Colorado § 42-4-403 - Powers and duties of the commission.
Full text of Colorado Colorado Revised Statutes § 42-4-403 — Powers and duties of the commission., with citation guidance and answers to common questions.
§ 42-4-403. Powers and duties of the commission.
(1) The commission shall be responsible for the adoption of rules and regulations which are necessary to implement the diesel inspection program including:
(a) Regulations governing procedures for:
(I) Testing and licensing of diesel emissions inspectors;
(II) Licensure of diesel emission inspection stations;
(III) Standards and specifications for the approval, operation, calibration, and certification of exhaust smoke opacity meters;
(IV) Proper performance of diesel opacity inspections and emissions system control inspections;
(b) Issuance of the following types of certifications of emissions control by licensed diesel emission inspectors:
(I) A certification of diesel smoke opacity compliance if, at the time of inspection, the smoke opacity from a diesel vehicle is in compliance with the applicable smoke opacity limits;
(II) A certification of diesel smoke opacity waiver if, at the time of inspection, the smoke opacity from a diesel vehicle does not comply with the applicable smoke opacity limits but such vehicle is adjusted or repaired to specifications as provided by regulation of the commission;
(III) A temporary certification of diesel smoke opacity compliance for diesel vehicles required to be repaired, if such repairs are delayed due to the unavailability of needed parts. The results of the initial smoke opacity test and final test shall be given to the owner of the diesel vehicle and reported to the department of public health and environment.
(2) (a) The commission shall promulgate and from time to time revise regulations on inspection procedures and smoke opacity limits when such procedures and limits have been proven cost-effective and air pollution control-effective on the basis of best available scientific research.
(b) Smoke limits shall not require unreasonable levels of emissions performance for a properly operated and maintained diesel vehicle of a given model year and technology, and such smoke limits shall be no less than twenty percent for five seconds minimum.
(c) The commission may also develop peak smoke opacity limits, but such limits shall not be less than forty percent for less than one second.
(d) Notwithstanding any other provisions of this subsection (2), for inspections conducted between January 1, 1990, and December 31, 1990, the smoke opacity limits shall be forty percent for five seconds minimum, and no diesel vehicle shall fail the smoke opacity inspection for peak limits.
(3) (a) The commission shall annually evaluate the diesel inspection program to determine but not limit the number of diesel vehicles which fail to meet the applicable smoke opacity limits after adjustments and repairs.
(b) If the commission finds that a significant number of diesel vehicles do not meet the applicable smoke opacity limits after adjustments or repairs are made, the commission shall develop recommendations designed to improve the air pollution control-effectiveness of the diesel inspection program in a cost-effective manner and shall submit such recommendations to the general assembly.
(4) In addition to any other authority granted under this section, the commission shall adopt regulations requiring each licensed diesel emissions inspection station to post, at the station, in a clearly legible manner and in a conspicuous place, the fee which shall be charged for performing a diesel emission-opacity inspection.
(5) The commission may exempt diesel vehicles of any make, model, or model year from the provisions of the diesel inspection program when inspection would be inappropriate for such vehicles. The exemption may include diesel vehicles which are required to be registered and inspected January, 1990.
(6) (a) Notwithstanding any other provisions to the contrary, the commission shall not have authority to adopt emission standards or implement an inspection and maintenance program that would result in emission requirements or an in-use testing or compliance demonstration that would be more stringent than the emission standards and test procedures adopted by the United States environmental protection agency for the corresponding model year and class of vehicle or engine.
(b) The commission shall determine by accepted scientific analysis that any emission standards and in-use test procedures it may adopt shall be designed so that any engine or vehicle which would pass the appropriate federal certification test shall also pass the inspection and maintenance test adopted by the commission for that engine or vehicle.
Source: L. 94: Entire title amended with relocations, p. 2316, § 1, effective January 1, 1995. L. 2003: (2)(c) amended, p. 1025, § 4, effective August 6.
Editor's note: This section is similar to former § 25-7-602 as it existed prior to 1994, and the former § 42-4-403 was relocated to § 42-4-503.
Source: official Colorado text · Last verified 2026-08-27
Frequently Asked Questions About Colorado § 42-4-403
What does Colorado Revised Statutes § 42-4-403 cover?
Section 42-4-403 ("Powers and duties of the commission.") is part of the Colorado Revised Statutes, the codified statutory law of Colorado. It sets out the legal rule or procedure described in the text above. Statutes are amended regularly, so always verify against the official source.
How do I cite Colorado § 42-4-403?
A common citation format is "Colorado Revised Statutes § 42-4-403" (Colorado). Legal writing may require the code abbreviation, section number, and year or edition. Match the style required by your court, professor, or publisher.
Is this the official text of Colorado law?
No. This page is for research and education and may not include the most recent amendments. For official current law, check the Colorado official source linked on this page or consult a licensed Colorado attorney.
How does Colorado § 42-4-403 apply to my situation?
Statutes are interpreted in context, and application depends on your specific facts. Only a licensed attorney in Colorado can advise on how this section applies to you. Contact your state or local bar association for a referral.
Sources & Verification
Not legal advice. Verify against the official source and consult a licensed attorney in Colorado.