Cities have turned their attention to bus safety in the wake of the tragedy in Chengdu, where flames engulfed a bus on Friday, killing 27 passengers and injuring 72.
Beijing Public Transport Company started checking all buses for safety problems including leaks, the effectiveness of emergency power switches and fire extinguishers.
The company confirmed all buses in Beijing are equipped with emergency doors and windows.
Shenyang in Liaoning province also reacted quickly to the accident.
The Shengyang municipal transportation bureau decided on Saturday that buses will be running without air conditioners this summer, and within a month all sealed windows will be replaced by pull-and-push windows.
All buses in the city are required to be equipped with enough fire extinguishers.
In addition, the bureau is requiring bus companies to reinforce supervision of passengers on entry and exit.
Guangzhou in Guangdong province is proposing a law to ban passengers taking anything with an unusual smell on buses in the city.
New air-purifying equipment will also be installed to improve air quality in buses, according to the Guangzhou Municipal Transportation Committee.