(a) A motor vehicle subject to department inspection requirements shall not be operated unless it displays on the interior surface of the windshield, as close to the lower right hand corner as practicable,^* an unexpired certificate of inspection issued to the current owner or operator by the department, or by another regulatory body certified by the department. In lieu of such certificate of inspection, the department shall recognize the display of a valid certificate of inspection issued within the preceding six months for a motor vehicle having a seating capacity of more than 10 passengers engaged in interstate commerce by the following:

(b) Motor vehicles shall be presented for inspection at the time and place designated by a duly authorized representative of the department. Adequate inspection facilities must be provided by the operator of the vehicles to be inspected.

(c) A newly transferred vehicle shall not be operated by the new operator until subdivision (a) of this section has been complied with or has secured written approval from this department.

(d) Motor vehicles failing to meet the inspection standards of the department as contained in the out-of-service criteria listed in section 720.11 of this Part shall be declared and marked out-of-service by the department inspector placing an out-of-service vehicle sticker on the windshield. Vehicles marked with an out-of-service sticker shall not be operated with passengers until the defects noted have been repaired and checked by a department inspector. The out-of-service sticker shall be removed only by the department inspector certifying that the vehicle is safe to operate and issuing a valid certificate of inspection. Out-of-service vehicle stickers shall only be valid for 15 days after issuance for the purpose of moving the vehicle on public roadways for the purpose of repairing the vehicle. In the case where the department inspector determines that the motor vehicle may not be operated safely on a public highway without first being repaired, the inspector also shall place a highway operation prohibited sticker on the windshield. Such vehicle shall not be operated until the critical safety defect(s) identified by the department inspector is repaired.