C.R.S. § 42-14-104

(1) This article applies to: (a) Commercial diesel vehicles with a gross vehicle weight rating of greater than fourteen thousand pounds that are designed to operate on highways; and (b) Locations where commercial diesel vehicles load or unload if a local authority has adopted or enacted a resolution, ordinance, or other law consistent with this article. (2) This article does not supersede an ordinance of a local authority if the authority has an average elevation of over six thousand feet and if the ordinance was in effect on January 1, 2011.