30m - deep?

[Leg Of Salmon]

I am considering buying twin sevens this summer for improved redundancy. Its a better option than a pony in my opinion. All my diving will be 0 to 35m. Would be grateful for any input.

[NotDeadYet]

I started freediving a few years ago and when you've worked your way up to the 30m zone then you suddenly realise just how far down it is and just how exposed you are. 30m up on one breath is a very long way, it gave me a new found respect for depth.

Originally Posted by Clare Gledhill

I've always seen depth is pretty irrelevant once you have factored for gas. Time to the surface is what makes a dive serious to me - whether that is deco or exit time.

It's just a semantics issue. "Deep" is a nice catch all which indicates the rough crossover point where quickly increasing time to surface is balanced with quickly decreasing available gas.

I've been cave diving for about 10yrs and mix diving for about five years beyond that, I don't see depth as irrelevant, it strikes me as a rather naive statement. It's only irrelevant when things are going well. Have a rebreather failure at depth (and/or distance) underground, possibly combining with a CO2 problem and you will quickly see that depth is extremely relevant in cave diving. A wagon of gas is no reassurance when a major incident has happened, especially if carbon dioxide is involved. Trust me, I've been there and it's been the biggest eye opener I've had underwater. Rebreathers are a major step forward in safety at depth but they also introduce the single most dangerous problem you'll face underwater, underestimating it is a one way ticket.

Cheers,

Stuart

[scuba g]

Originally Posted by Leg Of Salmon

I am considering buying twin sevens this summer for improved redundancy. Its a better option than a pony in my opinion. All my diving will be 0 to 35m. Would be grateful for any input.

Unless they are 300bar, then its false economy, twins are definitly better for stability than a pony, but the capacity needs to allow you redundancy that includes gas down, gas back to the surface and a reserve of gas that allows for f**kups, the rule of thirds, so if you look at what you would consume on a dive to 35m and back, and calculate a margin for error, then thats the capacity to go for, IMO

[scuba g]

Originally Posted by Clare Gledhill

I've always seen depth is pretty irrelevant once you have factored for gas.

Diving in 20m's compaired to diving in 60m's is relevant in my opinion, apart from gas considerations which I agree with, other factors add to it, what gas you are on (air/trimix), the conditions you are in, warm water/cold water, good or bad viz, these all affect the divers perception and with physical factors also affecting the diver, then its important. If I was diving on my RB to 40m's and on OC to the same, it feels very different, one is the gas mix but also tasks you do while on the dive.

My tupence worth on the matter

[Mark Chase]

Originally Posted by liamm

As much as comfort zones can be misleading, being over cautions or misseadind risk can be misleading.

I dont think depth is the issue at all, if the dive is planned for and the gas is apprpriate with enough bailout or redundancy.

In some ways i feel that a 40m dive taken seriously is much safer than a 15m bimble done casually. I see loads of these types of dives - no redundancy (buddy / team or otherwise) and no thought to time planing. You can do a bouyant ascent much easier from 15m but i dont think that makes it safer.

i'd rather plan not to run out of gas, or as in Si's post yesterday have a team nearby to donate gas in case of equipement failure.

This is a very good point. A lot of CCR divers have died in less than 20m of water and I beleive (but its just a beleife) its because they couldent mentaly take the dive seriously.

This is farr less an issue on OC but its still a good point. We dont necessarily prepair for w perceived shalow dive in the same way we do for a perceived deep dive.

ATB

Mark

[Buoyant Babe]

Is it not that there is is a big difference between what is 'deep' and what is 'risky' to an individual?

I still think 30m is deep, but as my level of diving has progressed it is of less a risk for me to dive because I try to plan for it.

For a recently qualified diver with few dives, no back-up gas and limited (if any) SMB deployment skills its a BIG risk.

As I think someone else has pointed out, it's about your comfort zone.

[chrisch]

Originally Posted by Leg Of Salmon

I am considering buying twin sevens this summer for improved redundancy. Its a better option than a pony in my opinion. All my diving will be 0 to 35m. Would be grateful for any input.

I think its a good choice. You might want a bit more gas as you develop and so move to bigger twins, but you will have had a great chance to practice valve drills and get your configuration right. I wish I had done that instead of starting twinset diving on 12s.

Chris

[Waskey]

The way I look at it is that every dive to whatever depth should be planned. If you've done a lot of dives and you have enough experience that the plan is a 'standard dive' then that's ok. I know on a 35m dive when I spend 25mins at depth, I roughly have about 9mins of stops if I'm decoing on air and I have more than enough gas. Therefore 30m isn't exactly a big deal for me.

But shallow and deep adds complacency. You look at some stories of deep divers ballsing up on relatively 'shallow' dives because they took the dive for granted. You should dive a dive to 10m with the same care as you do to 50m in my opinion.

[SoggyFox]

Originally Posted by Buoyant Babe

I still think 30m is deep.

its deep when your there its even deeper when you don't want to be.

[Buoyant Babe]

Originally Posted by SoggyFox

its deep when your there its even deeper when you don't want to be.

Huh? Sogs you lost me!