Division (b) Clearances issued by air traffic control units shall provide separation:

1. (1)

   between all flights in airspace Classes A and B;

2. (2)

   between IFR flights in airspace Classes C, D and E;

3. (3)

   between IFR flights and VFR flights in airspace Class C;

4. (4)

   between IFR flights and special VFR flights;

5. (5)

   between special VFR flights unless otherwise prescribed by the competent authority;

except that, when requested by the pilot of an aircraft and agreed by the pilot of the other aircraft and if so prescribed by the competent authority for the cases listed under b) above in airspace Classes D and E, a flight may be cleared subject to maintaining own separation in respect of a specific portion of the flight below 3 050 m (10 000 ft) during climb or descent, during day in visual meteorological conditions.