China has completed a 500-meter underwater land-based saturation diving experiment, according to the Ministry of Transport on Tuesday.
It marks China's progress in the development of such technology, Wang Lei, director of rescue department of the Ministry of Transport, told an online news conference on Tuesday in Beijing.
China had been conducting saturation diving tests since 1970s. In 2014, it successfully sent divers 313.5 meters undersea, he added.
The most recent experiment started on May 22, when nine divers from the Shanghai Rescue Department entered a pressurized cabin. On May 27, the pressure was increased to a level equivalent to 500 meters underwater. Participants stayed in that high-pressure environment for 176 hours and carried out several experiments.
Divers returned to normal pressure and walked out of the cabin on June 25. After three weeks of monitoring and observation, the participants were deemed physically and mentally healthy.
Saturation diving, commonly used in rescue operations at sea, enables rescuers to work at greater depths underwater for a longer period of time while reducing the risk of decompression sickness, compared with conventional techniques.
Wang said the next step is to carry out a 500-meter underwater saturation diving experiment in a real undersea environment.
This year marks the 70th anniversary of China's Search and Rescue Department. Since its establishment, the team has rescued 82,783 people stranded at sea. Among them, 12,703 have been foreigners.
