Emission Inventory System (EIS)


An emissions inventory is a compilation of data describing emissions from different sources of air pollution. The source may be a utility, refinery, automobile, train, wildfire or road construction. Each type of source can be placed into a point, area or mobile source category.

Purpose of an Inventory

An inventory is the foundation of a regulatory program. Having a complete inventory, Ohio EPA's Division of Air Pollution Control (DAPC) can answer questions such as ‘What is the current status of pollution in Ohio?’, ‘Which facilities are the largest emitters of pollution?’, ‘What types of emissions are currently controlled’ and ‘How well are they controlled?’

Based on the answers to these questions, DAPC can control sources of pollution through responsible regulation. An inventory will test the rule's effectiveness and extrapolate emissions into the future. There are many other purposes and uses of an emissions inventory, but in general it is the primary tool to identify where the State currently stands in terms of air pollution and what needs to be done in the future to reduce emissions. An inventory serves as a starting point, or a baseline, which allows Ohio to develop goals and the best ways to meet them.

Point Sources

A point source is a stationary source that can best be described as a manufacturing plant or a similar entity having one or more units discharging air emissions into the atmosphere and located at one specific geographic area.

Area Sources

Area sources are typically small, individual, numerous, and have not been inventoried as specific point, mobile, or biogenic sources. For inventory purposes, they are grouped with other like sources into categories that allow emissions to be calculated collectively using a specific methodology that is designed to estimate emissions at the county level. 

Ohio EPA uses published Emission Inventory Improvement Program (EIIP) methodologies or selects other methodologies used by other states. The decision of which methodology to use is largely based on Ohio’s data availability. Data which is not available on a county-level is estimated by assigning a percentage of the state’s total activity to each county based on the state’s population or employment information.  

The area sources presented below are those that emit oxides of nitrogen (NOX) and/or VOC into Ohio’s atmosphere.

Categories included in the 2005 area source inventory 

VOC Emissions

NOX & VOC Emissions

NOX Emissions

Agricultural Chemical Applications

Outdoor Wood Boilers

Human Cremation

Architectural Surface Coatings

Industrial Distillate Oil Combustion


Auto Body Refinishing

Industrial Residual Oil Combustion 


Consumer & Commercial Solvents  

Industrial Natural Gas Combustion


Solvent Cleaning

Residential Coal Combustion          


Fuel Marketing

Residential Distillate oil Combustion 


Graphic Arts

Residential LPG Combustion  


Hospital Sterilizers

Residential Natural Gas Combustion


Industrial Rubber & Plastics

Residential Wood Combustion


Industrial Surface Coating

Structure Fires


Municipal Solid Waste



Portable Fuel Containers






Traffic Markings




Mobile Sources


Generally speaking, U.S. EPA classifies anthropogenic (manmade) emissions into three broad categories, mobile, stationary (point), and area sources. Mobile source emissions are further disaggregated into on-road (e.g., cars, trucks, and motorcycles) and non-road emission categories. 

Because of the significant contribution of non-road emission sources to the total mobile source emission inventory, it has become critical over the past several years for the EPA to provide state and local pollution control agencies with the ability to easily create and project accurate, reproducible inventories of non-road emissions. 

Categories of Mobile Source Emissions

There are three categories of mobile source emissions: 

  • Exhaust or tailpipe emissions, which result from the combustion of fuel in the sources engine
  • Evaporative emissions, which result from evaporation of fuel from the engine or its fuel system
  • Refueling emissions 

Exhaust Emissions: Are the result of fuel combustion and occur only when the engine is running. 

Evaporative Emissions: These are VOC based only and are continuously emitted from an engines fuel system, whether the engine is running or not. Gasoline is a very volatile fuel, so total VOC emissions from gasoline powered vehicles have a large evaporative component. Diesel and jet fuels are of very low volatility, so evaporative emissions from diesel and turbine engines are a much smaller part of their total VOC emissions. Evaporative emissions for CNG or LPG powered vehicles are negligible because their fuel tanks and systems are, of necessity, sealed.   

Evaporative and exhaust VOC emissions can be calculated separately for most mobile source categories, but in this inventory these two components are combined into total VOC. Evaporative emissions do not include VOC emissions that occur during refueling. 

Refueling Emissions: These emissions are entirely VOC. Although they result from the evaporation of fuel, they are distinct from, and not directly related to, evaporative emissions as defined above.   

