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Emissions Inventory
General Instructions

Instructions for DEQ Form #100-730

Revised 1/20/2016

    1. General Reporting Guidance   4. Emission Unit Information 6. Emission Process Information
    2. Company Information   5. Emission Release Point Information     6.1 Design Ratings & Fuel Combustion Data
    3. Facility Information     5.1 Stack Parameters     6.2 Temporal Operating Information
        3.1 Facility Location     5.2 Fugitive Release Parameters 7. Emissions Information 

The Air Quality Division of the Oklahoma Department of Environmental Quality requests emissions inventories and supporting documentation required by the Federal Clean Air Act, in conjunction with Sections 2-5-105(19) and 2-5-112.B.11 of the Oklahoma Clean Air Act, Oklahoma Statutes Title 27A, and OAC 252:100-5 ("Subchapter 5").


Subchapter 5 requires potential sources of air contaminants to register with the Division, file an emissions inventory and pay annual operating fees. The owners or operators of permit exempt facilities or de minimis facilities, as these terms are defined in OAC 252:100-7-1.1, are not required to submit an annual emission inventory.

The owner or operator of a facility registered after December 31, 2014 under a permit by rule (PBR), as in OAC 252:100-7-9, shall submit an initial emissions inventory. After the initial emission inventory submittal, PBR facilities will be required to submit an annual emission inventory on the following schedule:

  • For PBR facilities with actual emissions greater than 5 tons per year of any regulated air pollutant, an emission inventory is required for every NEI Three-Year Cycle Inventory year (defined in 40 CFR Section 51.30(b)).
  • For PBR facilities with actual emissions of 5 tons or less per year of any regulated air pollutant, an emission inventory is required for every second NEI Three-Year Cycle Inventory year (defined in 40 CFR Section 5130(b)) beginning with the 2020 NEI reporting year.

Use these instructions to complete an annual facility inventory for a reporting year.


Review the accuracy of all pre-populated fields and strike through or update incorrect data and make corrections as needed. All data fields must be reported if applicable or else indicated as not applicable to the facility or operations. There are no "optional" data fields.



Report Regulated Pollutants Only. Report the amount of actual emissions of all regulated air pollutants, including quantifiable excess emissions. The following questions should be asked in the order shown to determine the correct reporting category for an emission and so avoid double counting. Once a question can be answered with a ‘yes’, then the pollutant is reported under that category only, and no more questions need be asked.

           Is the emission:
  1. A Hazardous Air Pollutant (HAP) or any other type of federally regulated pollutant (e.g., Dioxins/Furans)? These are the specific compounds and compound groups defined in the federal Clean Air Act and associated regulations. All currently regulated State Toxic Air Contaminants except ammonia are also HAPs.
2. Ammonia (NH3)?
3. One of four totally reduced sulfur compounds: hydrogen sulfide, methyl mercaptan, dimethyl sulfide, or dimethyl disulfide?
4. Sulfuric acid?
5. A pollutant not listed in Appendix P of OAC 252:100 but for which emissions are limited in the Specific Conditions of a current permit? (For more information see
6. A criteria pollutant or a volatile organic compound (VOC)?

If the emission does not fall into any of the above categories the emission is not a regulated pollutant and should not be reported.

Speciation and Reporting of Particulate Emissions is Dependent on Particle Size:

PM-10 means all particulate matter with an aerodynamic diameter of 10 micrometers or less (i.e, fine and coarse particle fractions combined).


PM-2.5 means all particulate matter with an aerodynamic diameter equal to or less than 2.5 micrometers (i.e., the fine particle fraction). PM-2.5 is a subset of PM-10. PM-2.5 can be less than or equal to, but never greater than, PM-10. Both pollutants must be reported. Note that all Condensable PM is assumed to be in the PM-2.5 category.


TSP – Do Not Report (Unless emissions are limited by the Specific Conditions of a permit). Particles ranging in size from 0.1 micrometers to about 30 micrometers in diameter are referred to as total suspended particulate matter (TSP). TSP includes a broad range of particle sizes including fine, coarse, and supercoarse particles. TSP is the total of all particulate emissions, is not subject to a fee, and should not be reported.

