I am looking for the HEPA Cartridges in vault 22 can not find any of them. Where do I need to go?

You need to go down to the 5th level, go outside into the caverns, and then go back into the OXygen Recycling room through the caverns, it lets you into an area that was blocked off previously. There's like 6 in a locker in there.

I went to level 5 and went into the cavern.

There is no usable ramp in the cavern other than the one you enter at.

There seems to be another tunnel, but you cannot reach it.

There are no other tunnels in the cavern.

http://www.youtube.com/watch?v=EtqWrsKwWt8

It's a little on the dark side, but easily followable... you're welcome.

You have to go down to the lowest level & find the entrance to the caves. Kill all the creatures, then there should be a rock down a ways on the same side you walked into the big open area in the caves, its a sloped down rock which you can walk up & get access to the section you need.

Thank you both CyricTheMad & Adcal.

Cyric - I had completely cleared the bunker, but never tried that Terminal to open the door.

None so Blind as those that think they have done it all.

Adcal - I still cant find the cavern option, so I am going to next Quest.

Thanks both