Beijing issued the "yellow alert" for air pollution today for the second time this month as the Chinese capital remained blanketed by heavily-polluted haze, forcing city residents indoors.

 

The fine particulate matter PM2.5 touched 304 micrograms per cubic metre on Saturday, which is regarded very unhealthy specially for people with heart and lung problems, according to the air quality index of the US Embassy here.

 

National Meteorological Centre advised city residents to take protective measures, and asked those with respiratory problems to reduce outdoor activities.

 

The NMC issued the "yellow alert" - the third-most serious level in a four tier colour-code warning system. Red is the most serious and orange the second-most serious while blue is the least serious pollution level.

 

This was the second time this month that Beijing issued a "yellow alert" after October 2.

 

The meteorological authorities issue alerts when the AQI reaches 200 and severe air pollution is forecast to last at least one day.

 

On Friday, the smog decreased visibility to within 500 metres in some parts of Beijing.

 

Meteorologists expect North China to see more smog in autumn and winter, given unfavourable weather conditions this year, Xinhua News Agency reported previously reported.

 

Despite Beijing's attempts to limit air pollution, the capital saw only 186 days with air quality that met the national standard in 2015, which means air pollution cast shadows over Beijing for nearly half of the year, a report in the state-run Global Times said.

 

The city was also shrouded with heavy air pollution for 46 days, or 13 per cent of the year, said the local environmental protection bureau. (The Economic Times)