Ill. Admin. Code tit. 35 § 201.102
"Air Contaminant": 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.
"Air Pollution Control Equipment": any equipment or facility of a type intended to eliminate, prevent, reduce or control the emission of specified air contaminants to the atmosphere.
"Air Pollution": the presence in the atmosphere of one or more air contaminants in sufficient quantities and of such characteristics and duration as to be injurious to human, plant or animal life, to health, or to property, or to unreasonably interfere with the enjoyment of life or property.
"Ambient Air": that portion of the atmosphere external to buildings comprising emission sources.
"Ambient Air Quality Standard": those standards promulgated from time to time by the Pollution Control Board (Board) pursuant to authority contained in the Act and found at 35 Ill. Adm. Code 243, or by the United States Environmental Protection Agency (USEPA) pursuant to authority contained in 42 U.S.C. 7401 et seq. as amended from time to time.
"Clean Air Act": the Clean Air Act of 1970, as amended, including the Clean Air Act Amendments of 1977, as amended ( 42 U.S.C. 7401 et seq.).
"Commence": the act of entering into a binding agreement or contractual obligation to undertake and complete, within a reasonable time, a continuous program of construction or modifications.
"Construction": commencement of on-site fabrication, erection or installation of an emission source or of air pollution control equipment.
"Emission Source": any equipment or facility of a type capable of emitting specified air contaminants to the atmosphere.
"Existing Air Pollution Control Equipment": any air pollution control equipment, the construction or modification which has commenced prior to April 14, 1972.
"Existing Emission Source": any emission source, the construction or modification of which has commenced prior to April 14, 1972.
"Modification": any physical change in, or change in the method of operations, of an emission source or of air pollution control equipment which increases the amount of any specified air contaminant emitted by such source or equipment or which results in the emission of any specified air contaminant not previously emitted. It shall be presumed that an increase in the use of raw materials, the time of operation or the rate of production will change the amount of any specified air contaminant emitted. Notwithstanding any other provisions of this definition, for purposes of permits issued pursuant to Subpart D, the Illinois Environmental Agency (Agency) may specify conditions under which an emission source or air pollution control equipment may be operated without causing a modification as herein defined, and normal cyclical variations, before the date operating permits are required, shall not be considered modifications.
"New Air Pollution Control Equipment": any air pollution control equipment, the construction or modification of which is commenced on or after April 14, 1972.
"New Emission Source": any emission source, the construction or modification of which is commenced on or after April 14, 1972.
"Owner or Operator": any person who owns, leases, controls or supervises an emission source or air pollution control equipment.
"Person": any individual, corporation, partnership, firm, association, trust, estate, public or private institution, group, agency, political subdivision of this State, any other State or political subdivision or agency thereof or any legal successor, representative, agent or agency of the foregoing.
"PSD Increment": the maximum allowable increase over baseline concentration of any air contaminant as determined by Section 163 of the Clean Air Act ( 42 U.S.C. 7473 ) and regulations adopted thereunder.
"Specified Air Contaminant": any air contaminant as to which this Subtitle contains emission standards or other specific limitations and any contaminant regulated in Illinois pursuant to Section 9.1 of the Act.
"Standard Industrial Classification Manual": the Standard Industrial Classification Manual (1972), Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402.
Ill. Admin. Code tit. 35, § 201.102
Amended at 15 Ill. Reg. 17699, effective November 26, 1991