Beijing So what does orange mean – one shade less than red! It’s all about air quality. How bad is the air in Beijing today? More than nine times World Health Organization recommended levels.

Beijing raised its air pollution alert to orange as smog levels were projected to stay hazardous this weekend, triggering orders for some enterprises to limit production and a ban on outdoor barbecues and fireworks.

Drivers were asked to reduce vehicle-use and take public transport, while the elderly and children were advised to stay indoors. The concentration of PM2.5, fine particulates that pose the greatest risk to human health, was 237 micrograms per cubic meter at 3 p.m. near Tiananmen Square in Beijing, the Beijing Municipal Environmental Monitoring Center said on its website.

The orange alert is part of a new pollution monitoring plan announced in October to help cope with heavy air pollution, with alerts from the most serious to less serious tagged red, orange, yellow and blue. The city upgraded its alert from yesterday’s yellow warning that called for measures such as increased road cleaning and spraying of water at construction sites.

http://www.businessweek.com/news/2014-02-20/beijing-issues-yellow-alert-with-three-days-of-smog-forecast