China's traffic authority said on Thursday more vehicles than usual are expected to be on the highways over the extended break because of the country's toll-free holiday policy.

The authority said road safety remains the top concern during the upcoming annual travel boom.

A total of 660 million passengers will travel by road and water during the longer-than-usual eight-day Golden Week holiday, which combines the National Day holidays and Mid-Autumn Festival and starts on Sept 30.

An average of 80.9 million passengers are estimated to use the roads every day during the period, up 8.9 percent compared with last year, said ministry spokesman He Jianzhong at a press conference in Beijing.

"This year, the holiday traffic will see an increase in private vehicles for self-driving trips, spurred by the lifting of tolls on highways," He said.

Free pass

The policy will allow small passenger cars and motorcycles to pass freely on tolled roads and bridges nationwide. It will come into effect on Sept 30 and run until the end of the legal holiday period, according to the ministry.

The traffic is expected to be heaviest on the first and the last day of the holiday, when an estimated 86 million passengers could use the roads, He said.

"We suggest people avoid peak hours and travel when there is less traffic, based on real-time traffic condition information provided by authorities," He said.

Although small passenger cars do not have to pay highway tolls, they still have to slow at tollgates to get a pass card, which may lead to serious road congestion.

"To ease traffic, we have asked road companies to set up special lanes for cars eligible for a free pass, and we have erected signs to separate such cars from trucks or buses before the vehicles pull into the tollgates," He said.

He added that tollgate entry lanes may be changed into exit lanes if there is more traffic from the other direction.

In East China's Jiangsu province, 400,000 highway pass cards will be added to tollgates to cope with the possible traffic surge, according to the provincial expressway network operation and management center.

The center told China Daily that drivers should take a card when entering the highway and later return it at the exit point. The bars at the tollgates will be removed to speed up traffic.

According to Shanghai-Nanjing Expressway Co Ltd, which manages the province's busiest highways, a driver could go through such tollgates in two or three seconds instead of about 16 seconds, which is the time it took in the past.

Safety concerns

To move the record number of passengers, 840,000 long-distance coaches will be used during the holidays, making 2.6 million trips every day, the ministry said.

The intensive transport has raised public concerns about road safety for long-distance buses, especially sleeper buses.

Last month, a fatal traffic accident occurred in Northwest China's Shaanxi province, killing 36 passengers on an overnight sleeper bus. The accident flagged safety issues on the so-called red-eye buses as they usually travel overnight.

He Jianzhong said such buses, which travel more than 800 kilometers, still have a strong market demand during peak travel times.

He said the ministry will take stricter measures to prevent any threats to travel safety, such as urging the buses to stop running between 2 am and 5 am and requiring drivers to take compulsory shifts at night to prevent fatigued driving.

In addition to safety inspections on long-distance sleeper buses and chartered tourism buses, He said the ministry also inspects the condition of highways and bridges before the holidays.

"The local traffic authorities will make efforts to ban overloaded vehicles from driving on highways, which may endanger roads and bridges," he said.

Cang Wei in Nanjing and Shi Yingying in Shanghai contributed to this story.

Contact the writer at tanzongyang@chinadaily.com.cn