Note: Oklahoma DEQ does not distinguish between Condensable and Filterable PM. All Primary PM must be reported using the above categories.

Do not double-report HAPs. A regulated pollutant that is particulate matter and is also a HAP should be reported as the specific HAP only. HAPs should be speciated and reported separately where possible. They should not be also reported under the broader PM category. The reported total amounts of PM-10/PM-2.5 should be adjusted (reduced) as necessary. Following the above procedure will ensure that HAP emissions are not counted twice in the fee process.

Combining Emission Units. Some facilities have a large number of small emission units, which collectively have reportable emissions. In specific cases it is not necessary to track all these individual units but discounting them completely may result in overall emissions being underestimated. The Department believes a potential solution to this is to combine these small sources into one source. Total emissions will be reported, but the other data, such as process rates and operating hours can be averaged for the individual sources. Sources should be combined into logical groupings. For example, all of the small sources at one process unit or building could be submitted together. Contact the Emissions Inventory Section prior to grouping or combining emission units and processes.

Emissions Caps. A facility may have a facility-wide cap or an emission unit group cap. Although the method of demonstrating compliance with the cap is addressed in the permit, each emission unit must be reported separately and individually.

Lower Reporting Cut-off. A lower cut-off or minimum amount of emissions of an individual pollutant that should be reported is not defined by rule. If during normal operation, emissions are 0.1 tons or greater of any regulated air pollutant at a process, then the emissions must be reported. The key exceptions that must still be reported at 0.001 tons or greater per process are:

  • Lead, mercury & hexavalent chromium
  • Any HAP at a TRI facility
  • Any HAP from glycol dehydration still vents
  • Any HAP from large storage tanks (>500 BBL)
  • Other situations where deemed necessary

The trace checkbox can be used to indicate that emissions of a regulated pollutant have been estimated to be less than 0.001 tons per year.

In cases where there are multiple similar units (e.g. emergency generators) that individually are below the reporting threshold, but collectively above the threshold, then these units must be reported. They may be reported separately or grouped into one emission unit. If grouped, the emission unit name should include the number of units being combined. The process rate and emissions should account for the total from all individual units. The hours and design capacity should be reported as the average. An emission unit note can be added to further clarify the number of units being combined and the individual design capacities (if applicable). When grouping units, report the release point as a fugitive, with the total area of all of the units and the average height.

If in normal operations, all pollutants at a process are lower than 0.1 tons and are not one of the above key exceptions then the company may request that the emission unit be deleted from the inventory. The company must add a facility note for these situations stating why the emission unit is not being reported. If in normal operations, any individual pollutant falls below the threshold, but some pollutants are still above the threshold, the company may request that individual pollutant be deleted. The company may add an emission unit note stating why the pollutant is no longer being reported.

Change in Ownership or Company/Facility Name. The owner or operator of any facility that is required to submit an emissions inventory shall notify the Department in writing no later than 10 days following any transfer of ownership. Also, the Department should be notified in writing of any company or facility name change amount of the actual emissions, including quantifiable excess emissions.

Confidential: Indication of confidentiality of process information. Emissions data that may be held as confidential is certain information, which if made public, would divulge methods or processes entitled to protection as trade secrets. Confidential information must be severable and “CONFIDENTIAL” should be marked on every applicable page. A “PUBLIC” copy of the report should also be provided with all of the confidential information removed. The Department shall hold and keep as confidential any information declared by the provider to be a trade secret and may only release such information upon authorization by the person providing such information, or as directed by court order.

Emissions Information that may be held as confidential includes in part the following:

  • Process rates
  • Process material data
  • Process flow diagrams
  • Trade secrets and other information that may reveal trade secret processes or methods of manufacture or production.


Emissions Information that may not be held as confidential includes in part the following:

  • Emission unit type
  • Control equipment type
  • Days/week, weeks/year and hours/year of operation
  • method of calculation and other items related to the calculations and subsequent modeling analyses, “in so far as these data elements are necessary to calculate emission data.”

Due Date. All content, necessary information and requested data must be submitted by April 1 for an emissions inventory to be considered complete. Upon receiving a written demonstration of good cause the Director may grant an extension for submittal beyond the April 1 deadline.

