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The rate of emissions of a regulated pollutant from a source or emissions unit for the calendar year, seasonal period, day or other period of time as specified, based on the best information available to the owner or operator of that emission unit. Actual emission rates include startup, shutdown or malfunction emissions. The calculation of actual emissions must follow an "emission determination method." Where, for any reason, a source has measured any of its emissions, the source must report the measured total as its "actual emissions" for those pollutants rather than using an estimation method to derive the total for that period of time during which the measurements were taken.


Any solid, liquid or gaseous matter, any odor or any form of energy that is capable of being released into the atmosphere from an emission source.


The emission rate of a source calculated using the maximum rated capacity of the source, subject to enforceable permit conditions or other enforceable limits and any applicable emission standards adopted by 35 Ill. Adm. Code, Subtitle Chapter B, or the USEPA under Section 113 of the Clean Air Act. If a source is not subject to permit conditions or emission standards, the allowable emissions are assumed to be the source's maximum emissions.


Standards promulgated by the Pollution Control Board pursuant to authority found in 35 Ill. Adm. Code 243 or by the USEPA pursuant to authority found in the Clean Air Act and its amendments.


The individual responsible for the certification of the accuracy of the Annual Emission Report and who will take legal responsibility for the information verified or reported in the Annual Emission Report.


The Clean Air Act of 1970, as amended by the amendments of 1977 and 1990.


Information submitted under the Environmental Protection Act, which is not a trade secret nor privileged information, and which is accorded confidential treatment for business or privacy purposes. For further definition of confidential data, see 35 Ill. Adm. Code 130.


Equipment, such as an afterburner, absorber, scrubber, condenser, cyclone or baghouse used to remove or prevent the emission of pollutants from a contaminated air stream. Control devices also may include methods and procedures used to reduce pollutant emissions (such as water sprays used for dust suppression).


Pollutants discharged into the atmosphere from smokestacks, manufacturing processes, vents, and surface areas of commercial or industrial facilities and other stationary sources.


Information necessary to determine the identity, amount, frequency, concentration or other characteristics of the emission which, under an applicable standard or limitation, the source was authorized to emit. A general description of the location and/or nature of the source to the extent necessary to identify the source and distinguish it from other sources.


Specific data fields related to emission parameters and facility identification which the IEPA presently considers to constitute emissions data are listed in the following paragraphs:

Emission parameters:

  1. Emission type
  2. Emission rates of all pollutants (tpy, lb/day, and lb/hr)
  3. Estimated emissions method
  4. Calendar year for the emissions
  5. Release height
  6. Stack or vent diameter at point of emission
  7. Release velocity
  8. Release temperature
  9. Frequency of release
  10. Duration of release
  11. Concentration, expressed as ppm, volume percent, or weight percent
  12. Density of emissions stream or average molecular weight
  13. Boiler or process design capacity
  14. Emissions estimation methods
  15. Percent space heat
  16. Hourly maximum design rate

Facility identification:

  1. Full name, physical location and mailing address of the source
  2. Latitude and longitude
  3. SIC code

Please refer to 40 CFR 56.7042 (1991) for more information on emissions data.


Total quantity of any air contaminant discharge into the atmosphere in a given period.


The portion of the Annual Emission Report that contains data fields for source identification, total actual emissions of regulated air pollutants emitted by the source, permit information, and the certification block that includes the signature of the certifying individual.


Any part or activity of a stationary source that emits or has the potential to emit any regulated air pollutant. The term " POINT" is used on the Annual Emission Report forms to indicate an emission unit. A unique, four-digit number is assigned to each emission unit or point by the DAPC database.


A geographic area that does not meet one or more of the National Ambient Air Quality Standards for the criteria pollutants specified in the Clean Air Act.


