RAF Oxygen Regulator question

[DragonflyDH90]

OK, this may or may not be the right place to post this but couldn't think were else to put it.

Anyone ex S&S or equivalent, maybe Dave may know this also as I'm not sure whether these were ever RNZAF issue.

I have in my possession a chest mounted 317a oxygen regulator. I am trying to figure out its exact workings as I am just fitting it up to a bottle system for portable use but some literature or inside knowledge would be great.

I understand the general operation in that it has a lever for switching between 100% O2 and O2/air mix but there is a secondary two position knob which I presume is switching between demand and pressure feed for very high altitude ops. I'm after confirmation on this and an indication of what position is which as it isn't labelled.

Not after speculation so if you're just taking a stab in the dark it's probably no more info than I currently have but if you are a little more in the know that would be great.

[camtech]

Normally, oxygen regulators were serviced by Instrument/Avionics trade, but that model is unknown to me.
Quite possible the secondary knob is as you suggest, but would need to find something more definitive.

Edit - could also be a normal/emergency selector.

[Dave Homewood]

The only time I ever touched O2 masks was on my Safety Equipment course in 1991 for a very brief overview, most of which I have long forgotten. The Safety and Surface workers who had hands on with them were guys attached to the operational squadrons, which I never was (I was always in Maintenance Squadron or Wing units).

[DragonflyDH90]

Thanks for that guys. Hopefully someone might be RAF in that trade who can help.

This is what it looks like

[lesterpk]

I've asked on a flying clothing nerd email list I'm on to see if anyone has a manual for it, if there is one about these guys will have it.
I'll let you know how I get on.

[lesterpk]

One of the list members is pretty sure he has a copy of the manual, but he's not at home at the moment. Might be a week or two before he is.

[DragonflyDH90]

Thanks very much. Keep hounding him if that is OK.

I have found that it was manufactured by NGL in the UK which has since been taken over by Honeywell. I have one of their senior techs chasing down some info if its still around but I would certainly appreciate anything else.

Happy to wait a week or two if that's what it takes.

Cheers

[martytheduck]

Is that my one?