China is the second largest crude oil consumer in the world, according to the International Energy Agency (IEA).

In 2006, China National Offshore Oil Corp (CNOOC), one of the biggest oil companies in the country, found the first offshore deepwater natural gas well in the South China Sea and two more in the same region between 2009 and 2010. The company plans to expand oil-gas exploration between 2015 and 2020.

Some 60 percent of oil and gas fields with reserves of more than 100 million tons found in the last decade are in the ocean, according to Zhou Shouwei, deputy general manager of CNOOC and an academic with the Chinese Academy of Engineering.

"The deep ocean is where the future exploration for oil and gas will focus," he was quoted as saying by Xinhua News Agency.

"But deep-water drilling is very complicated and no country or company is able to master all of them," he said. "Strictly following the techniques and operation rules is the fundamental way to prevent accidents from happening."

Li Yan, a research fellow at the China Institute of Contemporary International Relations, said the oil spill disaster in the Gulf of Mexico should be a warning to highlight the vulnerability of the marine ecosystem and to coordinate maritime development and ocean governance.

"China is accelerating all types of marine development. More marine drilling provides more energy that the economic growth needs, and more oil transport on the sea increases the probability of marine pollution," said the researcher.

Marine conservation awareness in China lags far behind ocean exploitations, Li said.

Therefore, the Chinese government and industries must pay more attention to protect the sea ecobiology for long-term development, Li warned.

The number of oil spill cases has reached 500 each year as China has become the second largest oil importer with 90 percent of imported oil shipped on the sea, according to Zheng Binghui, vice-president of the China Research Academy of Environmental Sciences.

The oil content in some of China's coastal sea waters was two to eight times more than the national standard for sea water that humans would possibly touch, said Bao Xianwen, a professor at Ocean University of China in Qingdao, Shandong province. The national standard is 0.05 mg/l.

"This means that China's sea water quality has become a serious problem," Bao said.

The Dalian incident happened at a 15-million-ton-capacity port located in Liaodong Peninsula in the Yellow Sea, not far from Bohai Sea. In the region, thousands of offshore drilling platforms are running to exploit oil.

The port, the largest deepwater petroleum port in the country, is a crucial interchange site for crude oil from Daqing, Heilongjiang province, shipped to many regions of China and other countries. It also functions as a port to receive raw oil imported to supply energy for domestic industries.

The Friday blast happened when a Liberian oil tanker offloaded raw oil, according to Luo Lin, minister of State Administration of Work Safety.

Residents and experts agreed: China needs to sort out how to manage and protect the ocean and its coastline.

"The management of ocean is split among the departments of ocean, fishing, environmental protection, maritime transportation, custom and frontier defense," Li said. "Too many departments are involved, and no one will take the responsibility."

Also, coastal provinces are in charge of the region within their territory. "This hampers the efficiency of the comprehensive management of the ocean," Li added.

Offshore drilling is considered a high risk for oil companies in the United States and United Kingdom, where such technologies are at an advanced level. In China, where the technologies and management are less developed, more accidents could happen.

Professor Zheng said the supervision of local work safety authorities should be strengthened to avoid the potential risk of oil spills.

"Oil companies and port-managing departments should also check all sectors of oil drilling and shipping to reduce the possibility of oil spills," Zheng said, adding that emergency response plans should be made and practiced so that staff could properly handle the dangers.