Certification by Company Responsible Official. The emissions inventory shall contain a certification by a company responsible official (as defined in OAC 252:100-1-3) of the truth, accuracy, and completeness of the document, as required by OAC 252:100-5-2.1(f). This certification shall be signed by a responsible official and shall contain the following language:

“I certify, based on information and belief formed after reasonable inquiry, the statements and information in the document are true, accurate, and complete.”


Hardcopy Submittal. The Turn Around Document contains a cover sheet with general facility information, followed by one or more pages for each emission unit, and finally a plant summary page used for certification that must be signed by a “Responsible Official”. Use blank forms for any changes or additions to the pre-printed inventory. In general, one Point Page will usually be needed for each emission unit and additional Pollutant Pages if there are emissions of more than two pollutants. Visit the Emissions Inventory part of the DEQ website at for more information plus help with completing Turn Around Documents and submitting emissions inventories. There, you will find other reference tables and copies of blank Turn Around Document forms on our “Turn Around Documents: Instructions and Help” page.  There is also a “Frequently Asked Questions” (FAQs) page on the site.



2. Company Information

Company Name:  The name of the legal entity or company currently owns or operates the facility.


Facility Name:  A unique facility name, facility location, or facility designation. The facility is the location where activities resulting in air emissions occur or have occurred.


Company Mailing Address:  The business address to which mail is delivered, which can be distinct from the company's physical address.



3. Facility Information

Facility Physical Address:  The physical address of the facility. A PO Box or Rural Delivery Route Number is unacceptable.


Facility Status:  The operational status of the facility (selections listed below). A facility can change their status, but by doing so are certifying the accuracy of the updated status. Permit exempt or de minimis facilities are not required by OAC 252: 100-7-1.1 to submit annual emissions inventories.  If a facility should be updated to permit exempt or de minimis in our records, please notify our office in writing (email, fax, or letter).


Active–select this status if the facility operated at any time during the year.


Idle–select this status if the facility was idle or did not operate for the entire year. All emission units must have a status of Idle if this facility status is selected.


Closed–select this status only if the facility has been permanently shut down and will no longer operate. Please note that if the facility operated at any time during the relevant emissions inventory reporting (calendar) year, its status may not be changed to “Closed” until the following year.


Not yet builtselect this status only if the facility was under construction and did not begin operating within the year. 



NAICS: North American Industry Classification System. Enter the primary NAICS for overall facility operations. See for valid NAICS values and conversion tables from NAICS to SIC and from SIC to NAICS.


SIC:  The Standard Industrial Classification code for the facility. This can be determined at


TRI: The unique ID that is assigned to the plant in the EPA Toxic Release Inventory (TRI) data system. Provide if reporting any HAP emissions.


ORIS: Office of the Regulatory Information System. This is a unique identifier for electric generating units (primarily SIC = 4911). An ORIS Code is assigned by the US Department Of Energy, Energy Information Administration (EIA) and is reported by industry on DOE EIA Forms. See


Issued Permits: Starting with the most current permit, list the active permits issued for this facility. For new facilities, list the permit number and the date it was issued.


Comments to and from DEQ about this Facility: Use this memo field to explain entries or to address other issues in the document where more information might be necessary. Also, please review any notes from DEQ.


Inventory Format for Next Year:
      •  Redbud - to submit inventories electronically using the Redbud web application
      •  Hardcopy - to receive inventory forms by mail
      •  Snapshot - to receive inventory forms as Adobe® PDF files via email


Responsible Official: Name, phone, fax, and email address of the individual responsible for the facility. A “Responsible Official” is defined in OAC 252:100-1-3.



3.1 Facility Location

County: This box should contain the county where the facility is located.


Legal Description:  The sub-section, section, township, and range of the facility.


Geographic Coordinates: Please provide the Latitude and Longitude for the main gate or entrance to your facility. It is not necessary to provide both types of coordinates. If pre-populated information is present on your form or in Redbud then it should be updated ONLY if you have valid GPS (Global Positioning System) data.


Note: All geographic coordinates must be provided for the same datum, specifically NAD (North American Datum) 83, which is the same as WGS (World Geodetic System) 84. This reference system is predominantly used today, such as for GPS data. However, some USGS topo maps are based on the earlier NAD 27. In that case, the coordinates must be converted to NAD 83 coordinates, which can vary by a kilometer or more.

