The city of Harbin, Heilongjiang province has announced a Heavy Air Pollution Contingency Plan, Xinhuanet.com reports, on Dec 12, explaining that it is asking public transportation operators to give free rides to people in the case of a red alert and to develop a staggered rush hour plan for the four-tier alerts — blue (lowest), yellow, orange, and red (highest).

The city also has an emergency management HQ to deal with emergencies on days with heavy pollution that are forecast 72 hours in advance. Under the red alert, Harbin suspends classes for junior middle and primary schools and uses cloud seeding to try to make it rain or snow.

It is also adopting an even-odd-numbered license plate ruling for cars to limit the traffic flow within the 3rd-ring Rd areas to keep 30 percent of the cars off the road. And the authorities will advise people on protection measures through radio, TV, Internet, newspaper and micro blog and text alerts.