c) Changes in the administration of the State school bus inspection program and changes to federal and State law have caused the purchase or manufacture date of school buses to be critical in the application of these regulations. The effective dates for some of these standards will vary.

1. 1) Exemptions to some standards are provided for school buses purchased prior to September 1974, the effective date of the Department's "Vehicle Inspection Stations Governing School Buses."
2. 2) Exemptions to some standards are provided for school buses manufactured prior to March 1977, the date of the Department's Order "Minimum Safety Standards for Construction of Type I School Buses."
3. 3) Exemptions are provided for Type II school buses manufactured prior to October 1978, the date of the Department's Order "Minimum Safety Standards for Construction of Type II School Buses."
4. 4) Some standards are identified with other effective dates. These standards are applicable to all school buses manufactured or purchased after the identified date or during the time frame specified.