Latitude – State in decimal degrees, not in degrees, minutes, seconds.

Longitude – Must be a negative number (to indicate west of the Greenwich Meridian). State in decimal degrees, not in degrees, minutes, seconds.


4. Emission Unit Information

Sequence Number:  A number for the particular emission unit assigned by the Air Quality Division that facilitates easy reference within the sequence of emission units at a facility. For new emission units when reporting via hardcopy, use the next available sequence number. In Redbud the Sequence Number will increment automatically when a new emission unit is added.


Emission Unit Name:  The current name of the emission unit. Every emission unit must have an emission release point, at least one process and if active, one or more pollutants, which may also include control equipment information.


Notes to or from DEQ about this unit:  Use this area to address issues relating to this emission unit and its associated emission release points, processes and emissions, such as an explanation for a change in emissions or a like-kind replacement.


Emission Unit Type:  A description that uniquely identifies the emission unit chosen from the Unit Type table. Examples include but are not limited to, boilers, engines, tanks, spray booths, fugitive sources, and crushers.


Emission Unit Status:  The operational status of the emission unit. The possible selections are:


Operating–this emission unit operated all or part of the calendar year (Active at any time during the year).


Temporarily Shutdown–this emission unit did not operate at all during the calendar year, but may restart at some time in the future (no emissions during the calendar year; Idle for the entire year).


Permanently Shutdown–select this status if an emission unit has been removed, removed from service, or is permanently shutdown (no emissions during the calendar year).


Location of the Emission Unit:  Only alter existing information with valid GPS data.

Latitude – State in decimal degrees, not in degrees, minutes, seconds.

Longitude – Must be a negative number (to indicate west of the Greenwich Meridian). State in decimal degrees, not in degrees, minutes, seconds.


5. Emission Release Point INFORMATION

Stack/Emission Release Point Name:  Describes the point or area at which emissions are released into the environment, via a stack or fugitive release. A release point can define the area over which fugitive emissions occur.


Stack/Emission Release Point Type: Selections are: Fugitive, Vertical, Horizontal, Goose Neck, Vertical with Rain Cap, Downward-Facing Vent


Stack/Emission Release Point Status: The operational status of the stack/emission release point. The possible selections are:


Operating–this stack/emission release point operated all or part of the calendar year.


Temporarily Shutdown–this stack/emission release point did not operate at all during the calendar year, but may restart at sometime in the future.


Permanently Shutdown–select this status if a stack/emission release point has been removed, removed from service, or is permanently shutdown.



5.1 STACK PARAMETERS  (Do not apply to Fugitive Emission Release Points)


Stack Height:  Height above grade of the stack in feet.


Stack Diameter:  Diameter of the stack in feet. For non-round stacks, the diameter equals the square root of the length times width multiplied by 1.128 as stated in the following equation:

Non-round Stack Diameter Formula


Gas Exit Temperature: The temperature of the exit gas stream in degrees Fahrenheit.


Flow Rate: Numeric value of stack gas flow rate in actual cubic feet per minute (acfm).


Gas Exit Velocity:  The exit velocity of the exhaust stream in feet per second (fps). To convert the Flow Rate to Gas Exit Velocity divide the flow rate (acfm) by π r 2 (where r = 0.5 x Diameter) and by 60 seconds/minute as shown in the following equation:


Gas exit velocity (fps) = flowrate (acfm) ÷ (π × r 2 × 60)



5.2 FUGITIVE RELEASE PARAMETERS  (Do not apply to Stacks)


Fugitive Height:  Height above grade in feet of emission release point for emissions not routed through a stack (tanks, fugitives, stock piles, etc.). Where there is no identifiable stack, provide the height in feet above ground at which the emissions enter the atmosphere. This may also be appropriate for stacks with a minimal flow rate (e.g., still vents, lab hoods). If stack dimensions are reported the Fugitive Height is zero (0).


