35 Ill. Adm. Code 276.501
General Requirements
Section 276
Section 276.501 General
Requirements
Compliance with Illinois vehicle
test standards shall be determined by following the test procedures set forth
in Subpart B of this Part and by utilizing the following:
a) Steady-state idle test equipment meeting the specifications set
forth in Sections 276.502 and 276.503 of this Part and the evaporative system
test equipment meeting the specifications set forth in Section 276.504 of this
Part; or
b) On-road remote sensing test equipment meeting the specifications
set forth in Section 276.507 of this Part; or
c) OBD test equipment meeting the specifications set forth in
Section 276.508 of this Part.