Minn. R. 7410.5160
COMMERCIAL VEHICLE EQUIPMENT SAFETY STANDARDS
Commercial motor vehicles: A. must be equipped as required by Code of Federal Regulations, title 49, section 392.7 or 392.8 or part 393; B. must have proof of a current annual inspection as required by Code of Federal Regulations, title 49, section 396.17, and, in the case of a commercial vehicle as defined in Minnesota Statutes, section 169.781 , and registered in Minnesota, must display a current Minnesota inspection decal as required in Minnesota Statutes, section 169.781 , subdivision 2; C. must have an operable parking brake, either hydraulic or air supplied, capable of holding the vehicle; and D. if equipped with air brakes, must have operable air brake systems that meet the safety standards specified in subitems (1) through (3): (1) an air loss of no more than three pounds per square inch in a single-unit vehicle, or four pounds per square inch in a combination vehicle, as determined by a one-minute, applied-pressure test; (2) a low-air warning device that activates before pressure drops below 60 pounds per square inch; and (3) an emergency brake system that activates before pressure drops below 20 pounds per square inch.