40-60% Humidty is the guideline when your plants are flowering. A Humidity range of 60-70% is advisable for vegative growth, and a higher range of 80-95% for clones.
No probs mate, I suggest you get yourself a grow bible, they are invaluable, the one i use is Marijuana Horticulture The Indoor/Outdoor Medical Growers Bible. By Jorge Cervantes.