Failure to aim properly will see users of public toilets in a southern city targeted with fines from September.

The regulation in Shenzhen, Guangdong province, which has been approved by the city government and takes effect on Sept 1, stipulates that improper behavior, such as painting and engraving on walls, spitting, littering and smoking, will invite a fine of 100 yuan ($16.30).

The regulation also targets those who aim poorly when urinating or defecating.

Not surprisingly, the regulation has sparked intense debate, and many residents expressed doubt about just how exactly the regulation will be enforced.

"This clause is ridiculous," said Gao Qiao, 24, a university student in Shenzhen. "How will people, who drafted the regulation, enforce it? And if you are not able to implement this rule, how can it meet its goal?"

A Sina Weibo user in Shenzhen, who goes under the name Qiaoninabenyang, also expressed doubts.

"It is inevitable that people will make some unintentional error when using the toilet. A little spillage outside the bowl doesn't necessarily mean the person intended to make trouble.

"It is biology. Nobody practices a detailed procedure for urinating."

Zhu Rui, a tourist from Chengdu in Sichuan province, said: "I think most parts of the regulation are understandable.

"But it is totally impossible to enforce it unless you place someone in the restroom to monitor those who use it, which is weird and unacceptable."

Li Zhiyong, a Shenzhen lawyer, told Guangzhou Daily that public restrooms are a place where people have, and expect, privacy so it is completely unrealistic for law enforcement officers to check whether a person is violating the regulation.

"Instead of resorting to regulatory means, the government can promote public awareness on 'toilet manners'."

Gao and Zhu suggested that authorities should shift priority and unveil more toilet facilities for the public to combat a huge shortage.

The government is fully aware about complaints concerning the difficulty in finding public toilets, local officials said.

But the regulation addresses this to some extent, they added.

It wants urban management authorities to sign contracts with social organizations or businesses to invest in toilet facilities.

It also urges urban planning and construction departments to build more restrooms in public places and government buildings.

Chen Wenli in Shenzhen contributed to this story.