An information reading device, similar to an airplane's black box, will be installed in all elevators in public places in Beijing, providing real time monitoring by 2015.

"With the network, maintenance staff will receive a text message about details such as the location as soon as possible if an elevator breaks down," said Zhao Changshan, head of the Beijing Bureau of Quality and Technical Supervision on Wednesday, the Beijing Times reported.

"They will rush to the scene to rescue trapped passengers within 30 minutes," he said.

There are 140,000 elevators in Beijing, more than in New York and many other major cities in the world and the city adds on average 10,000 more elevators every year.

But 24 percent of the elevators have been in service for more than 10 years, posing potential safety risk.

?"More than 2,000 elevators in commercial places, bus stations and residential buildings will have such monitoring devices installed this year," Zhao said, "and it will expand to cover all elevators in public places in the next three years."