Horizontal Area of Fugitive Emissions: Area over which fugitive emissions are released, in square feet. In the case of a storage tank, this would be the area of the tank vent, or surface area of a stockpile. However, for facility-wide fugitives at a large plant, this would be the area of the entire facility. If stack dimensions are reported the Horizontal Area of Fugitive Emissions is zero (0).




SCC: The EPA Source Classification Code for the process. The SCC describes an emissions process or activity. At general instruction SCC table you will find a table with all SCCs (in Microsoft Excel format). A smaller table, "SCC 3-Digit Primary Point Source Categories," found at general instruction SCC 3-Digit table, lists the major industry groups. It is important to stay within a specific industry group. For more information about SCCs, see the EPA’s Chief website (, in particular the AP-42 emission factors documentation and the FIRE program.


Emission Process: Description of each process or activity at a particular emission unit (this description is assigned by the SCC). A single emission unit may have two or more processes (and so SCCs) if more than one material is used. For example, a single boiler will have two SCC's is it burns both fuel oil and natural gas.


Material: The substance from which the pollutants were created by each process. Depending on the type of source category, material may refer to the type of fuel combusted, raw material processed, product manufactured, or material handled or processed. A table of the material descriptions to be used can be found at: general instruction materials table.


Material Input/Output: Indicate whether the material defined above was:

  • consumed (used),
  • produced, or
  • existed.


Process Rates:  Hourly, Daily, and Annual process or activity rate, measured by the process rate units which are typically defined by the process SCC.


The rate is a measurable factor or parameter that relates directly or indirectly to the emissions of an air pollution source. Note that this is the rate of the process that produces emissions, and is not necessarily the amount of throughput of material passed through a piece of equipment. For example, for a compressor engine that is burning natural gas, the process rate would refer to the amount of natural gas burned by the engine, not the amount of gas compressed by the engine-driven compressor.


Depending on the type of source category, activity information may refer to the amount of fuel combusted, raw material processed, product manufactured, or material handled or processed. It may also refer to population, employment, number of units, or miles traveled. Activity information is typically the value that is multiplied by an emission factor to generate an emissions amount that should be expressed as tons per year (tpy).


  Hourly Maximum hourly rate at which the process unit can operate. This figure is used in modeling studies.
  Daily A rate that characterizes how, on a representative day, a particular process unit operated during the reporting year.
  Annual Actual annual process rate.


Process Rate Units: The units of measure used to quantify the rate of the activity that produces air emissions (these are typically assigned by the SCC).



6.1 DESIGN RATINGS AND FUEL COMBUSTION DATA  (Applies to certain processes only)


Design Capacity:  Report only if unit is a boiler, turbine or an internal combustion engine. Design Capacity of the process equipment operating at 100% of the designated rate. For a boiler, Design Capacity is based on the reported maximum continuous steam flow. Report the value for the design capacity for a boiler as MMBTU/Hr (Million British Thermal Units per Hour). For a turbine report the design capacity as Horsepower (hp) or Megawatts (MW). For an internal combustion engine report the design capacity as Horsepower (hp).


Fuel Heat Content:  The heat content of a fuel in Million British Thermal Units per the standard unit of measure for that type of fuel, that is:

  1. MMBTU per Million Standard Cubic Feet (gaseous fuels)

  2. MMBTU per Ton (solid fuels)

  3. MMBTU per 1000 Gallons of oil (liquid fuels)


Sulfur %:   Percent Sulfur, by weight, in the process fuel. The value must be between 0.01% and 10%, inclusive.


Ash %:       Percent Ash, by weight, in the process fuel. The value must be between 0.01% and 20%, inclusive.




Hours per Day must be a number between 0 and 24 (inclusive). Typical hours per day that the emitting process operates during the inventory period.


Days per Week must be a number between 0 and 7 (inclusive). Typical days per week that the emitting process operates during the inventory period.


Weeks per Year must be a number between 0 and 52 (inclusive). Typical weeks per year that the emitting process operates during the inventory period.


Actual Hours per Year represents the total actual hours the process operated during the calendar year for which the emissions inventory is being submitted. For leap years, Actual Hours per Year must be a number between 0 and 8784 (inclusive). For all other years, this must be a number between 0 and 8760 (inclusive).