Refueling emissions have two subcomponents: 

  • Displacement Emissions: These occur when new fuel is transferred into a partly filled tank - be it a service station storage tank, a portable fuel container (gas can), or a vehicle or engine’s fuel tank -displacing the air in the tank and forcing that vapor-rich air out the inlet pipe or other vent. There are two stages of displacement emissions: 
    • Stage I emissions occur when the underground storage tanks at a service station are being refilled.

    • Stage II emissions occur when a motor vehicle (or gas can) is being refueled. 

  • Spill Emissions: These occur when drops of fuel drip or splash on the ground during or after refueling and evaporate away. 

Mobile source emissions are further disaggregated into two categories:

EIS Submittal Reports

Ohio EPA has the authority to under Ohio Administrative Code (OAC) rule 3745-15-03 to request and receive the information from regulated entities. Emissions information is provided to U.S. EPA to develop an annual criteria and toxic pollutant inventory pursuant to 40CFR 51.321. Beginning with the calendar year 2006 inventory, all Title V facilities are required to file a complete an inventory. Pollutants required to be reported in the EIS are: NOx, VOC, SO2, Lead, OC, CO, NH3, PM-CON, PM-FIL, PM10-FIL and PM2.5-FIL

What's New

  • All EIS reports must be submitted no later than close of business on April 15 of each reporting year. (see Q&A #1)
  • Air Services (launched June 30, 2008) is the only method available to submit EIS reports (see Q&A #2)
  • Steps to take now to meet your EIS reporting deadline (see Q&A #8) 
    • e-Business Center: Air Services -  it will take five business days to obtain your PIN (see Q&A #2)
    • Facility Profile - Review your data and correct any inaccuracies (see Q&A #6)
    • Complete and submit your emissions report  (see Q&A #7)

What’s New - Questions and Answers

1. What is the new deadline to report EIS?

All TV facilities must report EIS data no later than April 15 by close of business. All reports are to be sumitted using Air Services software which is a web based software developed by the Ohio EPA, Division of Air Pollution Control (DAPC), to assist facilities in preparing and submitting a variety of electronic permit applications and reports to DAPC.

2. Will I have to install the Air Services software?

No. The user will not have to install this new software. However, you will have to gain access and software privileges in order to submit reports. To gain access and privileges, you will need to go to the e-Business Center and create an account. Once created, you must fill out a PIN request form, submit it through a simple online interface and download the hard-copy form. This form must be notarized to verify your identity and returned to the Ohio EPA before you can gain access to facility data as a Responsible Official.

Once granted a PIN, you will then need to request, via the e-Business Center, access to your specific facility(s) data. To protect potentially sensitive data, the Responsible Official will need to fill out a second online form indicating the facility you want to access, sign the form via the PIN and submit to the EPA for approval. Once granted, as the Responsible Official you will now be able to delegate your privileges to other users, such as consultants or your staff. Delegating your privileges will enable others to work on the emissions reports for the facility(s) you choose to delegate. More detailed information may be obtained through the e-Business Center: Air Services.

3. Will the existing data in STARShip be migrated to the new software?

Yes. Data for your facility records in the Air Services will be populated from existing STARShip files that were submitted to us in the past, in addition to other databases we have with information relating to PTI’s, old Permit(s)-to-Operate, Permit-By-Rule, etc. Therefore, you will need to review the information that migrated and clean up that data by building correct relationships between equipment as it is used at the facility. This must be done before emissions reports are submitted.

4. How do I clean up my migrated data?

To start you must complete the Air Facility Profile in order to submit an emissions report via Air Services. Once you complete the Air Facility Profile, most of the data input for the emissions reports is done. Air Services is designed to ensure that the critical information is kept in the Air Facility Profile. Therefore, the Source Classification Code (SCC) that describes the processes of the emissions unit(s) is kept there. In addition, data that is needed to calculate emissions and control equipment efficiencies is kept at this level. The bulk of the remaining emissions report data pertains to actual throughput data. The Air Services is equipped with a more accurate emissions calculator with up-to-date emissions factors to assist you in calculating emissions (see question #6 below).

5. What do I do if I have to revise my EIS report which I submitted through STARShip and STARShip is no longer available?

