That is what I would like to double check, in Normal is any O2 used(for various A/C types) at normal cabin altitude.
According to this article....
http://aviationweek.com/bca/it-s-not-about-breathing
"It is more instructive to discuss what the regulator does for the pilot in the “normal” position. How much oxygen are we receiving sitting on the ground? How about at altitudes like 10,000 ft., 18,000 ft., 30,000 ft. and 43,000 ft.?
Let’s assume the oxygen regulator has been designed to produce oxygen at a partial pressure of 3.0 psi to the lungs of the pilot. At sea level that’s the pressure that already exists, so the regulator, in “normal,” delivers ambient air to the pilot at a cabin altitude of sea level. This is why I used to smile when I heard certain European inspectors would check the oxygen remaining to insure crews had oxygen masks on when above FL 370. At the cabin altitude that a properly functioning pressurization system would provide at FL 370, the regulator would be delivering almost completely ambient cabin altitude to the pilot and the amount of oxygen used wouldn’t decrease noticeably over several hours."