Notwithstanding the provisions of this chapter to the contrary, Parts 390 through 397, Title 49, Code of Federal Regulations, shall not apply to commercial motor vehicles operated in intrastate commerce to transport property which have a gross vehicle weight rating or gross combination weight rating of twenty-six thousand (26,000) pounds or less. The exception provided by this section shall not apply to vehicles transporting hazardous materials required to be placarded, or to vehicles designed to transport sixteen (16) or more passengers, including the driver, as defined in Title 49 of the Code of Federal Regulations.