If you submitted your EIS report using STARShip and that report is found to be un-approvable upon Ohio EPA review or you decide that it needs to be revised after June 13, 2008, you will be required to submit any revision(s) using Air Services. This is because the report you submitted earlier in the year (which was migrated to the new software), will lack the additional data required by Air Services and the revisions will fail to meet the Air Facility Profile requirements and data quality assurance. Learn more in question #2 about what you have to do to use Air Services.

6. How do I revise my Facility Profile?

Each profile page should be reviewed to verify that the current data is correct. If any data is incorrect, you will need to edit the profile information page by selecting profile change from the Air Services Home, ‘In Progress Tasks.' Other data which may need to be edited while you are in the Facility Profile are the emissions units (EU), processes, any associated control equipment, and any egress points, if applicable. Each point along the facility tree on the right side of the screen can be clicked and edited. If you have a shut down EU, you will need to enter a shut down date through the edit mode.

Any EU labeled as a temp will need to be edited to be associated with the proper control equipment and egress points. Any disassociated control equipment or egress points may be deleted if they do not belong to any EU. All EU’s, which exist on your facility tree, must have a process. Each process must have an appropriate Source Classification Code (SCC) which can be obtained from the drop down box in the process information page by clicking on the SCC cascading levels button or the SCC search by keyword button.

If you need to create control equipment or egress points, click on the Facility ID next to the top icon and enter all the requested information. If this data is already available due to migration, please review it to make sure it is accurate. It is critical that each facility be completed correctly and completely to avoid errors in the emissions report. Once you are done editing your profile, click the validation button and correct any errors until you obtain a successful validation.

7. How do I complete and submit my Emissions Report?

Once your Facility Profile has been successfully validated, you can start working on your emissions report by clicking on the report through the In-progress Task at the Air Services Home. Click on the process and begin to complete the required information by clicking on the edit button. When completing the pollutant table, do not leave any criteria pollutant blank or pending, if you do not emit a certain criteria pollutant, select the emissions best engineering judgement and enter 0. When your report is complete, click the ‘validate’ button and correct all errors until you achieve successful validation. A submit button will pop up and you are ready to submit your report.

8. Is Air Services vastly different from STARShip?

Yes. Although the existing data will be migrated into Air Services, Air Services is designed to collect more information than STARShip, therefore, it will contain more data.The mechanisms utilized by Air Services to enter and accept the data is different and the new system offers more options to the user.

This new application is web based which will eliminate a lot of the time previously required to quality assure and revise the reports because Air Services will prompt the user to revise incorrect or incomplete entries in live time. The user has the ability to correct errors before submitting any reports to the Division of Air Pollution Control (DAPC).

As with any new system, the user must practice using it and get familiar with its components. DAPC strongly urges all Air Services users to practice using it and NOT wait until you need to submit your report to learn how to use it. Waiting to learn Air Services until you need to use it may present you with difficulties that you may not have sufficient time to address.

9. What authority does Ohio EPA have to collect the EIS data?

Pursuant to Ohio Administrative Code (OAC) 3745-15-03, The Director of the Ohio EPA has authority to request and receive the information from regulated entities. Additionally, it is the State’s obligation to submit emissions inventory files to U.S. EPA pursuant to 40CFR 51.321.

10. Is there any way of getting out of submitting an EIS report?

Yes. There are three ways to avoid submitting an EIS report:
  • The facility emitted all EIS pollutants in amounts less than 1 ton per reporting year.
  • The TV emissions units did not operate at any time during the reporting year.
  • The TV emissions units which operated during the reporting year, emitted non-EIS pollutants only.

EIS Pollutants are: NOx, VOC, SO2, Lead, OC, CO, NH3, PM-CON, PM-FIL, PM10-FIL and PM25-FIL

Ohio Emissions Inventory point source data is now available to download.


EIS Data


EIS90.ZIP  - model90.dbf (FoxPro 2.6) and key90.doc (definitions - MS Word 7)


EIS95.ZIP  - model95.dbf (FoxPro 2.6) and key95.doc (definitions - MS Word 7)


EIS99.ZIP - model99.dbf (FoxPro 2.6) and key99.doc (definitions - MS Word 7)


EIS2000.ZIP - EIS2000.XLS (Excel spreadsheet) - facility, emission unit, emissions, process, control, stack, and permit data for 2000 emissions.


EIS2001.ZIP - EIS2001.XLS (Excel spreadsheet) - facility, emission unit, emissions, process, control, stack, and permit data for 2001 emissions.


