Editing Nitrox (section)

===MOD===
{{Main|Maximum operating depth}}
Maximum Operating Depth (MOD) is the maximum safe depth at which a given nitrox mixture can be used. MOD depends on the allowed partial pressure of oxygen, which is related to exposure time and the acceptable risk assumed for central nervous system oxygen toxicity. Acceptable maximum ppO<sub>2</sub> varies depending on the application:<ref name="dan" />
* 1.2 is often used in closed circuit rebreathers.
* 1.4 is recommended by several recreational training agencies for ordinary scuba diving.
* 1.5 is allowed for commercial diving in some jurisdictions.
* 1.6 is allowed for technical diving decompression stops, and is the recommended maximum according to NOAA<ref name="noaa" />
Higher values are used by commercial and military divers in special circumstances, often when the diver uses surface supplied breathing apparatus, or for treatment in a chamber, where the airway is relatively secure.