# 35 Ill. Adm. Code 203.104: Section 203.104 Actual Emissions

> Illinois · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_104

## Section

- **Citation:** 35 Ill. Adm. Code 203.104
- **Heading:** Section 203.104 Actual Emissions
- **Jurisdiction:** Illinois
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Illinois Administrative Code / Title 35 ENVIRONMENTAL PROTECTION / CHAPTER I: POLLUTION CONTROL BOARD / Part 203 MAJOR STATIONARY SOURCES CONSTRUCTION AND MODIFICATION / Section 203.104 Actual Emissions

## Text

Section 203
Section 203.104  Actual
Emissions
"Actual Emissions"
means the actual rate of annual emissions of a pollutant from an emissions unit
as of a particular date.  Actual emissions are equal to the average rate, in
tons per year, at which the emissions unit actually emitted the pollutant
during the two-year period which immediately precedes the particular date or
such other period which is determined by the Illinois Environmental Protection
Agency (Agency) to be representative of normal source operation.  Actual
emissions shall be calculated using the unit's actual operating hours,
production rates, and types of materials processed, stored or combusted during
the selected time period; however:
a)         The Agency shall allow the use of a different time period upon
a demonstration by the applicant to the Agency that the time period is more
representative of normal source operation.  Such demonstration may include, but
need not be limited to, operating records or other documentation of events or
circumstances indicating that the preceding two years is not representative of
normal source operations.
b)         The Agency may presume in the absence of reliable data on
actual emissions that the source-specific allowable emissions for the emissions
unit are equivalent to the actual emissions of the emissions unit.
c)         For any emissions unit which has not begun normal operations
on the particular date, the Agency shall presume that the potential to emit of
the emissions unit is equivalent to the actual emissions on that date.

## Nearby sections

- [35 Ill. Adm. Code 203.100 Section 203.100  Effective Dates](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_100.md)
- [35 Ill. Adm. Code 203.101 Section 203.101  Definitions](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_101.md)
- [35 Ill. Adm. Code 203.103 Section 203.103  Actual Construction](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_103.md)
- [35 Ill. Adm. Code 203.104 Section 203.104  Actual Emissions](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_104.md)
- [35 Ill. Adm. Code 203.107 Section 203.107  Allowable Emissions](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_107.md)
- [35 Ill. Adm. Code 203.110 Section 203.110  Available Growth Margin](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_110.md)
- [35 Ill. Adm. Code 203.112 Section 203.112  Building, Structure and Facility](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_112.md)
- [35 Ill. Adm. Code 203.113 Section 203.113  Commence](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_113.md)
- [35 Ill. Adm. Code 203.116 Section 203.116  Construction](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_116.md)
- [35 Ill. Adm. Code 203.117 Section 203.117  Dispersion Enhancement Techniques](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_117.md)
- [35 Ill. Adm. Code 203.119 Section 203.119  Emission Baseline](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_119.md)
- [35 Ill. Adm. Code 203.121 Section 203.121  Emission Offset](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_121.md)
- [35 Ill. Adm. Code 203.122 Section 203.122  Emissions Unit](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_122.md)
- [35 Ill. Adm. Code 203.123 Section 203.123  Federally Enforceable](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_123.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P203_S203_104. Check the current official text before relying on it. Not legal advice.