Deco + safety stops?

[td275]

I’m in the same boat as others who ‘plan the dive and dive the plan’. Every dive for me is a deco dive. Rec or tech, 30 ft or 300, I WILL BE decompressing as I come up. My GF is 50/80. I like that because my plan allows for shallow stops. Combined with how I ascend I can clear stops quickly. However I put the GF% and SurGF displayed on my computer so I can use it as a speedometer. As I ascend if I can keep my GF% at 40+ that will help “burn off” my SufGF faster. Additionally no matter the dive depth the last 20 ft I will slowly crawl up. Keeping the GF% at 40+ and getting my SurGF down to 72 before I surface. Although my computer is set to 80, and I am comfortable with that I have noticed my head will feel amazing if I can get my SurGF at 72 or below before I surface. My head feels even more amazing if I am on deco gas of 100%.

 

[grassybreakfast]

And practice. Lots of practice.

Even in a shallow 10m/33ft lake (near Heathrow ) you can practice decompression ascents. Just do stops every metre/3ft. Platforms have their uses too as you can do some skills & drills whilst hovering a couple of feet from the edge (some lakes have crap visibility!). If you can hold that position for 10 minutes using the platform as a reference, you're well on the way to good decompression skills.

Caveat: the sea doesn't have still water nor conveniently located 6m/20ft platforms! Your main reference is your SMB reel/spool bouncing up and down in the waves.

Yes of course . More training (formal and informal) and practice is always on the cards. I haven't had trouble holding arbitrary depths in relatively calm water, but don't have experience in very choppy water.

Have done plenty of dives in that lake back in the days .

I think what you laid out above takes “light deco dabbler” to a new level.

While I recognize value in your confidence, I don’t think it has the right underpinning. You’re rationalizing matters rather than deviating from a position of competency with technical knowledge and skills.

I encourage you to get more training.

I am absolutely not coming from a position of already having great skills and experience. As mentioned in the OP, I am only just starting to do my research and looking into it (despite technically already having a card that allows me to do it - obviously having a card or not does not reflect skill). I just like to ask questions and learn more things. If I'm wrong, and I often am, I would much prefer being proven wrong through rational discussion rather than appeal to authority (or lack thereof in this case).

 

[steinbil]

Are these people trained for back gas deco? I feel like maybe introducing deco earlier in training would help with this kind of situation.

I disagree. I think introducing deco at an earlier point in training will lead to divers underestimating the added risk and complexity of having mandatory stops and a virtual ceiling, and dabble with light deco without getting further technical training. You are actually living proof - you were introduced to deco at an earlier stage and the way you are talking about it seems to underestimate it, in my opinion and that of a few others in this thread. I don't mean this as any sort of slight, it seems like you are trying to be cautious and I appreciate that you are looking to challenge your perception by starting and participating in this discussion, but it is a data point that correlates with my perception.

Many people would like to be able to spend say 10 minutes at a 35m wreck but don't want to go any further. Do they really need several tech courses and spend thousands of $/£/€ to be able to do that? It's really not that difficult to plan for short back gas deco. Guesstimate emergency SAC rate, decide on a max TTS (say 10 min), calculate min gas, and have a plan for loss of gas. Then NDL+10min is the new limit. 10 min not enough? Just plan for a longer limit instead (assuming sufficient gas).

The only bit that requires significant training is redundant gas, if required. That would depend on individual risk profile.

I'm not going to pretend to be any sort of expert, I recently finished the first level of technical training myself. However, I would say that I learned a lot more than what you are describing. Not only in terms of skill refinement to be able to proficiently control ascent speeds, hovering midwater while keeping track of depth/time/gas and references (if any), and teammates, while executing different tasks - but also problem solving skills and procedures to deal with failures when going to the surface involves a significant risk of injury. Any kind of deco obligation without redundant gas, is crazy talk in my opinion.

I am absolutely not coming from a position of already having great skills and experience. As mentioned in the OP, I am only just starting to do my research and looking into it (despite technically already having a card that allows me to do it - obviously having a card or not does not reflect skill). I just like to ask questions and learn more things. If I'm wrong, and I often am, I would much prefer being proven wrong through rational discussion rather than appeal to authority (or lack thereof in this case).

I don't think this is an area where you will be proven wrong, especially in a theoretical discussion on a forum like this. Maybe taking a tech class with a good instructor would prove you wrong, in terms of showing you what you don't yet know and getting honest feedback about what you need in terms of skill, knowledge and respect for limits in order to start undertaking technical dives. Of course, risk tolerance plays a big part, but if you don't have the training and experience it's very hard to get a feel for the actual risk and consequences of the type of dives you want to do - hence the appeal to authority: When you don't know what you don't know, all you can do is listen to people with more experience, or go your own way and risk not learning from the mistakes of those that went before you...

 

[grassybreakfast]

I'm not going to pretend to be any sort of expert, I recently finished the first level of technical training myself. However, I would say that I learned a lot more than what you are describing. Not only in terms of skill refinement to be able to proficiently control ascent speeds, hovering midwater while keeping track of depth/time/gas and references (if any), and teammates, while executing different tasks - but also problem solving skills and procedures to deal with failures when going to the surface involves a significant risk of injury. Any kind of deco obligation without redundant gas, is crazy talk in my opinion.

Yes, that is true. I have only been talking about the dive planning aspect of it. The physical skills aspect of it is obviously also very important, and that is why I am also seeking out further training, and won't be actually doing deco dives until I get comfortable with a redundant gas setup including managing emergencies, and when I first start doing it, it will be with people much more experienced than me.

Maybe the club environment is also more conducive to more relaxed cert limitations and relying on people's best judgement, because often there are very experienced mentors around that can give good advice, and it's not a case of once you have the card, you are on your own.