EIS2002.ZIP - EIS2002.XLS (Excel spreadsheet) - facility, emission unit, emissions, process, control, stack, and permit data for 2002 emissions.


EIS2005.ZIP - EIS2005.XLS (Excel spreadsheet) - facility, emission unit, emissions, process, control, stack, and permit data for 2005 emissions.


EIS2008.ZIP - EIS2008.XLS (Excel spreadsheet) - facility, emission unit, emissions, process data for 2008 emissions.


EIS2009.ZIP - EIS2009.XLS (Excel spreadsheet) - facility, emission unit, emissions, process data for 2009 emissions.


EIS2010.ZIP - EIS2010.XLS (Excel spreadsheet) - facility, emission unit, emissions, process data for 2010 emissions.


EIS2011.ZIP - EIS2011.XLS (Excel spreadsheet) - facility, emission unit, emissions, process data for 2011 emissions. 


EIS2012.ZIP - EIS2012.XLS (Excel spreadsheet) - facility, emission unit, emissions, process data for 2012 emissions


EIS2013.ZIP - EIS2013.XLS (Excel spreadsheet) - facility, emission unit, emissions, process data for 2013 emissions
2014  EIS2014.ZIP - EIS2014.XLSX (Excel spreadsheet) - facility, emission unit, emissions, process data for 2014 emissions

Coal Burning Reports  

Please see the common questions and answers below or Visit the Agency's Answer Place to post your questions or find answers.


Which pollutants are included in the inventory list?

The Air Services pollutants reference table accounts for 629 pollutants: 11 criteria air pollutants (CAP); 150 hazardous air particulate pollutants (PM-HAP);131 hazardous volatile organic pollutants (VOC-HAP), 217 hazardous air pollutants (HAP) and 120 miscellaneous non-reportable pollutants. 

How is the list of pollutants compiled?

The list is compiled from pollutants that appear in the National Emission Inventory (NEI) pollutant reference table, Ohio EPA’s old permitting and reporting application (STARS) and Section 114 Right to Know program. The NEI Pollutant List can be viewed by clicking here and by downloading the "EIS Code Tables (including Source Classification Codes [SCCs]) (MDB 6M)" Access database.

Why is there such a large list of default HAPs associated with my process?

The Air Services generic list of hazardous air pollutants (HAPs) associated with your process consists of Web FIRE and State pollutant records. There is an extensive list of pollutants for fuel burning processes. For some processes, such as wood burning boilers, it is not unusual to encounter 50 to 60 HAP. 

Why are there no HAPs associated with my process?

While the Air Services generic list of hazardous air pollutants (HAPs) consists of an extensive Web FIRE and State pollutant records, some processes do not have Web FIRE or State generic pollutants. For those processes, Ohio EPA relies on the facilities to report their HAP emissions. If you are aware of a HAP that is emitted from your process, but it is missing in your generic pollutant profile, you are advised to create a pollutant entry in the table.  

Why do all 11 of the CAPs appear for every process?

The 11 criteria air pollutants (CAPs) are critical to the Division of Air Pollution Control (DAPC) for fee calculation, compliance demonstration and inventory purposes. All 11 CAPs appear every time you report a new process to ensure that all 11 pollutants are properly considered prior to certifying the accuracy and completeness of your report.  

Can I modify the pollutants list that appears on the inventory report?

The list of pollutants appearing in your inventory report which consists of the 11 criteria air pollutants (CAPs) cannot be modified. The hazardous air pollutants (HAPs) from the Air Services pollutant profile related to your process can be modified and customized to include only what your process emits to ensure a complete and accurate account of your HAPs.

Should I compare the Air Services pollutant list with the TRI toxics inventory, MACT database and acid rain report?

Yes. Facilities are advised to compare and cross check pollutant lists to ensure consistency among reporting requirements. This will also aid in improving the quality of the data being reported to the TRI, MACT and acid rain programs.

Emissions Factors

How is the list of Air Services emissions factors compiled?

The emissions factor list originates from Web FIRE and is processed in-house using a Microsoft Access application and exported into Air Services. Only uncontrolled and un-revoked Web FIRE records are considered in the original compilation of emissions factors. The factors are processed to achieve consistency with reporting units, measures and material codes within each Source Classification Code (SCC). Since there are significant emissions factors gaps in Web FIRE, Ohio EPA intends to identify and fill those gaps in the future using all available resources. The Air Services emissions factors table is a dynamic list and it will be updated once a year with the most up to date factors.

