Gosh, I am really wondering why I am receiving a lecture from someone who does not know me. My Nitrox exam score was 100 and I can use an analyzer with ease. I am a very safe diver. I am a certified rescue diver and I am constantly watching other divers to determine if anyone needs assistance. I do not get c cards just to accumulate them. I take the courses very seriously. I sincerely appologize if I offended Pedro2 by answering Tortuga's question.