Beijing Issues Second Smog 'Red Alert' Of Month

Beijing has issued its second smog "red alert" of the month.

A wave of smog is expected to settle over the city of 22.5 million people between Saturday and Tuesday.

The Chinese government predicts Levels of PM2.5 - the smallest and deadliest airborne particles - are predicted to top 500 - more than 20 times the level the World Health Organisation predicts as safe.

While the alert is in place, half the city's cars will be ordered to stay off the road, schools will be closed and factory production limited.

Beijing's residents are being advised to avoid outdoor activities and barbecues will be banned.

Visibility is predicted to fall to less than 500 metres (1,600ft) on Tuesday when the smog is at its worst as an almost complete lack of wind leaves smog lingering over the city.

Smog red alerts are triggered when levels of PM2.5 above 300 are predicted to last for more than 72 hours.

The four-tier smog warning system was put in place two years ago but this is the only the second time one has been issued. T he first was last week .

The delays in the alerts have brought criticism of the government with people suggesting it has been ignoring serious bouts of smog because of the cost to the economy.

Most of the pollution is blamed on coal-fired power plants, along with vehicle emissions, building work and factory emissions that come from 30 years of huge economic expansion.

Smog also hits China's north on a regular basis - sometimes forcing the closure of major motorways because of poor visibility.

China, the world's biggest carbon emitter, plans to cut dangerous emissions from coal-fired power plants by 50% over the next five years, and says its overall emissions will peak by about 2030 before then falling.

The country still depends on coal for more than 60% of its electricity but is in the process of shifting to solar, wind and nuclear power.