In Colorado a drunk driving conviction can classify as either a DUI (driving under the influence) or a DWAI (driving while ability impaired). These classifications are based on a person’s blood alcohol concentration or BAC. A DUI is defined by a .08% or higher BAC and a DWAI is defined by a .05% to .08% BAC. Legal limit in Colorado: Standard, non-commercial drivers: DWAI: 0.05% Standard, non-commercial drivers: DUI: 0.08% Drivers under 21: 0.02% Penalties, Fines, & Suspension Colorado DUI & DWAI Penalties, Fines, &