A nationwide overhaul of oil pipelines launched after a fatal explosion in Qingdao, Shandong province, has found hazards in many areas that could lead to similar incidents, according to the country’s top work safety watchdog.

The overhaul was launched after oil leaked into sewage pipes where it exploded to kill 62 people in Qingdao on Nov 22, and has detected faults such as aging pipes and overlapping pipelines for oil and sewage, said Huang Yi, spokesman for the State Administration of Work Safety.

"Some of the problems are staggering and some hazards are found everywhere," he said, adding that many oil pipelines are more than 40 years old and suffer from erosion and weakening.

The country currently has more than 655 oil lines in service, measuring 102,000 kilometers in total.

Wang Haoshui, an inspector with the watchdog who is in charge of petrochemical work safety, said the inspection covered nearly 3,000 petrochemical companies and oil storage facilities and has revealed nearly 20,000 potential hazards.

The watchdog has ordered all the potential dangers to be rectified, he said.

Huang said an official inquiry into the oil pipeline explosion has found the State-owned oil giant Sinopec and local government both liable for the accident for failing to conduct proper safety checks and overhauls in the section that led to the explosion.

Huang said the inquiry has identified the explosion as a "responsibility accident" and the results will be made public after a review by the State Council.

The explosion occurred after oil leaked from a corroded pipe into the urban sewage network. The crude oil became mixed with the air inside the sewage system and the resulting gas quickly spread to other sections of the sewage network.

Meanwhile, emergency workers failed to identify the potential for an explosion and used a hydraulic hammer that wasn’t explosion-proof, producing the sparks that triggered the blasts.

More than eight hours after the oil leak, both the company and the government failed to identify the potential danger and failed to block roads and evacuate people from the area, Huang said.

The inquiry also found that urban planning in the explosion area was "very chaotic", with the oil pipeline located "too close to the residential areas" and the pipelines overlapping the urban sewage pipes.

"Both the urban planning and the urban administration authority must be held responsible," he said.

Huang said the watchdog will also step up supervision of State-owned enterprises this year in response to the large number of safety accidents that occurred in SOEs last year.

"There are still problems in the way SOEs manage their companies that operate at lower levels. There are also many hierarchies within the SOEs, which means there is more subcontracting of projects, which makes safety supervision more difficult," he said.

Xie Chuanjiao in Qingdao contributed to this story.

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