China mulls first light pollution control regulation

Teaching astronomy in a busy metropolis where the starry night sky is often obscured by light pollution is no easy task, especially as, generally, people are unaware of the health and social problems incessant illumination can have.

In his role as with the Guangzhou youth science and technology education association in south China's Guangdong Province, one of Han Yan's main tasks is to lead students observing the night sky.

"Our work is really affected by light pollution," he lamented, "meaning we have to travel to the suburbs to get a really clear view of the stars."

Hoping to address this problem, Han, who is also a member of the Guangzhou Municipal Committee of the Chinese People's Political Consultative Conference (CPPCC), submitted a light pollution control proposal to the local government at the beginning of this year.

Much to his delight, the Guangzhou environmental protection bureau issued a draft regulation on light pollution, which was published on Nov. 17. It is currently at the public consultation stage.

The draft covers initiatives such as the thickness of glass panels on buildings, the illumination of roads and neon lighting.

According to the draft, buildings within 100 meters of residential areas may not install glass on the sides facing residences, and outdoor advertisements and signs with LED screens should be turned off from 10:30 p.m. to 7:30 a.m.

Should the draft be passed, it will be China's first piece of local legislation on light pollution.

Zhou Yongzhang, professor with Sun Yat-sen University in Guangzhou, said the light reflected by huge installations of glass can damage the photoreceptor cells of the retina and may result in road accidents.

Brightly lit advertisements that remain turned on at night may disturb people's body clocks or affect their sleep, he said.

In fact, Zhou said, light pollution can be more harmful when combined with air pollution.

"Light can decompose and synthesis with pollutants in the air such as PM2.5, forming new pollutants. This secondary pollution can be even more detrimental to human health," he said.

According to the Guangzhou environmental protection department, the city's police received 34 complaints relating to light pollution between 2009 and 2013, and this rose to 70 between January 2013 and March 2014. The complaints were mainly related to road illumination and advertisement.

Director of the Guangzhou Research Institute of Environmental Protection policy research center, Li Mingguang, said light pollution has come to the fore in recent years in big cities such as Beijing, Shanghai and Nanjing.

The government of Nanjing issueed a guideline on lighting of urban landscapes, which limited or prohibited lighting projects in certain areas.

Li, however, said as studies on light pollution were still in their infancy there was no specific legislation on light pollution, yet.

Guangzhou's legislation, Han Yan said, is a significant step, despite it having flaws.

"For example, there is no restrictions on the brightness of light, the spectra patterns or the installation standards. Nevertheless, since currently there are no technical standards regarding light pollution, it is understandable," he said.

The real test will come after the regulation is brought into effect, Zhou Yongzhang said, as effective implementation will be "a hard nut to crack".

Light pollution is still largely misunderstood by China's academic circles and the general public. Besides regulations, more effort is needed to mobilize social forces to stand up against light pollution, he added.