US requires oil, gas firms to report carbon output

* EPA forcing industries to monitor and report emissions

* Emissions monitoring, reporting to start next year

WASHINGTON Nov 9 (Reuters) - U.S. environmental regulators finalized rules requiring oil and natural gas plants to monitor and report all their greenhouse gas emissions beginning next year.

The oil and gas industries release carbon dioxide and other greenhouse gases. Combined, the industries are one of the largest human-related emitters of methane, which is about 20 times more potent a greenhouse gas than carbon dioxide, the EPA said.

The new rules add those industries to the EPA's greenhouse gas reporting program that started this year.

Beginning on January 1, 2011 oil and gas facilities that emit more than 25,000 tonnes per year of carbon dioxide equivalent must monitor and report data on their greenhouse gases to the EPA.

Starting in March 2012, companies will have to issue annual reports on their emissions.

They will not have to reduce emissions through the program, but they could be required to in coming years.

Industry groups opposed the move. "As proposed, this rule would have defined 'facility' in an unworkable manner and imposed unreasonable reporting obligations on tens of thousands of oil and gas operations," the American Petroleum Institute said in a release.