Which emissions factors are used in the calculation of HAPs?

The Air Services table of emissions factors is used in the calculation of your process of hazardous air pollutant (HAP) emissions. The internal calculator is designed to use the generic Air Services table of emissions factors to assist you with the calculation of emissions. Although the generic emissions factors are pre-selected for HAP calculations, the user can select other calculation methods and enter emissions factors which are specific to the operation.

Can I replace the default emissions factor with a better factor or emissions estimate?

Yes. Although the default emissions factors serve an important inventory and reporting purpose, they should only be used when no other factor is available because each default factor is associated with a high degree of uncertainty. Many of those emissions factors are generated based on a limited number of tests and the numeric value of the emissions factor may be off by a significant margin. If there is a source specific data available, the Division of Air Pollution Control (DAPC) encourages the use of that specific factor or emissions calculation. Example situations where the default factor should not be used are: process specific test, stack test, material balance, engineering studies, or emissions factors from an association.

Do I need to ensure that the stack test or process specific derived emission factor is used in the calculation of emissions?

Yes. It is far preferable to use results from the facility's own stack testing or process derived emissions factors than the default emissions factor. Facilities subject to testing are expected to use the test results in the calculation of emissions. Specific test results offer the most accurate information regarding the facility’s emissions and therefore, the calculations will be more correct than from other sources.

Are there any controlled default emissions factors in Air Services?

No. The Air Services list of emissions factors consists only of uncontrolled emissions factors. This has been a Air Services design decision. The calculation of uncontrolled emissions is needed to account for the fugitive and stack emissions.


Why is there a limitation on material and throughput information?

There is a dual purpose for this limitation, standardization and consistency.

First, standardization is needed to achieve pollutant calculation efficiency.In order to standardize material and throughput information with emissions factors, each Source Classification Code (SCC) is analyzed and the material and throughput information is limited to one (or in some rare cases many) combination. The default emissions factors are also converted to the same set of material and throughput combination. Those conversions are necessary to automate and calculate emissions for all pollutants that are based on the default emissions factors. The benefit is evident for processes with many pollutants. For example, for fuel burning processes, there are as many as 50 to 60 pollutants per process. Air Services is designed to calculate emissions for all those pollutants in the easiest manner possible without the facility involvement for every pollutant record.

Second, this limitation is needed to achieve reporting consistency among facilities and processes. This is especially crucial since the material and throughput information is used for more than just calculating emissions. The data is used by rule writers, policy makers, and environmental professionals to satisfy reporting requirements related to throughput usage (i.e., how much coal is burned in Ohio), compile Area Sources Inventories, develop State strategies, and produce greenhouse gas inventories.

My process is not described in the Air Services SCC list. What do I do?

U.S. EPA’s list of Source Classification Codes (SCCs) is designed to capture the majority of the industrial processes. The list undergoes continuous refinements. U.S. EPA occasionally revokes certain SCCs and provides replacements or simply adds new ones. Thus, prior to each reporting year, Ohio EPA will update the Air Services list to conform with U.S. EPA’s list. If your process SCC is revoked, you will be asked to select another from the valid list of SCCs. In the event that your process truly lacks a proper SCC, the facility must contact the Division of Air Pollution Control (DAPC) in advance of the reporting deadline to obtain a specifically created Ohio SCC for that process. Ohio EPA may petition to U.S. EPA for a new SCC. Should U.S. EPA develop an appropriate SCC for that process in the future, the facility can start using that SCC in place of the DAPC created one.

My process material and throughput information are not matching the Air Services defaults. What do I do?

Each Source Classification Code (SCC) is assigned one or more default combination of material and throughput information. If your process is not matching the Air Services defaults, you have two options: convert your process information into standard Air Services defaults; or request an Ohio SCC.

If your process derived emissions factor is not compatible with the process defaults, you can describe the calculations in a spreadsheet and submit them through Air Services.

What does it mean when a ‘select’ button appears in the 'material information, annual average operating schedule and throughput percent' box?

The 'select' button will appear when the ‘edit’ tool is used to revise the information in the 'material information, annual average operating schedule and throughput percent' box. If the Source Classification Code (SCC) used for this process has more than one material defined, then the select column is used to specify which material is the correct one.

