A restaurant in China has been caught charging its customers a fee for breathing in clean air. Diners are being charged one yuan ($0.15, £0.10) extra towards air purification fee.

The restaurant in eastern China's Zhangjiagang city started charging the fee after it installed an air purifier, China's Xinhua news agency reported. The restaurant owner allegedly tried to compensate for the equipment's cost through the pollutant-free air fee.

The report said the service fee was illegal as air could not be sold as a commodity. Moreover, the restaurant owner did not inform diners about the new equipment. It was not the choice of diners to breathe in filtered air. The choice was imposed, instead, a city official told the news agency.

The restaurant has been charging its guests since Beijing issued its first ever red alert for air pollution early this month. The three-day highest smog alert was issued on 7 December as it posed hazardous threats to public health and to reduce the degree of air pollution.

A BBC report said Zhangjiagang city in Jiangsu Province has also been witnessing thick smog in recent weeks. In that case, the restaurant's move has been positively received by some. The report said Chinese social media users expressed their support for the restaurant's idea on the Sina Weibo microblogging site, saying they will be happy to pay for breathing in pollution-free air.

"I'd agree to the fee!" BBC quoted one as saying on Weibo. There are others who think that the restaurant owner should have, at least, prompted customers about its new service fee. "Paying is not the problem. The problem is being informed in advance and obtaining consent," a user wrote, according to the report.

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