As a subject matter expert in respiratory therapy, I can provide you with an accurate answer to your question regarding the percentage of oxygen in 1 liter. In standard atmospheric conditions, room air contains approximately 21% oxygen. Medical oxygen sources can deliver oxygen at various flow rates, typically ranging from 1 liter per minute (L/min) to 5 liters per minute (L/min). Each liter per minute of oxygen delivered increases the oxygen concentration in the air the patient breathes by approximately 3 to 4 percent. Using the information provided, if we consider the lower end of the increase (3% per liter), 1 liter of oxygen would increase the oxygen concentration by 3%. If we consider the higher end (4% per liter), 1 liter of oxygen would increase it by 4%. However, these percentages are relative to the baseline oxygen concentration in room air, which is 21%. So, if a patient is receiving 1 liter of oxygen per minute, they would be breathing air with an oxygen concentration of approximately 24% (21% room air + 3% from 1 L O2) or 25% (21% room air + 4% from 1 L O2). Here is the answer with the important values highlighted: Room air is 21% O2. Every liter/minute of oxygen increases the percentage of O2 by 3 to 4%. So, 1 liter of oxygen would increase the oxygen concentration by approximately 3 to 4 percent. read more >>

Standard oxygen sources can deliver from ? liter per minute of O2 to 5 liters/minute (L/min). Every liter/minute of oxygen increases the percentage of O2 the patient breathes by 3 �C 4 %. Room air is 21% O2. So if a patient is on 4 L/min O2 flow, then he or she is breathing air that is about 33 �C 37% O2.read more >>