If you are a trainee or apprentice, you can apply for a Red CSCS Card. If you are still considered an unskilled HVACR worker but you are no longer a trainee, a Green CSCS Card is probably the best option. If you are already a skilled technician, you can apply for a Blue CSCS Card. Supervisors should aim to obtain a Gold CSCS Card whilst those in managerial positions should really be looking to acquire a Black CSCS Card.