Organic materials or compounds that have been determined to have negligible photochemical reactivity but are still regulated pollutants and must be reported in the Annual Emission Report. Nonvolatile organic materials include the following specific chemicals or groups of chemicals:

  • Chlorodifluoroethane (HCFC-142b)
  • 1-chloro-1-fluoroethane (HCFC-151a)
  • Chlorodifluoromethane (CFC-22)
  • Chlorofluoromethane (HCFC-31)
  • Chloropentafluoroethane (CFC115)
  • 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124)
  • Decafluoropentane (HFC 43-10mee)
  • Dichlorodifluoromethane (CFC-12)
  • Dichlorofluoroethane (HCFC-141b)
  • Dichlorotetrafluoroethane (CFC-114)
  • Dichlorotrifluoroethane (HCFC-123)
  • 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a)
  • 1,1-difluoroethane (HFC-152A)
  • Difluoromethane (HFC-32)
  • 2-(difluoromethoxymethyl)-1,1,1,2,3,3,3-heptafluoropropane
  • 1-ethoxy-1,1,2,2,3,3,4,4,4-nonafluorobutane
  • 2-(ethoxydifluoromethyl)-1,1,1,2,3,3,3-heptafluoropropane
  • Ethylfluoride (HFC-161)
  • Ethane
  • 1,1,1,2,3,3-hexafluoropropane (HFC-236ea)
  • 1,1,1,3,3,3-hexafluoropropane (HFC-236fa)
  • Methane
  • Methyl acetate
  • Methylene chloride (dichloromethane)
  • 1,1,1,3,3-pentafluorobutane (HFC-365mfc)
  • Pentafluoroethane (HFC-125)
  • Pentafluoropropane (HCFC-225ca)
  • Pentafluoropropane (HCFC-225cb)
  • 1,1,2,2,3-pentafluoropropane (HFC-245ca)
  • 1,1,2,3,3-pentafluoropropane (HFC-245ea)
  • 1,1,1,2,3-pentafluoropropane (HFC-245eb)
  • 1,1,1,3,3-pentafluoropropane (HFC-245fa)
  • Perchlorethylene
  • Perfluorocarbon parachlorobenzotrifluoride (PCBTF)
  • Tetrafluoroethane (HFC-134a)
  • 1,1,2,2-tetrafluoroethane (HFC-134)
  • 1,1,1-trichloroethane (methyl chloroform)
  • 1,1,1-trifluoroethane (HFC-143a)
  • Trichlororofluoromethane (CFC-11)
  • Trichlorotrifluoroethane (CFC-113)
  • Trifluoromethane (HFC-23)
  • Completely fluorinated cyclic, branched, or linear alkanes
  • Completely fluorinated cyclic, branched, or linear ethers with no unsaturations
  • Completely methylated cyclic, branched, or linear siloxanes
  • Completely fluorinated cyclic, branched, or linear tertiary amines with no unsaturations
  • Sulfur containing perfluorocarbons with no unsaturations and with sulfur bonds only to carbon and fluorine.


Any solid or liquid material, other than water, which exists in finely divided form.


Particulate matter with an aerodynamic diameter less than or equal to ten micrometers, as measured by the applicable test methods specified by the rule.


"Peak ozone season" means the months of June, July and August.


The capability of a source to emit a pollutant at maximum design capacity, except as constrained by enforceable permit conditions that include restrictions on the hours of operation and the type or amount of material combusted, stored or processed, or the installation of air pollution control equipment.


Pollutants for which National Ambient Air Quality Standards or specific regulations limiting emissions are established. This is further defined under Section 39 of the Illinois Environmental Protection Act. A current list of hazardous air pollutants may be found here.


Standard Industrial Classification code. A series of codes devised by the Office of Management and Budget (OMB) to classify establishments according to the type of economic activity in which they are engaged.


All of the pollutant emitting activities that are located on one or more contiguous or adjacent properties and are under the control of the same person.


The report that the IEPA provides to the source that lists data fields for the information required in the Annual Emission Report and contains the information, if any, that previously has been reported to the IEPA for those data fields.


Any building, structure, facility, plant, or installation which emits, or may emit, any air pollutant subject to regulation under the Clean Air Act; an emission source that is not self-propelled.


A heavy, pungent, colorless, gaseous air pollutant formed primarily by the combustion of fossil fuels.


The whole or any portion or phase of any scientific or technical information, design, process (including a manufacturing process), procedure, formula or improvement, or business plan that is secret in that it has not been published or disseminated or otherwise become a matter of general public knowledge, and which has competitive value. A trade secret is presumed to be secret when the owner takes reasonable measures to prevent it from becoming available to persons other than those selected by the owner to have access thereto for limited purposes. For further definition of trade secret, see 35 Ill. Adm. Code 130.


Any compound of carbon (excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate) that participates in atmospheric photochemical reactions and is not specifically designated by the USEPA as having negligible photochemical reactivity.