Technical Diving Courses
 

Staging the ascent
TDI Advanced Nitrox and Decompression Courses

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Does your No Decompression Limit (NDL) rather than your air supply bring you up from a dive?
Do you wish that you could stay down on that wreck a bit longer but find that your computer doesn't agree?
If that's the case, then it's time that you considered Nitrox.
For those of you that are not quite sure what that is and what it does, then have a look at the PADI Specialties page on the web site. In essence, it is a breathing gas that contains a percentage of oxygen greater than the standard 21%. As there is less nitrogen in the gas, your NDL is therefore greater which means you can stay down longer. Clever or what!? Just about every diver gets into Nitrox diving particularly those that dive regularly.

Having said that, there is only so long you can stay down on one tank of air. That's fine during a Red Sea trip where dive times are restricted to about 60 minutes, but what happens in the middle of the English Channel? We usually find ourselves diving on a wreck at 30mtrs or deeper where even on Nitrox, the NDL fast approaches. The deeper we go, the less oxygen we can have in our mix and we arrive at the NDL that much sooner. That's where Decompression diving comes in.

Most of you will have at least heard of decompression diving, coming up from the bottom in stages and stopping at various depths to get rid of the excess nitrogen in your system. Most of you probably think that this type of diving is only for 'Teckies' and you have to have more tanks than sense. Well think again. The art of 'deco diving' is to enable you to have the buoyancy skills and the ability to read a dive table in order for you to safely extend your dive past the NDL if you want to!

There you are at 35mtrs, on the wreck that has 12mtrs viz, and you're wearing a 15ltr tank and a pony bottle. Sound familiar? OK. You've been down a whole 12 minutes and your computer tells you that there is just two minutes until you reach your NDL but you still have 150 bar. Tough. You're coming up! Your pony bottle doesn't count 'cos that's only for emergencies. What if you could extend your bottom time on that dive by another 15 to 20 minutes and then just do a slightly longer safety stop of  8 minutes or so? Yeah? Now you're interested! For those of you that have already been out with us on club trips in the UK, you will have seen a lot of staff members spending a lot longer under the water than the other divers and that's after doing only 10 or 15 minutes decompression. Well you can do that too without the twin sets if that's what you want.

 

TDI Advanced Nitrox Course

This will allow the use of Nitrox mixes between 22 and 100% for dives not requiring staged decompression to a maximum depth of 40m. This course can be combined with the TDI Decompression Procedures course at the discretion of the instructor. Course manuals

 

You must be at least 15 years old unless this course is to be combined with the Decompression course in which case you will need to be at least 18 years old.

You must already hold a basic Nitrox qualification from a recognised training agency.

You must already have completed 25 logged open water dives.

It consists of one days classroom based Enriched Air theory followed by two days in open water.

 

TDI Decompression Procedure Course

This course will examine the theory, methods and procedures of planned decompression diving. It will teach you how to plan and dive staged decompression dives to a maximum depth of 45m. This course will show you the most common equipment set ups and configurations.The required decompression procedures are also presented.

You must be at least 18 years old.

You must show proof of at least 25 logged open water dives

You must have a qualification of at least Open Water Diver or equivelent.

The course requires one day in the classroom covering kit configuration and diving techniques, followed by two days in open water.

 

Combined TDI Advanced Nitrox and Decompression Procedure Course...

...Does exactly what it says on the tin. It combines the two courses into one but does not extend the time frame required for completion. Let's face it, if you're into Nitrox diving, particularly here in the UK, then it makes sense to combine it with deco' diving and vice versa. By combining the two courses at the same time, you obtain the optimum diving qualification and it still only takes three days. You can then do all the decompression Decompressingdiving you like (within safe limits!) and hugely reduce your stop times by utilising gas mixes up to 100% oxygen.

You must already hold a basic Nitrox qualification from a recognised training agency.

 

You must be at least 18 years old.

You must show proof of at least 25 logged open water dives

You must have a qualification of at least Open Water Diver or equivelent.

The course requires one day in the classroom covering Enriched Air theory, kit configuration and diving techniques, followed by two days in open water.