1 ATM containers

[JohnnyH]

Yesterday I was asked an interesting question that I thought I'd relay to this forum.

Does anyone know of any manufacturers of 1 ATM watertight containers that are rated for use down to 4 or 5 ATM?

In specific, a container to hold items like a VHF radio and keep it at surface pressure - basically similar to a camera housing, or similar to but smaller than the containers used to deliver goods to NOAA's Aquarius habitat - though without the requirement of venting gas when travelling from a higher pressure to a lower one (such as when items are transported from the Aquarius to the surface).

Any assistance appreciated.

John

 

[Sharky1948]

I wonder what the pressure rating on a Pelican case is???? My guess is that 4 to 5 ATA might be a bit much...


Could be a fun in-water experiment though!

 

[sbrooks]

I looked on Pelican's website - it didn't say anything about depth ratings/pressure capacities. Would they be what you're looking for? http://www.pelicanproducts.ca/industries/Dive.htm

 

[kidspot]

Most of the pelican cases I've seen were rated to 6fsw I think. You might check Otter boxes - they are rated to 130fsw, but not vented, so you'd have to find a way of putting an overpressure valve in yourself.

 

[Sharky1948]

If I understand the OP correctly, there would be no need to an OPV. If the box is to be opened in a 1 ATA environment, all should be well.

Interesting that Otter builds for depth.

 

[kidspot]

my missunderstanding - I thought he needed to put things in it while at depth (the whole aquarius reference) and open at the surface.

Still otter boxes are probably the least expensive option - thought they are not double oring sealed.

 

[JohnnyH]

If I understand the OP correctly, there would be no need to an OPV. If the box is to be opened in a 1 ATA environment, all should be well.

Interesting that Otter builds for depth.

I had checked out Pelican but they didn't meet the depth requirement. I had found other manufacturers but none that were depth rated. I hadn't come across OtterBox, so thanks for the suggestion - that might just fit the bill.

Only question would be about getting neutral - looks like they are ABS plastic which I believe is pretty buoyant - on top of the volume of air inside.

Regardless - thanks for the info.

[EDIT: Oh and yes - no need for a purge as the internal pressure will always be 1 ATM (or whatever the surface pressure is) ]

John

 

[fdog]

I'm assuming you want to take your VHF radio diving with you so you can use it to holler for help if the boat leaves you or something.

There's a couple of options that are reliable enough for me:

>Get a custom canister from Sartek. Depth rated and very reliable.
>Ikelite makes square utility housings from clear polycarbonate. Quite durable and you can see through it, a nice thing.
>If you radio fits, Pains-Wessex makes a metal dive canister for their FastFind PLB.

Otter Boxes are sold as tested to 100 feet, but for me, I would look at this as yield pressure, and not as working pressure. It's not something I would care to place a piece of life safety equipment into, but may be right for you.

All the best, James

 

[roakey]

Many time dive light cannisters, minus the dive light, are used for the tasks you're asking about. Something like this minus the hole for the light cord:

http://www.sarind.com/acatalog/cbpl9li.JPG

Roak

 

[roakey]

If I understand the OP correctly, there would be no need to an OPV. If the box is to be opened in a 1 ATA environment, all should be well.

What's 1 ATA?

Side story: I live at almost 8,000 feet. I flew to sea level with my Nikonos years ago and spent about an hour trying to get it open!

Roak