Gas Management
Nitrox MOD Calculator
Calculate where a gas reaches the selected PPO2 threshold. The result does not determine whether the gas or dive is safe overall.
Technical Diving
Extend the calculator range to 200m, raise the maximum PPO2 to 2.0 ATA, and show technical gas presets
%
Allowed range: 21 to 100 %.
ATA
Allowed range: 1 to 1.6 ATA.
m
Allowed range: 1 to 40 m.
PPO2 threshold only
This result finds the depth where the entered mix reaches the selected PPO2 threshold. It does not assess cumulative oxygen exposure, gas density, narcosis, decompression, equipment, or training limits, and is not permission to use the gas or depth.
About MOD
Maximum Operating Depth (MOD) is the calculated depth where a gas mix reaches a selected partial-pressure-of-oxygen threshold. By itself, it is not a safe-depth determination.
Where
- selected partial pressure of oxygen (ATA)
- oxygen fraction, not percentage (0.32 for EAN32)
- 10 m of seawater per atmosphere
The calculator rounds the result down so it never overstates the limit.
Common PPO2 Planning References
PPO2 > 1.6 ATA
Outside common scuba planning ranges
PPO2 1.4-1.6 ATA
Often reserved for decompression exposure under applicable training
PPO2 ≤ 1.4 ATA
Common recreational working threshold; not an all-hazards check