What does it mean when in the 'process emissions' table, under column uncontrolled emissions factor, and sub‑column 'factor (lbs/X)' it states 'pending FIRE row'?

When 'Ohio EPA Emission Factor' is selected and the factor column specifies 'pending FIRE row,' it means that Air Services does not know what factor from FIRE to use. Either for the Material/Action/Material Units that has been specified, there is more than one FIRE entry for that pollutant or there are none.

What do I do when I click to edit and the factor is not edited?

If the calculation method ('Ohio EPA Emission Factor') is clicked, a window will pop up to show the FIRE choices. If there is more than one choice, then a selection can be made by the user. If only one choice is available, then Air Services automatically selects that option. If no choices are available, then 'Ohio EPA Emission Factor' cannot be selected.

How should I report emissions for a process with multiple material throughputs or processes with complex emissions calculations?

The emissions reports in STARS2 facilitate the reporting of emissions for criteria, fee and hazardous air pollutants (HAPs). STARS2 is designed to capture emissions using two different methods: Emissions Factor method or Emissions method.

The Emissions Factors method is the most efficient method for a process with a single throughput and one emissions factor in the calculation of emissions. Please note that throughput is the term that describes the material being processed and the amount of material in units of mass or volume.The emissions factor describes the amount of pollution in pounds released to the atmosphere per unit for throughput.The majority of the processes are expected to use the Emissions Factors method in the calculation of emissions.

The Emissions method is the alternative methodology and it is designed for processes with multiple materials and complex emissions calculations. For example, paint and coating operations use multiple material throughputs within a reporting year and do not fit well with the simple calculation method of the Emissions Factor method. For those cases, the facility is requested to select the Emissions method and perform the following steps:

  • Identify HAPs from material safety data sheets
  • Report the one material that is most frequently used and best describes the process in the 'Material' column
  • Report the throughput value that summarizes the total amount of mass or volume from all processed material in the 'Throughput' column
  • Select one of the available Emissions methods and manually enter the emissions for each pollutant; ensure allocation of reported emissions to the correct stack and fugitive column
  • Since the emissions calculations are performed outside of STARS2, it is recommended that the calculations are provided and attached in a file format that is acceptable to STARS2. The attached file will assist the State reviewers with the review of the report and answer any questions related to the calculated emissions.

Emissions Units

Which emissions units do not need to be reported in the EIS report?

Emissions units that meet any of the following conditions are exempt from reporting EIS:
  • Title V insignificant emissions units with less than 1 ton per year of each of the  pollutants listed below
  • Title V non-insignificant emissions units that emitted less than 1 ton per year of each of the pollutants listed below
  • Title V emissions units that did not operate at any time during the reporting year
  • Title V emissions units that emitted 1 ton or more per year (see Engineering Guide 71) for pollutants other than those listed below
    • Nitrogen oxides (NOx)
    • Volatile organic compounds (VOC)
    • Sulfur dioxide (SO2)
    • Lead (Pb)
    • Organic compounds (OC)
    • Carbon monoxide (CO)
    • Ammonia (NH3)
    • Particulate matter (PM) – Primary 

Can I group multiple emissions units in the EIS report?

Grouping criteria is detailed in Engineering Guide #72. Please refer to that guide for assistance. 

If I shut down my emissions units in the beginning of the year, do I still have to report it in my EIS report for that year?

Yes. Any Title V emissions unit emitting any one of the listed pollutants (see question #1 above) will have to be reported as long as the emissions are 1 TPY or more, even if the unit only operated for one month in the reporting year. The duration of the operation does not matter, only the amount of emissions is of concern provided that the pollutant is listed above. 

Emissions Calculator

How does the Emissions Calculator calculate CAPs and HAPs?

The Air Services Emissions Calculator is designed to automate the calculation of emissions using the throughput value, the uncontrolled emissions factor, the efficiency and the uncontrolled hours of operation. It is important to note that the emissions factor needs to be an uncontrolled factor and be reported in units consistent with the material and throughput information. If the emissions factor cannot be provided in units consistent with the material and throughput information, the user needs to select an emissions method of calculation and attach the calculations in a spreadsheet.

