Greenhouse Gas Emission Rules FAQs

Which Greenhouse Gases Are To Be Reported?
The greenhouse gases covered by the rule are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), sulfur hexafluoride (SF6), hydrofluorocarbons (HFCs), and perfluorochemicals (PFCs), and other fluorinated gases, such as nitrogen trifluoride and hydrofluorinated ethers (HFEs).

Printing facilities that exceed the reporting threshold for fuel combustion emissions would only have to report on total carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions from each fuel combustion unit would be required to be reported. For each unit, CO2, CH4, and N2O emissions would be reported separately for each type of fuel combusted. No other greenhouse gases need to be reported. 

How Do I Determine Greenhouse Gas Emissions for My Operation?
The first step is to conduct an inventory of all fuel combustion equipment along with its respective firing rate and the fuels that are burned in them. The second step is to total all of the firing rates of units by fuel burned and compare that to the relative thresholds for reporting. If the total of all firing rates are greater than 30 million mmBtu/hr, then an emission report might be required. However, if the fuel being burned is natural gas, then the threshold would increase to 50 million mmBtu/hr.  (Remember, portable equipment or generating units designated as emergency generators in a permit issued by a state or local air pollution control agency would be excluded from the inventory.)

The other option would be to actually calculate or measure the greenhouse gases being emitted and then convert them to carbon dioxide equivalents. The reporting threshold and other requirements are based on a relatively new unit of measure called carbon dioxide equivalents, which is abbreviated CO2e. This unit takes into account the relative global warming potential of each gas in relationship to carbon dioxide (CO2), which has a global warming potential of 1 and other greenhouse gases having a factor greater than 1.  For example, methane has a global warming potential 21 times greater than CO2.

To calculate greenhouse gas (GHG) emissions for comparison to the 25,000 metric ton CO2e/year emission threshold, the mass emissions of CO2, CH4, N2O need to first be determined (see below). Then, the emissions of each GHG need to be converted to metric tons CO2e per year and summed for all combustion units and fuels used at the facility.

Determining CO2e
The following formula is used to convert the emissions of all greenhouse gases to carbon dioxide equivalents:
CO2e = Carbon dioxide equivalent, metric tons/year
GHG = Mass emissions of each greenhouse gas emitted, metric tons/year
GWP = Global warming potential for each greenhouse gas
The GWP* for CO2, CH4, N2O are as follows:









Determining Greenhouse Gas Mass Emissions
In the rule, there are several approaches, called tiers, provided for determining the emissions of the greenhouse gases and they are dependent upon the type of operation and total firing rate of all of the fuel combustion units. Since most printing operations are not subject to the Acid Rain Program, have continuous emission monitors for combustion gases, and have a total firing rate of less than 250 mmBtu/hr and do not burn solid fuels, then emissions for each for each greenhouse gas can be calculated using default high heating values and CO2 emission factors. The only exception would be if there was available from the supplier a measured high heating value for the fuel being used in the combustion unit, then this would have to be used in the calculations.

The mass emissions of each greenhouse gas emitted are determined by using the following formulas:
CO2 = 1×10−3×Fuel×HHV×EF
CH4 = 1×10−3×Fuel×HHV×EF
N2O = 1×10−3×Fuel×HHV×EF
CO2 = Annual CO2 mass emissions for the specific fuel type (metric tons)
CH4= Annual CO2 mass emissions for the specific fuel type (metric tons)
N2O= Annual CO2 mass emissions for the specific fuel type (metric tons)
Fuel = Mass or volume of fuel combusted per year, from company records (express
mass in short tons for solid fuel, volume in standard cubic feet for gaseous fuel,
and volume in gallons for liquid fuel)
HHV = Default high heat value of the fuel (mmBtu per mass or mmBtu per volume, as
EF    = Fuel-specific default emission factor - CO2 (kg CO2/mmBtu), CH4 (kg CH4 per
mmBtu), N2O (kg N2O per mmBtu).
1×10-3 = Conversion factor from kilograms to metric tons

Fuel Type

Default High Heat Value*

Default CO2 Emission Factor*

Default CH4 Emission Factor*

Default N2O Emission Factor*

Natural Gas

1×10−3 mmBtu/cf

53.02 kg/mmBtu

9×10−4 kg/mmBtu

1×10−4 kg/mmBtu

Distillate Fuel Oil (#1,2,4)

0.139 mmBtu/gal

73.10 kg/mmBtu

3×10−3 kg/mmBtu

6×10−4 kg/mmBtu


0.092 mmBtu/gal

62.98 kg/mmBtu

1×10−3 kg/mmBtu

1×10−4 kg/mmBtu

* EPA’s regulation contains several charts that identify Global Warming Potentials for other gases and Default High Heat Values and Default Emission Factors for many other fuels. Only the common ones are presented in this fact sheet. See for more information.

Would a Business With a Vehicle Fleet Be Required to Report?
No. Under the rule, emissions from mobile sources would be covered by reports from fuel suppliers and manufacturers of vehicles and engines, not by fleet operators. However, EPA is taking comment on whether it is appropriate to require additional information from fleet operators.

