Oxygen Toxicity
![never use pure oxygen while diving](images/o2.png)
We all need oxygen to survive, but too much oxygen can lead to serious conditions such as convulsions and death. This limit is well in excess of 100% oxygen, so we don't need to be concerned about oxygen toxicity on land, even when administering oxygen for first aid.
However, as you descend, the density of the air you breathe increases. This allows your blood cells to carry more air molecules than at the surface. When your cells carry a certain amount of oxygen, your body can have adverse reactions such as convulsions. This can lead to more serious consequences such as drowning.
Oxygen toxicity can be avoided by never filling your cylinder with pure oxygen, and diving within safe depth limits. Pure oxygen becomes toxic at about 20 feet, and the oxygen in normal air becomes toxic at about 218 feet. Notice that this is well beyond the maximum recreational diving depth of 130 feet.
However, as you descend, the density of the air you breathe increases. This allows your blood cells to carry more air molecules than at the surface. When your cells carry a certain amount of oxygen, your body can have adverse reactions such as convulsions. This can lead to more serious consequences such as drowning.
Oxygen toxicity can be avoided by never filling your cylinder with pure oxygen, and diving within safe depth limits. Pure oxygen becomes toxic at about 20 feet, and the oxygen in normal air becomes toxic at about 218 feet. Notice that this is well beyond the maximum recreational diving depth of 130 feet.