For hazardous air pollutants (HAPs), the default calculation method is FIRE but the user can select other methods which may be pertinent to his operation. For critical air pollutants (CAPs), the user is expected to pick the best calculation method for each pollutant. In the pollutant’s list, the calculator identifies all the CAPs and only those HAPs with default emissions factors. The CAPs are listed first and the user must complete the information for all pollutants while the HAPs are listed second, and the user should review the list for completeness and make any necessary revisions. The CAPs is a mandatory reporting requirement, and the facility’s responsible official must confirm the report’s accuracy and completeness.

Which control efficiency is used to calculate HAPs?

Air Services does not require a control efficiency entry for a hazardous air pollutant (HAP) to calculate the emissions. The calculator is designed to utilize a criteria control efficiency in the calculation of HAPs emissions. These default control efficiency substitutions are provided for the user’s convenience. However, default values can be changed if the user has better data for control efficiencies for selected HAPs. The changes may be effected by modifying the facility profile for those HAPs. In those cases, the calculator will select the HAP control efficiency from the facility profile and not the default control efficiency.

In the Air Services pollutant reference table, each HAP pollutant is assigned to a category. The four category options are: hazardous air particulate matter pollutants (PM-HAP); hazardous volatile organic compound pollutants (VOC-HAP); hazardous air particulate matter/volatile organic compound pollutants (PM/VOC-HAP); and hazardous air pollutants (HAP). HAPs that belong to the PM-HAP category will utilize the PM control efficiency (i.e. metals). HAPs that belong to the VOC-HAP category will utilize the VOC control efficiency. HAPs that belong to the PM/VOC-HAP group can utilize either one control efficiency, however, there are no such pollutants in the Air Services reference table. HAPs that belong to the HAP category will assume no control efficiency (CE) in the calculation of emissions.

For selected pollutant groups, the following assumptions are made in deciding category assignment:

  1. Dioxins, furans and polycyclic aromatic hydrocarbons (PAHs) are semi-volatiles, and they are assigned to the HAP category which implies that the calculator will not apply a default CE.
  2. Glycol ethers are expected to behave the same way as VOCs, and they are assigned to the VOC-HAP group which implies that the calculator will apply the VOC CE.
  3. Mercury is a metal, but due to its importance and toxicity, it is not assigned to the PM-HAP group which implies that the calculator will not apply a default CE.

How does the calculator handle formulas based calculations?

For a number of pollutants, calculations are based on formulas. Depending on which formula is used, one or many variables will appear on the right side of the 'Material and Throughput' information table, and their numeric values are needed to complete the calculation. It is mandatory that the user enters a value for each variable.


My facility has multiple buildings, which GEP do I use?

First you need to figure out which building generate the highest Good Engineering Practice (GEP) by using this formula: GEP = H + 1.5L. Once that is obtained, the actual physical building dimensions are used for the width, height and length of the building giving the highest GEP. Keep in mind that this building may be on the facility's property or at a nearby structure. A nearby structure is defined as a structure within five times the lesser of its height or width from the stack. Structures located more than 800 meters or 2,625 feet from the stack should not be considered. Buildings with multiple segmented roofs can be viewed as multiple buildings and the same procedure would apply. For additional information, please review document "Building Downwash Analysis" [PDF]. 

Do I need GEP data if my emissions source is located outside the building?

No. Building dimensions would not be required if the source is located outside the building and is not vented through a stack. Similarly, if sources within a building are not vented through a vent pipe or stack (i.e., are released as fugitive through open doors or windows), no building dimensions would be necessary. 

What do I report if my facility does not have stacks, but only ventilators and fans?

Ventilators and fans are treated as stacks (short stacks), so the emissions egress information profile must be completed.

Quality Assurance

What is the general reporting and quality assurance rule for reporting volatile organic compounds (VOCs) and organic compounds (OCs)?

Because volatile organic compounds (VOCs) are a subset of organic compounds (OCs), the total VOC must be included in what is reported for total OC.  If only VOC was emitted, then the OC is equivalent to the VOC. Definitions of VOC and OC can be found in Ohio Administrative Code (OAC) 3745-21-01  If OCs were emitted but none of it was volatile, then the reported VOC should be zero. 

What is the general reporting and quality assurance rule for reporting particulate compounds?

An emissions unit with a particulate matter (PM) 10 filterable value higher than the PM filterable value will be rejected by Air Services.  PM10 filterable is a subset of PM filterable and subsequently the PM10 value should either be less than or equal to the PM value.