Do the Emission Reports Have To Be Verified By an Independent Third Party?
No. Under the final rule, a separate verification is not required. The facility will be self-certifying as is the case in many other EPA required reporting rules. EPA reserved the right to revisit the third party certification in the future.In order to assure data quality, the Reporting Rule provides quality control and assurance measures for each affected sector, requires facilities to submit supporting data to EPA, and provides for EPA to verify emission figures.

What Records Would Need To Be Kept?
Under the rule, each facility and supplier would retain the following records for three years in electronic or hard-copy format:

  • A list of all units, operations, processes, and activities for which the reporter calculates GHG emissions.
  • Data used to calculate the GHG emissions for each unit, operation, process, and activity, categorized by fuel or material type. These data vary by source category and include, but are not limited to:
    • The GHG emission calculations and methods used.
    • Analytical results for the development of site-specific emission factors.
    • Results of all required analyses of high heat value, carbon content, or other required fuel or feedstock parameters.
  • Any facility operating data or process information used for the GHG emissions calculation.
  • Annual GHG reports.
  • Missing data computations. For each missing data event, also record the duration of the event, actions taken to restore malfunctioning equipment, the cause of the event, and actions taken to prevent or minimize occurrence in the future.
  • A written GHG monitoring plan. The plan can rely on references to existing operating documents (e.g., standard operating procedures, other documents), providing the following elements are included and easily recognizable:
    • Identification of positions of responsibility (i.e., job titles) for collecting GHG data.
    • Explanation of processes and methods used to collect the data needed to calculate GHG emissions.
    • Description of procedures and methods used for quality assurance, maintenance, and repair of monitoring systems used to provide data for the GHG reports.
  • The results of all required certification and quality assurance tests of monitoring systems used to provide data for the annual GHG report.
  • Maintenance records for monitoring instrumentation.
  • Any other data specified in any applicable subpart of this rule.

When Are Reporters Required to Complete Their GHG Monitoring Plan?
EPA requires that the Monitoring Plan will be developed by no later than April 1, 2010, which is the date when the full monitoring approach, will be implemented by most sources. The purpose of the plan is to document the process and procedures for collecting and reviewing the data needed to estimate annual GHG emissions. Therefore, this plan needs to be in place prior to collecting data to ensure that consistent and accurate data are collected. The plan does not have to be complex and can rely on existing corporate documents like SOPs and Monitoring Plans developed for compliance with other air programs. While some facilities may use best available methods to estimate GHG emissions for a period beyond three months (after April 1, 2010), facilities still need to have a plan developed for the basic procedures that will be used to collect data. A facility's data collection methods may change and evolve as the facility gains experience with monitoring equipment and develops more effective procedures for data management. Under the final rule, the Monitoring Plan must be revised to reflect these changes.

When Can Reporting Be Discontinued?
In order to encourage emission reductions and ensure that the reporting system only captures major facilities, the final rule was amended to allow facilities to discontinue reporting when their reports show emissions of:

  • Less than 25,000 tons CO2-e for five consecutive years, or ;
  • Less than 15,000 tons CO2-e for three consecutive years, or;
  • Cease reporting if the GHG-emitting processes or operations are shut down

Will the Public Be Able to See My Reports?  
Emissions data reported to EPA under the Reporting Rule will be made available to the public.  Other data submitted to EPA (e.g., certain production and process data) may be protected under the agency’s procedures governing confidential business information.  EPA has indicated that future rulemaking will address the question of what information qualifies as “emissions data” for purposes of GHG reporting. 

Is This Reporting Requirement the Same As A Carbon Footprint?
No. Carbon footprinting involves a much greater scope of carbon emissions than what is covered by this rule. There are actually two separate carbon footprints that can be determined with one focusing on the product and the other on the printing operations. While there could be some overlap between the two, there are also distinct differences.

Regarding the carbon footprinting of printing operations, there are several different protocols being used with the World Resources Institute and the World Business Council for Sustainable Development ( being commonly adopted by newspapers. The other two common protocols are EPA's Climate Leaders program ( and the Climate Registry (
While there are differences between the protocols, they all require the counting of carbon from direct sources (fossil fuel combustion), indirect sources such as electricity purchasing, and optional sources such as transportation due to business such as airline travel, company and other delivery vehicles, employee commuting, etc. The EPA rule only requires emission reporting from the direct combustion of fuels. 

How Does This Requirement Impact State Greenhouse Gas Reporting Rules?
This regulation is separate from any state requirement. Since states can implement their own greenhouse gas emission reporting programs, many have done so and they usually have lower thresholds and different requirements with respect to data verification. For example, Massachusetts has a reporting threshold of 5,000 tons of CO2-e and other states require any company with a Title V Operating Permit to submit annual emission information. For an interactive map of the state’s greenhouse gas emission reporting requirements see EPA also has an interactive map, which can be found at

Where Can I Get More Information?
More information on EPA's greenhouse gas reporting rule is available at

Published on Tuesday, June 14, 2011 (updated 05/30/2014)

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