945: Peak concentration of PM2.5 reached in Beijing on Nov 30. [Photo/China Daily]

2. Law on Air Pollution Prevention and Control

As serious smog has occurred frequently across many parts of the country in recent years, lawmakers are working to find ways to prevent it.

A law was passed in August, aiming to improve the nation's environment.

It contains comprehensive measures targeting various sources of contaminants. Emissions from motor vehicles and marine vessels face tougher legal restrictions. Ships are asked to use standard diesel fuel in an effort to cut emissions. To cope with a growing number of vehicles, local governments are required to impose driving restrictions.