PpN₂ — Partial Pressure of Nitrogen

The partial pressure of nitrogen (PpN2) is the actual force exerted by nitrogen molecules within your breathing gas. While air contains 78% nitrogen, the pressure increases as you go deeper because the total ambient pressure rises.

This value dictates how much nitrogen dissolves into your blood and tissues. At 10 m depth, the PpN2 is 1.76 bar. If you dive to 30 m, this number jumps to 3.12 bar. This change directly affects your decompression requirements and narcosis levels.

Watch your depth closely. You might feel nitrogen narcosis at 30 m because the PpN2 is high enough to impair your cognitive function. Always use a dive computer to track these changes during your descent.