1. The oxygen concentration increases by 1% (under normal pressure, the oxygen concentration is 21%), it's like a 350-meter drop by altitude.

2. The composition of air at high altitude is that the same as that at low altitude. apart from water vapour, oxygen accounts for about 21% and nitrogen accounts for about 79%. But the high altitude air is thin, therefore the absolute concentration of oxygen is additionally thin.

3. The oxygen concentration below 25% is analogous to the oxygen content within the air and has no therapeutic value.

4. Oxygen inhalation concentration: oxygen accounts for 20.93% within the air, CO2 0.03%, and therefore the remaining 79.04% is nitrogen, hydrogen and trace inert gases. Grasping the oxygen concentration plays a crucial role in correcting hypoxia.

5. The conversion algorithm of oxygen concentration and oxygen flow are often calculated by the subsequent formula: oxygen concentration of blood gas analysis

The current oxygen inhalation method is open oxygen inhalation thanks to the nasal oxygen tube inhalation. That is, when an individual takes a breath, the quantity of oxygen can't be supplied, and a few air (21% oxygen concentration) are going to be inhaled next thereto, and it actually reaches the lungs. The oxygen concentration within the part is that the oxygen concentration after mixing air, which is that the inhaled oxygen concentration.

Inhaled oxygen concentration=21+4*flow rate*oxygen purity

6. The connection between oxygen flow and oxygen concentration are often found within the table (calculated supported the above formula):

7. Relationship between altitude and oxygen purity

8. Oxygen concentration and oxygen partial pressure:

In the water level area, the atmospheric pressure per square centimeter is 101.3kPa (760 mmHg). In dry air, oxygen accounts for 20.40%, therefore the oxygen partial pressure is 21.15kPa (159 mmHg). The proportion of oxygen within the air is essentially not suffering from the plateau. When the air pressure decreases thanks to the rise in altitude, the partial pressure of oxygen decreases proportionally.