The High Altitude Supplemental Oxygen (HASO) working group is asking professional pilots to answer survey questions related to supplemental oxygen use required by FAR 91.211. The survey asks questions about the respondent’s type of flying, then presents various scenarios to assess the respondent’s understanding of 91.211. This is followed by questions about compliance with the regulation, which many pilots admit they don’t do, and questions about hazards caused by compliance, such as compromising communications and unnecessarily depleting the emergency oxygen supply.

According to the HASO working group, “The primary objective of the HASO Working Group is to provide a best-practice recommendation to the U.S. FAA for operations above 41,000 feet in aircraft certified to a ceiling of 51,000 feet. This group's recommendations will be based on risk analysis as it applies to a comprehensive evaluation of all exposure to hazards above 41,000 feet.”

In an article published in AIN in 2010, corporate pilot Chris Shaver provided results of his master’s degree thesis, which included a survey of pilots about oxygen use. In his thesis, Shaver found that more than 60 percent of business jet pilots do not use oxygen masks when required by FAA regulations. 

EASA regulations are less prescriptive than the rigid and frequently flouted FAA rules, requiring use of supplemental oxygen only “whenever cabin altitude exceeds 10,000 feet for a period in excess of 30 minutes and whenever the cabin altitude exceeds 13,000 feet.”

HASO working group supporters include NBAA, the Flight Safety Foundation, GAMA, Bombardier, Gulfstream, Dassault Falcon Jet, Textron Aviation, AMAS and Airrowe.