Beijing issued its second smog red alert of the month on Friday, triggering vehicle restrictions and forcing schools to close. A wave of smog is due to settle over the city of 22.5 million from Saturday to Tuesday. Levels of PM2.5, the smallest and deadliest airborne particles, are set to top 500, according to the official Beijing government website. That's more than 20 times the level that is considered safe by the WHO. Half the city's cars will be forced off the road on any given day, while barbecue grills and other outdoor smoke sources will be banned and factory production restricted. Schools will close and residents are advised to avoid outdoor activities. Visibility in some parts of Beijing will fall to less than 1,600 feet on Tuesday when the smog will be at its worst, lingering due to an almost complete lack of wind.
Smog red alerts are triggered when levels of PM2.5 above 300 are forecast to last for more than 72 hours. Although the four-tier smog warning system was launched two years ago, Beijing had not issued a red alert until last week, drawing accusations that it was ignoring serious bouts of smog to avoid the economic costs. Scientific studies attribute 1.4 million premature deaths per year, or almost 4,000 per day, to China's smog. Most of the pollution is blamed on coal-fired power plants, along with vehicle emissions, building construction, and factory work resulting from three decades of headlong economic expansion. The world's biggest carbon emitter, China plans to reduce hazardous emissions from coal-fired power plants by 50% over the next five years, and it says its overall emissions will peak by about 2030 before starting to decline. (Read more China stories.)