Max Depths

Hi Group

Mogwai and I were talking and had a question regarding Max Depths.

For us divers what is the actual Max Depth with proper training? I know was reading a book on Wreck Diving and a group done on the USS Monitor off of NC's coast and it sits in roughly 250 feet of water. So what is the max depth if we did the proper training just curious I had heard somewhere around 400 but unsure.

Also what is max depth in the old upside down glass style brass helmets? As some of you may have heard someone is attempting to raise money by walking across Loch Ness in Scotland

Ness diver hits loch bottom as he sets himself monster task

And was just wondering how deep he could go being he's breathing surface air and if this makes a difference over compressed tank air. I do know I watched the movie Men of Honor which is based on a real life story and supposedly the Master Cheif character did get decompressed in such a suit if I remember the story right but just curious how deep you could go in a suit like this as well as some of the depths in Loch Ness get as deep as 745 Feet maybe even deeper now as that was recorded in 91.

What a great idea for a charity event! I don't know what the max depths for a suit like that are but I recently took my boyfriend on a trip where he could try that system out in a harbour. He and his friends only went to about 2/3 metres and I tell you pumping the air from the surface to them was no easy task once they got below about 1.5 metres! So if the guys in the boat are pumping the air by hand as we were then I guess that will be the deciding factor as to how deep he could go.

As to your other queries I 'm afraid I have no idea. Sorry.

scottish2 once bubbled...
Hi Group

Mogwai and I were talking and had a question regarding Max Depths.

For us divers what is the actual Max Depth with proper training? I know was reading a book on Wreck Diving and a group done on the USS Monitor off of NC's coast and it sits in roughly 250 feet of water. So what is the max depth if we did the proper training just curious I had heard somewhere around 400 but unsure.

Also what is max depth in the old upside down glass style brass helmets? As some of you may have heard someone is attempting to raise money by walking across Loch Ness in Scotland

Ness diver hits loch bottom as he sets himself monster task

And was just wondering how deep he could go being he's breathing surface air and if this makes a difference over compressed tank air. I do know I watched the movie Men of Honor which is based on a real life story and supposedly the Master Cheif character did get decompressed in such a suit if I remember the story right but just curious how deep you could go in a suit like this as well as some of the depths in Loch Ness get as deep as 745 Feet maybe even deeper now as that was recorded in 91.

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Hi Scottish,

As I recall, the maximum depth ever reached on scuba is about 300 metres (note metres, not feet) by a guy from teh UK called John Bennett or something-like-that. A couple of other howling kamikaze's are trying to better that record to 333 metres in Egypt this year (their original plan was 350 but they've brought it back to 333). The limit to deep diving with scuba seems to be the amount of gas you can take with you for proper decompression.

Surface support diving is another matter. 300 metre dives are common among commercial divers and even deeper dives have been done. I don't know what the record is but I know of at least one dive to something like 2300ft (whatever that is in metres)

R..

Wow that's a lot more then I expected. Would hate to sit through the decompression on that trip. I know was just checking my book and I made a slight mistake the wreck lays in about 230 feet not 250 feet but they said for 18 minutes BT they have to sit over 100 minutes decompressing. WOuld hate to see it from over 900 feet as 300 metres = roughly 985 feet and to answer your question on the 2300 that would be roughly 701 metres.

scottish2 once bubbled...
Wow that's a lot more then I expected. Would hate to sit through the decompression on that trip. I know was just checking my book and I made a slight mistake the wreck lays in about 230 feet not 250 feet but they said for 18 minutes BT they have to sit over 100 minutes decompressing. WOuld hate to see it from over 900 feet as 300 metres = roughly 985 feet and to answer your question on the 2300 that would be roughly 701 metres.

Click to expand...

The decompression required for a 20 minute 250 ft dive is nowhere near that when using the right gasses for decompression. Dives like that are done every day (with the right training and experience of course)

Well this book was written in 95 and that dive was probably even older then that so unsure how new this new mixtures are that would cut down decom times.

By the way has anyone heard of this pill the navy was supposedly trying to either devolope or was testing that cuts out having to make decom stops? My instructor mentioned something on this back in 98 but that was the first and last I heard of this pill.

For surface supplied diving the depth limitation (as far as equipment goes) is dependant on the supply air pressure and flow...

The helmet itself is going to be equalized with the depth the diver is at so there really is not any external pressure on the hat...

The early "compressors" like Phish-phood (my favorite ice cream by the way!!) is describing used from the early 1800's through the 1940's as the primary air source for surface supplied diving. Some folks are still using it during historical diving demonstrations or "working equipment group" dives...

These compressor pistons were gasketed with leather that would have to remaing moist to ensure a seal, the divers surface tenders would crank away on the unit while monitoring a pressure gauge to ensure the diver had enough air. The helmets had no demand system installed and the diver could control air flow with both an inlet valve and an exhaust valve, these were also used to fluxuate the diver buoyancy...

Later units encorperated a volume tank allowing the tenders to take short breaks or to stop and lubricate the system.

These early compressors were capable of sustained diving to around 100 feet sea water.

With the development of high pressure compressors and air regulating systems divers were able to reach ever increasing depths. It has been stated many times that divers had reached the limits of depth but that continues to be pushed further as time goes on.

A French company called COMAX In 1992, took divers to a depth of 675 meters after 18 days of compression. They were breathing hydro-heliox. One of the 3 divers stepped over into a smaller tank and went down further to 701 meters.

This si the deepest confirmed depth I know of...

Jeff Lane

I take it that 701 is the same one that mentioned above? So this was helmeted?

I take it that 701 is the same one that mentioned above? So this was helmeted?

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It is the same "dive" but was a hyperbaric - shore dive, Comex also holds the record for the deepest open water dive "Hydra 8"

Jeff Lane

scottish2 once bubbled...
Hi Group


Also what is max depth in the old upside down glass style brass helmets? As some of you may have heard someone is attempting to raise money by walking across Loch Ness in Scotland

Ness diver hits loch bottom as he sets himself monster task

And was just wondering how deep he could go being he's breathing surface air and if this makes a difference over compressed tank air. I do know I watched the movie Men of Honor which is based on a real life story and supposedly the Master Cheif character did get decompressed in such a suit if I remember the story right but just curious how deep you could go in a suit like this as well as some of the depths in Loch Ness get as deep as 745 Feet maybe even deeper now as that was recorded in 91.

Click to expand...

The article you linked to says the depth he will go to is nearly 10 metres, which is just a bit under 33 ft.

A different article I read recently talked about the diver walking around, not across...

Sean