Subject: Emergency Oxygen Masks

From: [email-masked] (Gary Jacobs)
Date: Tue, 24 Nov 1992 07:43:50 GMT

Having just been involved in a flight where the oxygen masks
were dropped, I'm curious what the test criteria are and how
often is it done?  I'd also like to know what the failure rate
is?

On my flight, America West on a Boeing 737, an oil seal supposedly
failed on the APU for the air conditioning system.  This sent
oily smoke in the cabin.  I assume the cockpit crew decided that
breathing that air wasn't good for the passengers and dropped, or
should I say tried to drop, the emergency oxygen masks.  I'd say
that 1/4 of the overhead doors did not open until they were pried
open by a passenger and then a lot of the masks did not seem to
supply oxygen even after following the "pull hard to start the
flow of oxygen" instructions.  I looked at my mask which didn't 
work and could not tell what the "pull hard" did to start the
oxygen.

Gary Jacobs
[email-masked]

---

From: [email-masked] (goh kawai - n6uok)
Date: Wed, 25 Nov 1992 00:40:45 GMT

Gary Jacobs ([email-masked]) comments:

  | I'm curious what the test criteria [of oxygen masks] are and how often
  | is it done?  I'd also like to know what the failure rate is?

I was on a flight the other day (B-747) when an oxygen mask dropped by
accident in the business class cabin.  I was horrified to see that the
plastic tubing that connects the mask to the oxygen supply was
brownish-colored due to age.  I have an aquarium at home, and I know how
long it takes for air-tubing to turn brown.  While it is quite conceivable
that they use a higher grade of tubing in aircraft, that is not awfully
reassuring, because low-grade or high-grade, old tubing is old tubing.  I
shudder to think what condition the rest of the system is in.

-goh-

----------------- Speech Research Program, SRI, Menlo Park, CA 94025-3493 USA
--- Goh Kawai --- work:(415)859-2231   fax:(415)859-5984   home:(415)323-7214
----------------- internet: [email-masked]      radio: n6uok and jk1zyp