Idle Reduction Weight Exemption
Any motor vehicle equipped with a qualified auxiliary power unit (APU) or idle reduction technology may exceed the state gross, axle, tandem, or bridge weight limits by up to 550 pounds to account for the weight of the technology. The additional weight may not exceed the actual weight of the idle reduction unit. The vehicle operator must be able to provide written certification of the weight of the APU or idle reduction technology and demonstrate that the technology is fully functional.
(Reference Maryland Statutes, Transportation Code 24-109)