Cabin pressure issue - question about oxygen system and masks
 

We had a cabin pressurization issue on today’s LAX-SFO flight. Aside from the fact that many of the panels didn’t open to drop the masks (?!), I’m curious if anyone has insight into how the oxygen is circulated/how the system works.

Did I just directly suck down/share my fellow passengers’ breath along with the oxygen? Color me paranoid.

Thanks.

Most/all aircraft use this system:
https://en.wikipedia.org/wiki/Chemical_oxygen_generator
Your oxygen was generated for YOU and no-one else.

Correct. The reason you "pull on the mask to activate the flow of oxygen" is that this action starts the chemical reaction in the oxygen generator that produces the oxygen. Each generator will "burn" for about 15 minutes when activated. It can not be shut off.

The masks themselves will not drop until the cabin altitude is above 10,000'. A pressurization problem doesn't mean that the cabin altitude is already above 10,000'. It just means that there is a problem with the pressurization system. There's often time to stop climbing, or even descend, before the cabin altitude gets above 10,000'.

This is correct. the only DL aircraft that had an "oxygen tank" in recent years (instead of a chemical system) was the 747 if I recall correctly. even then the oxygen wasn't recirculated.

That can happen. FAs are trained to open the panels manually, but generally we wouldn't have the opportunity because before we even get to that point the aircraft is usually descended to a safe altitude. our the pilots are trained to descend rapidly, we take our seats or secure ourselves in place immediately at DL. some airlines are trained to monkey bar (move from mask to mask down the aisle) but we don't do that at DL.