According to the article “When a senior Navy pilot showed photos of a faulty oxygen system” What does a faulty Oxygen system look like? Doesn’t paste the sniff test. By the way all that has to be done is for the unit(s) is to request an Engineering Investigation (EI). Three incidents have been reported for CY 2017.
The system does not detect contaminants.
The article says multiple pilots have passed out. It also says there are other incidents where the pilots did not pass not but had trouble flying because of the hypoxia.
I am not sure how contaminants are getting into the oxygen system, but these are very old jets.
A few years back, F-14's started having stress fractures that I believe grounded some of the F-14's (or all) until this could be checked out.