I don't know the lower limit for the CAA medical but if your Hb is on the low side may I suggest you take a look at your diet - does it contain plenty of iron-rich foods, Folic Acid and Vitamin C? If it does, then go and see your GP - it would probably be a good idea to do this anyway and ask him to recheck your Hb for you. Your GP will then be better able to take things futher if necessary.