Lesson 1, Topic 1
In Progress

Oxygen Intoxication

When we talk about oxygen poisoning we are referring to the toxicity of oxygen in our body, but within the course CMAS One Star Diver serves only to alert the possibility of existence of it, because only occur at depths higher than the maximum limit of 20m where the diver CMAS One Star Diver can not dive.

One of the diving specialties you can attend in order to understand the effects of enriched air mixtures, known as Nitrox or EAN – Enriched Air Nitrox is the CMAS Nitrox Diver certification


Sometimes intoxication immediately manifests itself by seizures similar to those of epilepsy, but most often this condition is preceded by the following symptoms:

  • Generalized muscle tremor, especially of the lips
  • Dizziness and nausea
  • Ringing
  • Tubular vision
  • Difficulty breathing
  • Irritability

Neurological toxicity (Paul Bert effect) is extremely variable, and there is no fixed criterion of oxygen exposure in which neurological toxicity is assumed to arise, for the purposes of diving planning are assumed at partial pressures limit between 1.4 and 1.6 bar.

In effortless dives and in hot waters, breathing pure oxygen (100%) this intoxication can arise at 6 meters deep and breathing air (21% oxygen) may arise between 56 meters depth for partial oxygen pressure at 1.4 bar and 66 meters deep for partial oxygen pressure at 1.6 bar.