Padi Wreck Diver manual

[Bubbletrubble]

The PADI Wreck Diver class presumes that the diver is not trained in [-]advanced[/-] decompression procedures and such training is not provided as part of the Wreck Diver curriculum. The guideline is a rule of thumb that encourages the diver to be relatively conservative in his wreck diving.

 

[Indian Valley Scuba]

Holy goshmoly, where did this morph into considerations for "advanced decompression"?

The question was simply one of depth, not time at that depth!

 

[Bubbletrubble]

Holy goshmoly, where did this morph into considerations for "advanced decompression"?

The question was simply one of depth, not time at that depth!

@Indian Valley Scuba: I removed the word "advanced" from my post above, if it makes any difference. Your comments imply a clear separation between decompression diving and diving conducted in overhead environments. I think decompression diving warrants discussion in a wreck diving course since that's what the diver may have to deal with if he gets stuck inside the wreck and exceeds his NDLs.

I think it's a shame that a diver can step through the PADI course progression, take the Wreck Diver course, and not have had any formal training in gas planning/management, let alone how to conduct decompression diving.

 

[Indian Valley Scuba]

I certainly respect your thought process and personal view on the educational system, but again, the initial question posed was simply one involving the magic number 130 ft. Hence my response.

 

[Gilldiver]

Back in the day, there was no 130’ rules, my copy of “The New Science of Skin and SCUBA Diving” from 1966 makes no mention of the 130’ rule but does have the Navy air tables down to 300 feet for 180 minutes (you get a 1,165 minute accent time for a total run time of 1,345 minutes).

The 130’ depth “limit” for recreational diving comes from the same US Navy Air dive tables used from the 1950’s up into the late 80’s/early 90’s. On these tables the no decompression times are:

100’ = 25 min
110’ = 20 min
120’ = 15 min
130’ = 10 min
140’ = 10 min
150’ = 5 min

These times are from when you leave the surface to when you leave the bottom. The Navy considered 10 minutes to be the minimum amount of time to do any useful work for a free swimming SCUBA diver (2-5 minutes for decent/5 to 8 minutes for work or inspection). Therefore, the US Navy limited SCUBA divers to a maximum depth of 130’ unless they had the standard surface support & controls required for US Navy diving. When the agencies started to get going in the late 60’s and early 70’s they just adopted the 130’ Navy rule as the recreational limit for non-professional divers.

 

[DevonDiver]

I understand that the rec depth limit is 130'. But I don't understand why there is a penatration limit imposed of 130' from surfacing. Is 130' just the distance someone has figured that a diver can swim while letting out a continueous stream of air?

Having restrictions on PADI wreck divers replicates the distinction between recreational cavern diving and technical cave diving.

The line has to be drawn somewhere. After all, the PADI wreck course is only an orientation course, not a technical penetration course.

You can't do a cheap 2 day, 4-dive course and then think you are effectively trained for operating in a high-risk overhead environment at the outer limits of recreational diving depth?!?

PADI Wreck Diver Certification

- Doesn't assume that the diver concerned is trained to use 'rule of thirds' or will be diving according to a precise gas plan, using independent manifold doubles.

- Doesn't assume that the diver concerned is trained in effective line laying skills, or has been trained in line contingency drills or zero-viz skills.

- Doesn't assume that the diver concerned is equipped and trained to complete emergency decompression.

Reasons for limiting depth/penetration for PADI Wreck divers

1) 130' represents the maximum distance from the surface that PADI feel is safe for CESA (OOA emergency ascent).

2) The distance of penetration is proportional to the shorter NDL available at depth. For example, at 100' there is 20 minutes NDL. For a 30' penetration at this depth, there is 10 minutes down and in..and 10 minutes out, before ascent. This is about right for proper penetration, with line, and to allow a few minutes contingency to prevent NDLs being exceeded.

3) The distance of penetration is proportional to the shorter air-time at depth. Increased rate of air consumption at depth means that penetration into an overhead environment should be proportionally limited. Even where a diver may have sufficient air, there is need to account for contingency factors; especially any accelerated RMV issues involved with potential emergency/stress.

Limitations

I agree completely that recreational wreck divers, whose training does not exceed the PADI Wreck Diver orientation course, should be subject to severe limitations in wreck penetration. The PADI Wreck Diver course isn't a penetration course... and does not teach any of the skills required for safe and effective wreck penetration.

Quite frankly, I think that the limitations of PADI wreck divers are not clearly defined enough (compared to say, PADI Cavern divers).

For those that disagree with the limitations - take an advanced wreck (penetration) course and see if your mindset changes. I pretty much guarantee that it will

 

[BoltSnap]

For those that disagree with the limitations - take an advanced wreck (penetration) course and see if your mindset changes. I pretty much guarantee that it will

Does PADI have an "advanced wreck (penetration) course" or is this something that would be done through another agency?

 

[Rhone Man]

Does PADI have an "advanced wreck (penetration) course" or is this something that would be done through another agency?

I don't think it is one of their "standard" specialties, but I have seen a number of different LDSs offer a course named exactly that as a 'distinctive' specialty.

 

[DevonDiver]

Does PADI have an "advanced wreck (penetration) course" or is this something that would be done through another agency?

No, they don't.

A number of individual instructors have submitted 'distinctive specialities' for technical/advanced wreck. I've written one also, but was holding off because of an on-going rumour that the DSAT program was going to include one (a rumour that has persisted since at least 2007).

I had drafted a recreational diving version, but it would require a level of pre-knowledge (doubles, air-sharing long hose, gas planning etc) that kind of makes an entry-level tech qualification a very reasonable pre-requisite...

 

[jar546]

I am just surprised that PADI is advocating penetration at all at the basic, recreational wreck diving level.