Seasonal Operating Fractions:  The fraction of the total operation that occurs in each season. Report these in decimals (25% should be reported .25). This expresses the part of the actual annual activity information based on the four seasons (e.g., production in summer is 40%, i.e., 0.40 of the year’s production). The total Seasonal Operation shall equal 1.00, i.e., 100%.

Spring — The percentage of the total annual activity that a process operates during the Spring months (March, April, May).

Summer —The percentage of the total annual activity that a process operates during the Summer months (June, July, August).

Fall —The percentage of the total annual activity that a process operates during the Fall months (September, October, November).

Winter —The percentage of the total annual activity that a process operates during the Winter months (December, January, February, all from the same reporting year, i.e., Winter 2015 = January 2015 + February 2015 + December 2015).



Pollutant:  Name of the substance, compound or compound group of which emissions are produced.


CAS:  Chemical Abstract Services registration number for the pollutant.


Method of Calculation: The Approved Method used for computing or measuring emissions.


Emission Factor: The ratio relating emissions of a specific pollutant to an activity or material process rate. The numeric value of this field is dependent upon the calculation method and the emission factor numerator and denominator units. A pollutant-specific emission factor is typically expressed as pounds per process rate units. Uncontrolled emission factors should be reported here. Where applicable, reduce the resulting amount of emissions by the actual capture and control efficiencies of the control scenario.


Numerator Units: Usually pounds but can be another unit, such as grams where the emission factor is grams per horsepower-hour (g/Hp-Hr).


Denominator Units: These units are usually the same as the process rate units. For example, for a natural gas boiler the process rate is measured in million standard cubic feet; the emission factor unit numerator would be pounds and the denominator would be million standard cubic feet (lbs/mmscf).

Note:  For calculation methods where there may not be one single emission factor used to compute the actual emissions (e.g., Tanks, GRI-GlyCalc 4, CEMS), enter zero (0) in the emission factor field and for the numerator and denominator units select:.

* N/A - Formula, Software or CEMS

Trace (<0.001 TPY)):  Use the Trace check box to indicate annual emissions have been calculated but are less than 0.001 Tons (2.0 lbs).


Actual Emissions (Tons):  Amount of actual annual emissions of the pollutant, after application of air pollution control equipment, reported in tons per year. The actual emissions for a plant, emission unit, or process—measured or calculated—that represents a calendar year. This total shall include emissions from fugitives, upsets, startups, shutdowns, malfunctions, and excess emissions.


Reference:  The specific source or material containing the method of calculation and factor. For AP42, use the Table number, e.g., Table 1.4-1. For Permit Factor, insert the permit number. Fire will list the AP42 section, table or EPA document. Other References may be EPRI, RMA, or UEF, etc. The following may or may not have a Reference: Cont. Emissions Monit. Data (CEMS) , DEQ Approved Method, EPA Reference Method Stack Test, Fuel Usage Data , GRI-GLYCalc , Manuf. Test Data (w/ DEQ approval), Mass Balance, Similar Unit EPA Reference Method Test, TANKS, and Vasquez-Beggs.


Method/Factor Includes Control Efficiency:  Check this box if the emission factor includes the control efficiency.


Excess Emissions (Tons):  Any "Excess Emissions" as defined by OAC 252:100-1-3, Definitions. This amount shall be included in the Total Amount of actual emissions.


Permit/Rule Limit (Tons/Year):  The total amount of any regulated air pollutant which is subject to an emissions limiting standard, either by rule or permit condition contained in an enforceable permit or potential to emit, or for grandfathered sources, emission limits based on maximum design capacity and considering all applicable rules.


Capture Efficiency:  The percentage of air emission that is directed to the control equipment, or an estimate of that portion of an affected emissions stream that is collected and routed to the control measures, when the capture or collection system is operating as designed.


Control Scenario (Primary and Secondary):  Control system, abatement equipment or approach applied to reduce emissions of the pollutant.


Control Efficiency (Primary and Secondary): The amount of actual air emissions prevented from being emitted by the control scenario. The actual efficiency should reflect control equipment downtime and maintenance degradation. Report as a percentage.




Tables covering SIC, NAICS, SCC, Material, Material I/O, MACT, MACT Status and Approved Methods of Calculation, are found on the DEQ website at: general instruction tables.