For some mid-winter-storm entertainment, and also because it was overdue, I felt I should test the lifejacket.  You should get your lifejacket serviced at the intervals recommended by the manufacturer, but there’s no reason not to test it yourself as often as you can.  It only needs one flaw to let you down.

The process is more or less like this:

1. Unpack and inflate.  You can do this with your mouth, as the flight attendant has probably told you numerous times.  It’s easier than you might think, but has the disadvantage that some moisture will get inside the chamber.  I used this:

.. which took much longer!  But did the trick.  There are likely better pumps for the job.

2. Leave overnight and check the pressure.  It should be as solid as when you left it:

Deflate it with the little black cap that covers the mouthpiece.  Don’t jam random implements into the valve – it’s an important part of your lifejacket.

3. Examine webbing, buckles, velcro and chambers for signs of fraying or wear.

4. Check the trigger is in date, hasn’t been set off (look for green and green as in the picture) and check the gas bottle isn’t corroded.  You can replace these parts yourself if required.

5. Screw the bottle back in fully, then repack the inflatable chamber carefully (and correctly).

What if the inflatable chamber didn’t hold its pressure?
Throw it away and buy a new lifejacket.  It’s not economical to repair, and no one would guarantee a repair anyhow.