However, clinical correlation is always necessary as the exact cutoff below which tissue hypoxia ensues has not been defined.
This is the danger zone, where cognitive abilities decline rapidly, personality changes occur, and motor skills are impaired.
However this does not mean that we cannot go above 33, 700 feet, as we discussed above for our normal operations in the body we require a minimum of 55 mm Hg of partial pressure what we would breathe at 10 000 feet.