Using EANx Regulator with Air

[DiveCaptDean]

Scott gave you the most politically correct answer and i will also urge you to take these questions to your class and make sure you get them answered to your satisfaction.  Your dive center and your instructor are defintely the best places to increase your knowledge and  to get answers to your questions.  I will let you know that the biggest concerns for oxygen clean regs and equipment are for mixes that are greater than 40% O2....you will be able to use your current regulator for both air and the nitrox mixes that you will be training for.  Regarding  your other question on depth...you will need to save that for your class..you will learn about maximum depths for a particular breathing mixture..it will all become clear to you...Get through the class...and let us know how your blue hole dives go.
Deano