A restaurant in eastern China has started capitalising on heavy pollution in the country. An eatery in Zhangjiagang city, Jiangsu Province, has been caught charging customers an "air cleaning fee" on their food bills.

South China Morning Post reported that patrons at a restaurant in Zhangjiagang city got angry when they were handed a bill that included air purification fee without warning. Customers at the restaurant were charged one yuan ($0.15 or HK$1.2) for each diner to cover the cost of purifying the air inside the restaurant.

The restaurant owners recently purchased several air filtration machines to improve the dining experience, and passed the operating cost to customers without prior warning, BBC reported. The customers complained to the city officials and the officials launched an investigation of the restaurant.

The city officials ordered the restaurant to fix its pricing system. The local government said that charging the diners for air cleaner is illegal. The city officials said that it wasn't the diners' choice to breathe filtered air, so the air could not be sold as a commodity.

The city's consumer pricing bureau said that the supply of clean air was the responsibility of the restaurant management, and should not be charged to the diners.

However, the charge was supported by many Chinese social media users. Many Chinese social media users said they would happily pay one yuan to be able to breathe easily. On Sina Weibo microblogging site, the Chinese version of Twitter, many users wrote that they would agree to the fee.

Another social media user said that there is nothing wrong with the extra fee. The restaurant owners could have added the extra one yuan to the price of the dishes, but they didn't. The kind of dining experience decides the kind of pricing.

One user said that the government should follow suit to deal with the country's smog problems. Air pollution in China has reached an all-time high with its capital, Beijing, issued its first red alert for smog last week. Some areas have been enveloped in thick smog in recent weeks with visibility of less than 100m.

But a cold wave will likely clear up smog in Beijing later Monday, Bloomberg reported. Beijing issued its lowest level blue pollution alert on Saturday evening, predicting hazardous air quality to hover for 24 hours.

Beijing Municipal Environmental Monitoring Center reported the level of PM2.5 - particles in the polluted air considered the most dangerous to people's health - was 267 micrograms per cubic meter on Monday. The WHO cautions against 24 hour exposure to PM2.5 at levels higher than 25.