CO Code § 25-12-110 (2021)
2021 Colorado Code|Title 25 - Public Health and Environment|Article 12 - Noise Abatement|§ 25-12-110. Off-Highway Vehicles

  An off-highway vehicle operated within the state shall not emit more than the following level of sound when measured using SAE J1287:   If manufactured before January 1, 1998 =lf 99 db(A);    If manufactured on or after January 1, 1998 =lf 96 db(A).       A snowmobile shall not emit more than the following level of sound when measured using SAE J2567:   If manufactured on or after July 1, 1972, and before July 2, 1975 =lf 90 db(A);    If manufactured on or after July 2, 1975 =lf 88 db(A).         A person shall not sell or offer to sell a new off-highway vehicle that emits a level of sound in excess of that prohibited by subsection (1) of this section unless the off-highway vehicle complies with federal noise emission standards. A person shall not sell or offer to sell a new snowmobile that emits a level of sound in excess of that prohibited by subsection (2) of this section unless the snowmobile complies with federal noise emission standards.    For the purposes of this section, a “new” snowmobile or off-highway vehicle means a snowmobile or off-highway vehicle that has not been transferred on a manufacturer's statement of origin and for which an ownership registration card has not been submitted by the original owner to the manufacturer.       This section shall not apply to the following:   A vehicle designed or modified for and used in closed-circuit, off-highway vehicle competition facilities;    An off-highway vehicle used in an emergency to search for or rescue a person; and    An off-highway vehicle while in use for agricultural purposes.       [ ] A person who violates this section commits a class 2 petty offense and, upon conviction thereof, shall be punished by a fine of not more than one hundred dollars.    No municipality or county may adopt an ordinance or resolution setting noise standards for off-highway vehicles or snowmobiles that are more restrictive than this section.      Nothing in this section shall be construed to modify the authority granted in section 25-12-103.    Nothing in this section shall be construed to authorize the test to produce a less restrictive standard than the J1287 stationary sound test or the J2567 stationary sound test published by SAE international or any successor organization.       The following shall be an affirmative defense to a violation under this section if the off-highway vehicle or snowmobile:   Was manufactured before January 1, 2005;    Complied with federal and state law when purchased;    Has not been modified from the manufacturer's original equipment specifications or to exceed the sound limits imposed by subsection (1) or (2) of this section; and    Does not have a malfunctioning exhaust system.        Editor's note: This version of subsection (5) is effective until March 1, 2022.  (5) [ ] A person who violates this section commits a civil infraction.  Editor's note: This version of subsection (5) is effective March 1, 2022.   History. Source: L. 2008: Entire section added, p. 2103, § 5, effective July 1, 2010. L. 2021: (5) amended,(SB 21-271), ch. 462, p. 3239, § 471, effective March 1, 2022.    Editor's note:   Section 803(2) of chapter 462 (SB 21-271), Session Laws of Colorado 2021, provides that the act changing this section applies to offenses committed on or after March 1, 2022.