Lake involving two racing buses on Tuesday.

"Both buses were of route 215A. The drivers were racing to complete the trip ahead of the other. The first to reach would be the first to leave for the next trip," said Pradip Narayan Bose, the secretary of the West Bengal Bus and Minibus Owners Association.

Both buses are owned by the same person.

Close to 2,000 private buses operate on 30-odd routes covering Calcutta and the districts of North and South 24-Parganas and Howrah.

Leaders of bus unions said all routes have a timeline even now and there's a "time-keeper" who keeps a record of the time taken by a bus to complete a round trip.

"Those failing to adhere to the time are usually given a verbal warning. There are no well-defined penalties and the offenders get away easily," Bose said.

Transport department officials admitted there is no mechanism to check how many private buses are violating their assigned timelines regularly.

Officers said buses often move at a snail's pace, or stop frequently and for long periods, to pick up as many passengers as they can, only to accelerate at the sight of another bus on the same route.