Non professional divers taking very young children diving (even in a pool)

[packrat12]

"With small children, the fear is the potential damage caused by the higher ambient pressure on growing bones." - That is one of the concerns I know of with children diving deeper (probably diving in general). It is a concern specifically with the hearing parts overall but I do not remember specifically which although I do not think it was the 3 primary hearing bones. Ironically my daughter and I sat with Dick Rutkowski when she was 12 and talked about this specific issue. We also have talked with her about this over the years. Not sure that we will every see good studies as it would probably be 'un-ethical' to do them on the children, although I am sure my daughter would volunteer.

The only issue I raise(d) is that the first 30' has the most significant pressure change, e.g. 2x. I would assume that the first 30' is the most damaging.

 

[bl6394]

Packrat12 - I'm sorry if anything I said was interpreted by you as misinformation.

As a PADI instructor - I am only permitted to take a 12-14 year old to 70 feet in a continuing education setting. Likewise - I'm unable to take them on Cavern / Cave dives, dives involving accelerated decompression, ice, rebreather, or sidemount. These limitations are imposed upon me by my training agency.

If your experience and/or training allows you to do otherwise - great!

Safe diving,

 

[packrat12]

Bjorn,

100% agree with everything you just said!! and I think they are a valid and logical limitations imposed by agencies during the training process. I personally am not sure which way I am on technical level diving with mid-age youth (15?, 16? 17?). Definitely NO on young divers (10-15) due to the risks vs benefits along with available time for individual experience and skills.

Safe diving also!

 

[boulderjohn]

The only issue I raise(d) is that the first 30' has the most significant pressure change, e.g. 2x. I would assume that the first 30' is the most damaging.

That is true for the compression of gases. That is not what we are talking about. We are talking about the effects of total pressure on growing tissues.

A child diving at 60 FSW is under less than 3 atmospheres of pressure (2.82). A child diving at 130 FSW is under nearly 5 atmospheres of pressure (4.94).

 

[packrat12]

That is true for the compression of gases. That is not what we are talking about. We are talking about the effects of total pressure on growing tissues.

A child diving at 60 FSW is under less than 3 atmospheres of pressure (2.82). A child diving at 130 FSW is under nearly 5 atmospheres of pressure (4.94).

Right but we still have that major change at 2x (33') which only gradually changes as we go deeper. We also spend longer shallower we are.

If I remember right, one of the bones in question does not fully close until about 25 years old or older so some of these issues apply to young adults.

Still would be an interesting study to do.

 

[boulderjohn]

Right but we still have that major change at 2x (33') which only gradually changes as we go deeper.

The air in your BCD and your wet suit will indeed change more rapidly with depth changes in shallower water. Is that what we are discussing?

 

[packrat12]

The air in your BCD and your wet suit will indeed change more rapidly with depth changes in shallower water. Is that what we are discussing?

I understand that part of Boyle's law but from my understanding (I am not a doctor nor did I stay at a Holiday Inn Express recently), I would imagine that the idea of being deep as a problematic threshold point (like a line in the sand) is not the issue so much as the pressure changes in general to the body. Because of that, I would also imagine that the initial 2x would cause the most physiological changes to the body, further changes add to it. Basically the idea of 2ATM -> 5 ATM but also 2X -> 5X with the most rapid per foot changes in the first 33' which I would also imagine is the most traumatic to our bodies. Affects (any) of high partial pressures of gasses are obviously more pronounced deeper.

As an issue I think we are in agreement that this is an understudied that does have potential for detrimental effects. In general, I believe that diving causes detrimental effects to humans but not so much so that we can not 'safely' do it. I believe that I have some issues with hearing and tinnitus that were either caused or aggravated by my younger diving. If they were affected by diving, I still would not have changed a thing.

 

[nimoh]

I understand that part of Boyle's law but from my understanding (I am not a doctor nor did I stay at a Holiday Inn Express recently), I would imagine that the idea of being deep as a problematic threshold point (like a line in the sand) is not the issue so much as the pressure changes in general to the body. Because of that, I would also imagine that the initial 2x would cause the most physiological changes to the body, further changes add to it. Basically the idea of 2ATM -> 5 ATM but also 2X -> 5X with the most rapid per foot changes in the first 33' which I would also imagine is the most traumatic to our bodies. Affects (any) of high partial pressures of gasses are obviously more pronounced deeper.

As an issue I think we are in agreement that this is an understudied that does have potential for detrimental effects. In general, I believe that diving causes detrimental effects to humans but not so much so that we can not 'safely' do it. I believe that I have some issues with hearing and tinnitus that were either caused or aggravated by my younger diving. If they were affected by diving, I still would not have changed a thing.

If the problem was caused by rate of pressure change, then we would address it with slower descent and ascent rates. However, the problem is caused by total pressure so we address it with depth limitations for junior divers.

 

[redacted]

Great, so despite Grandpa having shown signs of poor judgment, the shop weighs the risk and reward, and figuring that the risk of anyone getting hurt by Grandpa's little adventure is low, decides to do business this one time. Grandpa likes the shop's great customer service and comes back for another tank so HE can go diving in the local lake by himself, as he managed to get someone to fix his ancient reg. This is not someone the shop wants to keep doing business with.

I was referring only to the specific case of the Grandpa, not "this sort of thinking." Did you walk into the shop with an ancient reg and ask to have it fixed or whether they had any cheap regs so you could put your grandson on scuba in a pool? To me, "this sort of thinking" is simply a dive shop owner using her brain to make a judgment based on what a customer told her on the spot about his intentions.

You seem to like the term "ancient reg". What are you trying to connote with that term? Are you suggesting it is like an ancient scotch whisky? Or, perhaps, that there is some inherent danger in an older regulator? If the latter, what do you think the danger might be in an older regulator as compared to a newer regulator.

The risk vs reward idea is rather interesting also. Do you think the shop's response might have been different if the grandfather walked in with his $15k credit line CC and told the shop he wanted to outfit his 8 Y/O grandson with a complete set of scuba gear?

 

[packrat12]

If the problem was caused by rate of pressure change, then we would address it with slower descent and ascent rates. However, the problem is caused by total pressure so we address it with depth limitations for junior divers.

I am not talking about rate of change during ascent/descent. I am talking about per foot of the multiple of pressure change (I really do not know how to say it correctly). We double the pressure in the first 33' while only tripling pressure (50% more) at 66'. I would suspect that the most significant physiological change is at the 0 --> 33' range. Keep in mind that it is still linear change per foot so again for an understudied event, what statistically shows a difference for a given depth? I suspect most of the damage is done from 0 --> 33' regardless of final depth. I also suspect that any depth limitation specifically addressing youth divers is arbitrary and based on limited information and assumptions.

Here is a good article (hope I can link it as it is a very relevant article) on the issues boulderjohn and nimoh are talking about. I think this area needs honest discussion and study. Over all, there are no specific depth limitations beyond normal Rec and Training, from PADI, after 12 yrs. Awareness of potential issues is also key and would indeed be a good education point from the agencies to parents of youth divers and youth students. Note that this article has one highlighted comment, to paraphrase - "There is insufficient medical evidence for or against youth diving. "

http://www.danap.org/DAN_diving_safety/DAN_Doc/pdfs/young2.pdf