Using Cal e-GGRT to Prepare Your Subpart N Report
Note: The Cal e-GGRT help system includes general instruction on using the California GHG reporting tool. However, the help system may not explain differences between California and U.S. EPA reporting requirements. Please refer to the ARB reporting website for California-specific reporting requirements and additional help.


This page provides an overview of subtopics that are central to Subpart N reporting. This information will be entered from the Cal e-GGRT Subpart N Overview web form shown below. Each topic represents a key web form where you need to enter information:

The end of this overview page provides links for more detailed information and instructions on entering required information related to each of these topics.

Subpart N Summary Information for this Facility

Subpart N requires you to report the following data about your facility:

  • The total number of continuous furnaces in your facility used to produce glass
  • The total annual quantity (short tons) of glass produced across all continuous glass melting furnaces in your facility

Cal e-GGRT WILL calculate these two values based on information you entered for individual furnaces. So, again, you do not need to complete this field; Cal e-GGRT will automatically populate these fields as you complete other forms. Just be sure to check the value before you submit your Subpart N report.

Subpart N also requires you to report:

  • The total annual quantity (short tons) charged across all continuous glass melting furnaces of the following carbonate-based raw materials. Enter “0” for those carbonates not consumed or used in producing glass at your facility for the reporting year:
    • Limestone
    • Dolomite
    • Sodium carbonate
    • Barium carbonate
    • Strontium carbonate
    • Lithium carbonate
    • Potassium

In addition, §95116 requires you to report:

  • Annual quantity of fiberglass pulled from the facility
  • Annual quantity of container glass pulled from the facility
  • Annual quantity of flat glass pulled from the facility

Subpart N Furnace Information

For each furnace at your facility, Subpart N requires you to report the following information:

  • A unique name or identifier, plus optional description for this furnace (see also About Unique Unit Names)
  • The total annual quantity (in short tons) of glass produced by this furnace
  • An indication of which of the carbonate-based raw materials (limestone, dolomite, sodium carbonate, barium carbonate, strontium carbonate, lithium carbonate, and potassium carbonate) are charged to this furnace

Subpart N Emissions Information

The required emissions information and the forms associated with entering the required emissions information are different for units that are monitored by a Continuous Emissions Monitoring System (CEMS) and units that are NOT monitored by a CEMS.

As a result, the help content for entering emissions information for units monitored by CEMS is different than the help content for units NOT monitored by CEMS.

For each glass melting furnace that is NOT monitored by CEMS at your facility, the following information is required:

  • The CO2 process emissions (metric tons)
  • For each raw material charged to each continuous glass melting furnace:
    • The number of months during the reporting year that missing data procedures were followed to estimate monthly quantities for the raw material
    • The method you used to determine the fraction of calcination for the raw material (Default Value of 1.0, Chemical analysis using x-ray fluorescence, or Other)
    • The number of months during the reporting year that missing data procedures were followed to estimate mass fractions for the raw material
  • For each test conducted to verify the mass fraction:
    • The test date. If you choose to use the default as an alternative to supplier data as explained in 98.143(c)) enter any date (e.g. Dec. 1, 2010).
    • The method(s) and any variations used in the analyses. If you choose to use the default as an alternative to supplier data as explained in 98.143(c)) enter “Default Method per 98.143(c)” for method.
    • The mass fraction values for all test samples recorded during the test. If you choose to use the default as an alternative to supplier data as explained in 98.143(c)) enter “Default Method per 98.143(c)” for method and enter 1.0 for mass fraction of sample.

For each process unit that is monitored by CEMS at your facility, the following emissions information is required:

  • The annual quantity of each carbonate-based raw material charged into the glass melting furnace (short tons)

For each CEMS Monitoring Location, provide the following information:

  • A unique unit name or identifier for the CML (see also About Unique Unit Names)
  • An optional description or label for the CML
  • The configuration of processes or process units that are monitored by the CML:
    • Single process or process unit that exhausts to a dedicated stack
    • Multiple processes or process units that share a common stack
    • Process or process unit that shares a common stack with one or more stationary fuel combustion units
  • The name of each fuel combusted in the unit(s) monitored by the CEMS
  • The Tier 4/CEMS methodology start and end dates
  • The cumulative total of hourly CO2 mass emissions for each quarter of the reporting year (metric tons) (Do not cumulate emissions data between quarters)
  • The total annual CO2 mass emissions measured by the CEMS (metric tons)
  • An indication whether emissions reported for the CEMS include emissions calculated according to 98.33(a)(4)(viii) for a slipstream that bypassed the CEMS
  • The total annual biogenic CO2 emissions from the combustion of all biomass fuels combined (metric tons) (if not applicable, enter '0')
  • The total annual non-biogenic CO2 emissions which includes fossil fuel, sorbent, and process CO2 emissions (metric tons)
  • The total annual CH4 and N2O emissions associated with the combustion of all Table C-2 fuels combusted in all processes/process units monitored by the CEMS derived from application of Equation C-10 (metric tons) (if there are no combustion emissions in this CML, please enter '0')
  • The total number of source operating hours in the reporting year
  • The total operating hours in which a substitute data value was used in the emissions calculations for the CO2 concentration parameter
  • The total operating hours in which a substitute data value was used in the emissions calculations for the stack gas flow rate parameter
  • If moisture correction is required and a continuous moisture monitor is used, the total operating hours in which a substitute data value was used in the emissions calculations for the stack gas moisture content parameter
  • An indication of the process units monitored by the CML

Subpart N Validation Report

You can use the Validation Report to ensure the completeness and quality of your reporting data.

You should use the Validation Report to check your work. The Validation Report performs two types of checks:

  • Data Completeness: Data that are required for reporting is missing or incomplete.
  • Data Quality: Data are outside of the expected range of values.

You may view the Validation Report at any time.

Note that the Validation Report is intended to assist users in entering data, but it is not an indication that the reporter has entered all necessary information, nor is it an indication that the reporter is in compliance with 40 CFR Part 98. Furthermore a negative finding on the validation report is not a guarantee that a data element was entered incorrectly.

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See Also

Screen Errors
Subpart N Summary Information for this Facility
Subpart N Furnace Information
Subpart N Emissions Information for Furnaces NOT Monitored by CEMS
Subpart N Emissions Information for Furnaces Monitored by CEMS
Subpart Validation Report

This web site is maintained by a contractor to the California Air Resources Board (RY2015.R.03)