Or are people who said that confused by this
"from FAR 121.327
(1) For flights of more than 30 minutes duration at cabin pressure altitudes above 8,000 feet up to and including 14,000 feet, enough oxygen for 30 minutes for 10 percent of the passengers."
(e)Passenger cabin occupants. When the airplane is operating at flight altitudes above 10,000 feet, the following supply of oxygen must be provided for the use of passenger cabin occupants:
(1) When an airplane certificated to operate at flight altitudes up to and including flight level 250, can at any point along the route to be flown, descend safely to a flight altitude of 14,000 feet or less within four minutes, oxygen must be available at the rate prescribed by this part for a 30-minute period for at least 10 percent of the passenger cabin occupants.
Also as if I didn't already ask enough...
Does this mean that the PAX must be able to see their oxygen flow indicator?(c) The equipment required by this section must have a means -
(1) To enable the pilots to readily determine, in flight, the amount of oxygen available in each source of supply and whether the oxygen is being delivered to the dispensing units; or
(2) In the case of individual dispensing units, to enable each user to make those determinations with respect to that person's oxygen supply and delivery; and
(3) To allow the pilots to use undiluted oxygen at their discretion at altitudes above 25,000 feet MSL.
I'm not too familiar with aerospace, FARS, or any aircraft regulations, but is that the type of thing that would be listed in a FAR? - how many PAX oxygen masks for a commercial twin-aisle aircraft, or is that left to the discretion of an airliner. Also is this a good place to discuss FARS, or is there a different forum for this? I have more questions about regulations on different topics (and no one to go to that knows about them)