"pbc76049" wrote in message
...
Most passenger O2 systems use chemically generated O2.
There are no bottles to check. There are cabin walk around bottles
and the flight deck is bottled O2, but passengers are not. Remember
the Valujet crash. The initiating event was a cargo bay/cabin fire casued
by
improperly shipped O2 generators igniting in flight.


Even if the passengers have chemically generated O2, the pilots have O2 from
a bottle. Pilots are required (and most do) check their O2 before take-off.
The chemically generated O2 units cannot be turned off once in use and then
must be replaced. Therefore pilot positions have bottled O2.

Duane