Colorado announced proposed rules on Monday designed to reduce emissions during oil and gas operations in an agreement with drillers that addresses one key environmental concern surrounding the U.S. oil and gas boom.

The western state's Air Pollution Control Division proposed new regulations to reduce the release of methane during production and transport of natural gas in a deal with energy producers Anadarko Petroleum, Noble Energy, Encana Corp and the Environmental Defense Fund.

The regulations, a first for a U.S. state according to environmentalists, would require operators to perform frequent checks for leaks using infrared cameras and other technologies.

"This proposal represents a model for the nation," said Fred Krupp, president of Environmental Defense Fund.

A spokesman for Encana said the company had been testing similar technology for the past two years in Wyoming and that it had reduced emissions.

The rules come as oil and gas output in Colorado and the whole United States is rapidly increasing thanks to new drilling techniques like fracking that have unlocked vast amounts of fuel from shale rock deposits deep underground.

The drilling boom, that has pushed natural gas output to all-time highs, has brought with it concerns about the impact on the environment, including greater volumes of methane leaking into the atmosphere.

"If this package is adopted, Coloradan's will breathe easier, knowing they have the best rules in the country for controlling air pollution from oil and gas activities." Krupp said.

The rule package will be formally proposed to the Colorado Air Quality Control Commission by agency staff on November 21 and will be scheduled for hearings in February 2014. The Commission meetings are open to the public, the Defense Fund said .

Many in Colorado will need persuading. While crude oil production in Colorado rose 64% from 2007-2011, and natural gas production rose 27%, opposition has emerged against drilling techniques like fracking that involves pumping millions of gallons of chemical-laced water and sand into shale rock.

Voters in three Colorado cities passed measures to ban fracking earlier this month for fear that fracking was a danger to the environment.