And I am sure tech training covers way more than that. Otherwise people wouldn't be spending all that money and time doing tech courses. The question was, for someone who just wants to do 10min at 35m, does it make sense to require an intro to tech + DP courses? I don't have an answer, it's just what I am wondering. That's why it's posited as a question, and it's not a rhetorical question. Whatever I think at this point (I've learned to not share that now!), I may very well completely change my opinion once I've undertaken more training.

I don't think this is an area where you will be proven wrong, especially in a theoretical discussion on a forum like this. Maybe taking a tech class with a good instructor would prove you wrong, in terms of showing you what you don't yet know and getting honest feedback about what you need in terms of skill, knowledge and respect for limits in order to start undertaking technical dives. Of course, risk tolerance plays a big part, but if you don't have the training and experience it's very hard to get a feel for the actual risk and consequences of the type of dives you want to do - hence the appeal to authority: When you don't know what you don't know, all you can do is listen to people with more experience, or go your own way and risk not learning from the mistakes of those that went before you...

Yes, that is definitely possible, and I have much more training planned. I still don't think appeal to authority is necessary in this case. If I don't know what I don't know, I can be told what I don't know, and quite a few people have been helpful in that respect in this thread.

 

[steinbil]

The physical skills aspect of it is obviously also very important, and that is why I am also seeking out further training, and won't be actually doing deco dives until I get comfortable with a redundant gas setup including managing emergencies, and when I first start doing it, it will be with people much more experienced than me.

Sounds like a good plan!

Maybe the club environment is also more conducive to more relaxed cert limitations and relying on people's best judgement, because often there are very experienced mentors around that can give good advice, and it's not a case of once you have the card, you are on your own.

Yes. I'm also from a club environment, but one where the training is separated from the clubs. Although there are many advantages of the club diving in terms of learning from peers and divers with more experience, I would caution you that there are many in these kinds of environments that encourage people to dive outside of their limits or skill level, without actually taking a mentor role and making sure they don't get into trouble, and from my experience there is an element of normalization of deviance in these environments.

The question was, for someone who just wants to do 10min at 35m, does it make sense to require an intro to tech + DP courses?

The answer is that you can dive to 35m for 10 minutes without doing deco stops. You should however not rocket to the surface, as in any dive, really.

Whatever I think at this point (I've learned to not share that now!)

I don't think you should take it that way. The people that disagree with you, and possibly in a pointed way, are probably just trying to (a) dissuade you from doing something they think is reckless and/or (b) making sure a thread like this doesn't encourage untrained divers to do any kind of deco (no matter how light).

If I don't know what I don't know, I can be told what I don't know

I think this is a fallacy. Not everything can be understood intellectually. Not everything can be transferred aurally. I'm a professional dancer and a dance teacher, and I've come across many students that want to learn how to dance with their intellect rather than their bodies. I think there is something similar with diving - both in terms of physical and motor skills, and in terms of mentality/psychology - that can't be taught in a classroom or learned from a book.

 

[Alekseolsen]

The question was, for someone who just wants to do 10min at 35m, does it make sense to require an intro to tech + DP courses?

I feel you and Steinbil would be on "each side of the Valley. Steinbil woth GUE approach - which I must point out, I don't think is wrong, and you form a more relaxed CMAS/BSAC approach.

To answer the specific question, I'm quite sure AN/DP can be had without intro to tech - I know Advanced Recreational Trimix can be done without intro. Both would allow limited deco (perhaps not backgas deco for rec trimix, but you get to calculate either way) without adding a lot. Both are quite straight forward courses as long as you're squared away. (Doubles shutdown, buoyancy, No gas/no mask swims from memory). Iandt may still do the Kit-removal excercise.

My point is it's a 4 dive course which shouldn't require practice if you are in a position to do deco-dives already

 

[tursiops]

I'm a professional dancer and a dance teacher, and I've come across many students that want to learn how to dance with their intellect rather than their bodies. I think there is something similar with diving - both in terms of physical and motor skills, and in terms of mentality/psychology - that can't be taught in a classroom or learned from a book.

I agree with this 100%. I too teach dancing (Scottish Country Dancing) and there are many who think they can just "understand it" and thus be able to "do it."

 

[Wibble]

Just a plug for good core skills: buoyancy, trim, finning (including frog, helicopter turns and backfinning). Perfect those and diving becomes so much easier, especially when task loaded.

 

[grassybreakfast]

Sounds like a good plan!


Yes. I'm also from a club environment, but one where the training is separated from the clubs. Although there are many advantages of the club diving in terms of learning from peers and divers with more experience, I would caution you that there are many in these kinds of environments that encourage people to dive outside of their limits or skill level, without actually taking a mentor role and making sure they don't get into trouble, and from my experience there is an element of normalization of deviance in these environments.

That's interesting. In my case the experienced people are all instructors, and they do seem to be very safety-conscious.

The answer is that you can dive to 35m for 10 minutes without doing deco stops. You should however not rocket to the surface, as in any dive, really.

Ah yes of course, with the appropriate GF settings . What I meant is really anything within "recreational depth" that results in short deco at the GF setting the diver is comfortable with.

 

[grassybreakfast]

To answer the specific question, I'm quite sure AN/DP can be had without intro to tech - I know Advanced Recreational Trimix can be done without intro. Both would allow limited deco (perhaps not backgas deco for rec trimix, but you get to calculate either way) without adding a lot. Both are quite straight forward courses as long as you're squared away. (Doubles shutdown, buoyancy, No gas/no mask swims from memory). Iandt may still do the Kit-removal excercise.

My point is it's a 4 dive course which shouldn't require practice if you are in a position to do deco-dives already

That's interesting. I didn't know it's possible to do DP without intro. That would indeed not be a big burden. For back gas deco you wouldn't even need AN?