Beijing just issued its first ever red alert for smog levels

Beijing is bracing itself for three consecutive days of severe smog this week, prompting China's capital city to issue its first-ever red alert Monday. The alert, which urges the highest level of caution in the city's four-tier warning system, will begin Tuesday at 7 a.m. and end at noon on Thursday.

Schools will be advised to close, factories and construction sites will be temporarily shut down, and severe limitations on traffic will be enforced. Cars with odd and even license plate numbers will be required to alternate days driving. "It is history — this is a precedent set," Ma Jun, director of the Institute of Public and Environmental Affairs in Beijing, said. "This is extremely important to stop children from being exposed to such a high level of pollution."

Last week, Beijing issued the year's first orange alert — one rung below the red alert — as smog in some areas rose to levels 40 times what is considered safe by the World Health Organization. Though levels are now lower than they were last week, the heightened alert was made in anticipation of what's to come, the BBC reports.

As of Monday at 6 p.m. local time, air pollution levels were 10 times what is considered safe.