Dumb scuba products

[M-Cameron]

It is usually assumed that a not-technical diver is always well within NDL limits, hence if the ascent happens at reasonable speed he can safely surface without any deco stop. This device is intended for solo diving, a practice which is never safe outside NDL.
It remains to be proven that after such a mechanically-controlled automatic ascent a passed-by solo diver has any chance of being rescued, if no one is looking after her/him at the surface...

ide recon their chances of being found are 10000x better at the surface than they would be 60' under water.....even if it is just a body recovery at that point.

frankly ide just be worried about it malfunctioning and blasting me to the surface unintentionally.

ive not seen any statistics on how many divers die underwater by not being able to consciously make it to the surface...but doing some quick googling lead me to this:

Diving fatality data published in Diving Medicine for Scuba Divers (2015)[3]

• 90% died with their weight belt on.
• 86% were alone when they died (either diving solo or separated from their buddy).
• 50% did not inflate their buoyancy compensator.
• 25% first got into difficulty on the surface
• 50% died on the surface.
• 10% were under training when they died.
• 10% had been advised that they were medically unfit to dive.
• 5% were cave diving.
• 1% of rescuers died.

DAN was notified of 127 recreational scuba deaths during 2015. 67 were actively investigated by DAN[10]

so if 25% first got into distress on the surface, that means 96 divers were in trouble underwater......and if 50% of them died on the surface, then 48 died underwater......

so this device would have potentially saved around 30-70 people annually....


in a sport where the fatality rate is 1.8 per million recreational dives.....it honestly seems like a greater liability than anything else.

 

[Angelo Farina]

M-Cameron, from your analysis I would conclude that this device could have forcedly surfaced 30-70 divers per year, which per se is good.
What I doubt if those surfaced divers can be counted "saved" or simply "dead body rescued"...
And you have to counter-weight how many accidental and not-required forced resurfacing events occur each year in case this device becomes common equipment for all divers. How many of them result in health problems or even deaths?
When a new technology is introduced, a serious analysis of benefits vs risks should be undertaken. I am not skilled on this topic so I have no elements for drawing the final line of this balance. But I can see both the advantages and the risks...

 

[JackD342]

What if there is a system failure and it takes you up, blowing the safety stop?

Exactly. A great idea if it works and is foolproof and/or "fails safe," but a terrible idea if it is not reliable.
I just spent a little time on their website. First, the "BUY" button says they are out of stock, no hint of availability. So maybe there is enough $$ on hand to keep the website up for now, but production is done or tenuous.

What happens if it inflates when you don't want it to? Disconnect the LP inflator hose, the same as if your "normal" inflator sticks. Unless it is prone to more frequent failure in that mode, then that is not really a big deal as long as your training is refreshed. We already dive with equipment that sometimes inflates when we don't want it to.

The description on the site says that after no detection of breathing for 40 seconds, it will alarm for another 20 seconds, and then auto-inflate. So, a full minute of no breathing and no response. The functional flow diagram is slightly different, so they probably tweaked those parameters over time and failed to update some info at some point.

After reviewing the site, and the pedigree for the DiverGuard team, I now have a more positive impression of the item. I wonder when was the last time that anything was produced/sold.

 

[akdeepdiver]

Dumbest Scuba product- the NITROX Spare air

 

[Bob DBF]

Although these are some interesting observations, it's not all that easy to sort it out. These are all observations after the fact. Time of death is rather tricky since most places it takes a medical proffessional to call the death, and that may not happen for hours after the accident.

so if 25% first got into distress on the surface, that means 96 divers were in trouble underwater......and if 50% of them died on the surface, then 48 died underwater......

Using your method:

90% died with their weight belt on.

That would mean 13 survived long enough for rescuers to remove their weight belt to begin the rescue. Now it seems to me that scenario may be closer to the truth, but there is no data in those bullet points to support that conclusion.


I have gotten rather p*ssed off for a BC inflating on it's own, I'll be d*mned if I have one that is designed to do that as a feature.


Bob

 

[tridacna]

I just spent a little time on their website. First, the "BUY" button says they are out of stock, no hint of availability. So maybe there is enough $$ on hand to keep the website up for now...

Everyone relax. They’ve been outta biz since DEMA 2012. Never lifted off after that.

 

[JackD342]

ide recon their chances of being found are 10000x better at the surface than they would be 60' under water.....even if it is just a body recovery at that point.

frankly ide just be worried about it malfunctioning and blasting me to the surface unintentionally.

ive not seen any statistics on how many divers die underwater by not being able to consciously make it to the surface...but doing some quick googling lead me to this:

Diving fatality data published in Diving Medicine for Scuba Divers (2015)[3]

• 90% died with their weight belt on.
• 86% were alone when they died (either diving solo or separated from their buddy).
• 50% did not inflate their buoyancy compensator.
• 25% first got into difficulty on the surface
• 50% died on the surface.
• 10% were under training when they died.
• 10% had been advised that they were medically unfit to dive.
• 5% were cave diving.
• 1% of rescuers died.

DAN was notified of 127 recreational scuba deaths during 2015. 67 were actively investigated by DAN[10]

so if 25% first got into distress on the surface, that means 96 divers were in trouble underwater......and if 50% of them died on the surface, then 48 died underwater......

so this device would have potentially saved around 30-70 people annually....


in a sport where the fatality rate is 1.8 per million recreational dives.....it honestly seems like a greater liability than anything else.

I think you are applying those percentages incorrectly. I read that list as each percentage applies to the entire population and none are mutually exclusive; not enough info to determine overlapping sets. So a single diver that initially gets into trouble on the surface may sink with a weight belt on while training and die underwater without inflating their BCD. That is one person covered by 4 different measures.

 

[M-Cameron]

I think you are applying those percentages incorrectly. I read that list as each percentage applies to the entire population and none are mutually exclusive; not enough info to determine overlapping sets. So a single diver that initially gets into trouble on the surface may sink with a weight belt on while training and die underwater without inflating their BCD. That is one person covered by 4 different measures.

i know, thats why my final tally was a fairly large margin between the most extreme of the percentages, because some of them can stack...wasnt intending to be scientific, just to give us a basis for conversation ...either way whether its 20 or 100 its statistically insignificant considering there are millions of dives every year and only a hand full of accidents that result in fatalities.

 

[tridacna]

Dumbest Scuba product- the NITROX Spare air

Dang. I thought you were making that up. Then I saw the Tri-mix Spare Air. Unbelievable.

 

[Snoweman]

I'm going to go with the CO2 backup for inflating a BCD.