About: http://webisa.webdatacommons.org/55375841

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	When that occurs at high altitudes such as above 30,000 feet, pilots have a short period of time to don an oxygen mask before slipping into unconsciousness.
http://www.w3.org/ns/prov#wasQuotedFrom	catallaxyfiles.com