JINAN－At the command of his handler, Youxian sniffed around a gas pipe, barked and refused to budge.

The reactions were a clear sign the 18-month-old German shepherd had detected gas.

Youxian, meaning "priority", is the first sniffer dog trained in gas leak detection to be put into service in Shandong province.

The dog started working for the Jihua Gas company in the provincial capital of Jinan in mid-November, when the city's heating season began. With his supersensitive nose, he has detected four gas leaks so far.

"The point of the leak can be detected even if the pipeline is buried underground," said Liu Chengwei, senior manager of the company.

He said the company hired a team of four gas technicians and dog handler Wang Yongwei to detect leaks along its 2,800-kilometer pipeline.

If a pipe section in a certain area is old or has leaked before, it is classified as a high-risk area. As part of the regular maintenance, Youxian is sent to detect possible leaks.

"We have to get it done as quickly as possible to root out the risk of a blast, and also prevent extended suspensions of gas supply," Liu said, adding keeping up supplies to customers is crucial during the cold winter months.

Natural gas is colorless and odorless, but detector dogs can sniff it out because they have a heightened sense of smell for tetrahydrothiophene, a chemical with a strong odor added to natural gas to serve as an alert for leaks.

Liu said gas leak detection was time-consuming and costly before Youxian was put into service.

"The technicians had to use a laser methane detector along the entire pipeline. Now with Youxian, they can pinpoint the leak in a fast, accurate and cost-efficient manner," he said.

Wang has been with Youxian since the dog was trained in Xiamen, Fujian province. After residential communities in Jinan were locked down to control the spread of the novel coronavirus, Wang and the dog have been on standby, and only go out if there is an emergency.

For the dog's health, Wang disinfects the kennel with alcohol every day. Youxian will return to Xiamen for training when the heating season is over, and hopefully come back to Jinan for long-term service, Liu said.

Xinhua