For development of alveolar PO2 of 60 mm Hg and high altitude illness to develop in an otherwise healthy person from sea level, rapid ascent to following height is required
People have different susceptible to altitude sickness,on an average it begins around 2000 to 3000 meters above sea level Ref:Guyton and Hall textbook of medical physiology 12th edition,page number:375,376
2,000 meters
3,000 meters
4,000 meters
5,000 meters
General physiology