To move to the Professional Classes, one should have at least 3 years working experience after graduation.
-TPE (Training Professional Engineer) to PE (Professional Engineer)
-TPET (Trainee Professional Engineering Technologist) to PET (Professional Engineering Technologist)
-TET (Trainee Engineering Technician) to ET (Engineering Technician)
-TEC (Trainee Engineering Craftsman) to EC (Engineering Craftsman)