Deep diving class - equipment requirement.

[ClayJar]

I have dove to 90 to 93 ft several times in warm weather. It doesn't seem like going to 100 ft would be much different[...]

The process of diving does not dramatically change between 90 and 100 feet. There is increased potential for narcosis; your air consumption increases (not necessarily your SAC; the actual quantity of your tank's air per minute); etc.

The deeper you dive, the more critical everything becomes. The details of gas planning become significant, as does paying attention to your instruments. Things have a much greater tendency to cascade at depth. If you don't watch your depth on a deep wall, for example, you can easily find yourself narced, using gas at an accelerated rate, and under a deco obligation. An apparently common reaction I've seen to more advanced classes is to be stunned that you would have ever done some of the dives you'd done before learning about what could go wrong, how to handle it, and how to prevent it.

When I hear of people right out of OW going on deep dives with no understanding of what can go wrong, I cringe. A good deep diving class should at the very least make you *think* more conservatively. Sure, a deep diving class will let you experience diving deeper, but if you get to the deep dives and you're diving the same gear the same way with the same considerations, you've gained all but nothing.

 

[muddiver]

If you have the money to spend, then yes get a pony with a seporate regulator. The point that everyone on this board glosses over is that a pony is a totally redundant source of air for you. I have been diving both a Sherwood Brut and a Sherwood Blizzard for years and I have never had any serious problems with them. They usually work great all the way to 135 feet.

If you go the pony bottle route remember one thing. Remove the octopus from your primary regulator so that you do not have a third regulator on you. It is very easy to mistake the second regulator coming off of your main tank for the regulator coming from the pony. There was another post on this last week where a basic open water trained diver in a training class had an issue with grabbing the third regulator which was attached to a tank his instructor had shut off at depth.

how you set your pony up is your business. I hang mine up-side down on my main tank so I can reach down with my right hand and grab the valve on it. That is how I have drilled for years to react in an out of air emergency as a commercial diver wearing a full size tank as a back up. I also leave it turned off because I don't want it bleeding down during my dive. The hose and the second stage are pressurized from checking to see it the pony is full before I hit the water, then I turn it off.

Sorry for the long story, it's just my $ 0.02

 

[ClayJar]

If you go the pony bottle route remember one thing. Remove the octopus from your primary regulator so that you do not have a third regulator on you. It is very easy to mistake the second regulator coming off of your main tank for the regulator coming from the pony.

As I dive with my pony slung on my left front side (shoulder to hip) with the hoses bungeed to it, the pony reg will not be mistaken for anything. For reasons which were discussed (at *excruciating* length) in another thread, I categorically *refuse* to remove my "octo", but you're commenting on a completely different gear configuration.

If you dive a pony, regardless of the config, dive it often enough that you can switch to it blind and upside-down during an unexpected free-flow. Unfamiliarity breeds accidents, and only by being intimately familiar with your gear are you going to be able to handle it when the need suddenly arises.

 

[tedwhiteva]

Cold water free flow - usually first stage starting to freeze up, over-presurizing the intermediate pressure to the 2nd stage, which is designed to free flow vs. a bursting the LP hose.