The Colorado Department of Public Health and Environment has proposed new rules to require the reporting of greenhouse gas emissions and the reduction of one such category of gases, known as hydrofluorocarbons.

The state’s Air Quality Control Commission, which heard the proposals on Thursday, will schedule a formal rulemaking meeting for May 21.

“About a year ago, Governor Polis gave us the directive to be bold in protecting the health of our communities and the Colorado environment by reducing greenhouse gases, and we have been running with that directive,” said Jill Hunsaker Ryan, the department’s executive director.

The emissions-reporting rule would add to the requirements for the oil and gas industry by also covering industrial solid waste landfills, wastewater treatment facilities, active underground coal mines, and importers and exporters of liquid fossil fuels.

Senate Bill 19-181 required the commission to adopt rules to minimize emissions of methane, volatile organic compounds and other hydrocarbons.

Hydrofluorocarbons – which are common in refrigeration, air conditioning and aerosol propellants – would be phased out. The department based its proposal on model rule from the U.S. Climate Alliance, which is a bipartisan group of governors who would like to adhere to the principles of the Paris Agreement. President Donald Trump withdrew the United States from the international framework for controlling greenhouse gas emissions.

The department estimates that its new hydrofluorocarbon rule would prevent 6.3 million metric tons of emissions by 2030.