The US Environmental Protection Agency (EPA) has issued the Final Mandatory Reporting of Greenhouse Gases Rule. The rule requires reporting of greenhouse gas (GHG) emissions from large sources and suppliers in the United States, and is intended to collect accurate and timely emissions data to inform future policy decisions.

Under the rule, suppliers of fossil fuels or industrial greenhouse gases, manufacturers of vehicles and engines, and facilities that emit 25,000 metric tons or more per year of GHG emissions are required to submit annual reports to EPA. The gases covered by the proposed rule are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFC), perfluorocarbons (PFC), sulfur hexafluoride (SF6), and other fluorinated gases including nitrogen trifluoride (NF3) and hydrofluorinated ethers (HFE).

The rule requires large emitters of heat-trapping emissions to begin collecting greenhouse gas (GHG) data under a new reporting system beginning 1 January 2010. This new program will cover approximately 85% of US GHG emissions and apply to roughly 10,000 facilities.

The first annual reports for the largest emitting facilities, covering calendar year 2010, will be submitted to EPA in 2011. Vehicle and engine manufacturers outside of the light-duty sector will begin phasing in GHG reporting with model year 2011. Some source categories included in the proposed rule are still under review.