OREANDA-NEWS. February 15, 2013. China will soon publish cleaner standards for automotive diesel, spurred by weeks of smoggy skies in Beijing and other major cities, but the cleaner fuel won't become compulsory for about two years, according to an emission expert and an industry newspaper.

Once the new standards are issued, oil firms will start producing diesel with a sulfur content of 50 parts per million (ppm) -- similar to Euro IV standards -- versus the prevailing national III with a sulfur content of 350 ppm, effectively reducing pollutants like sulfur dioxide and oxynitride.

The new specifications won't become a mandate across the country until the end of 2014, leaving a window of about two years, China Petrochemical News reported.

The decision follows an emergency meeting last week of government agencies, including the Ministry of Environmental Protection, pricing authorities and oil firms.

"The new diesel standards were drawn earlier but not published. The recent worsening of air pollution has quickened the release, which will be out very soon," said Tang Dagang, a vehicle emission expert with China Research Academy of Environmental Science, which is affiliated with the environment ministry.

The exact timing of the expected release of the new standards was not clear.

Diesel, a bellwether fuel of China's manufacturing-focused economy, makes up about 37 percent of China's oil market, the world's largest after the United States.

Automotive diesel, used by trucks and coaches, forms just over half of China's total diesel market of about 3.6 million barrels per day. Emissions from lower-quality diesel are among the main culprits for urban air pollution.

To motivate oil firms to quickly supply cleaner diesel to the market, the government will allow a price premium in China's grade IV diesel versus III, said Tang, adding that the government is also considering tax incentives for the next cleaner fuel, national standard V.

China introduced cleaner gasoline standards around late last year, with oil firms now marketing national IV gasoline outside of large metropolitan areas to meet a national mandate by the end of 2013. Gasoline makes up roughly 20 percent of China's oil market.

China first launched its automotive diesel specifications -- of national III standards -- in January 2010, which became a national mandate from June 2011.