PSAI Narcosis Management course - 73m on air

[northernone]

Raising the dead here.

Any recommendations who to contact to work towards this course?

I'm interested in consideration of encountering down wellings, runaway dive buddies and hypercapnia. I'd like to be narced as gracefully as possible which might improve my odds of not becoming a statistic if I find myself in these pearshaped situations. I'm also in cold low viz when home so managing narcosis is a reality much shallower.

My reasons of interest are my own, doubtless other's feelings will differ.

Willing to travel,
Cameron

P.s. any book or article recommendations as well are welcome.

 

[Kevrumbo]

Any physical activity that will raise your breathing rate at that depth will start the dark narc/CO2/Hypercapnia vicious cycle, and possibly increase the risk of an Ox-Tox seizure. If you really have to be down there at 73m on Air, use a DPV/Scooter to provide mobility --don't even think about kicking around manually & exerting yourself at all if you can help it. . .

. . .With the Scooter off and stowed, all it took was three hard & forceful frog kicks into the current at 80m depth, and I was instantly overcome with a narcotic CO2 hit: Hyperventilation & difficulty breathing the regulator, high density & flow viscosity of the Air mix & resulting Hypercapnia came on immediately. In the dim ambient light, the only thing I was able to perceive was my Petrel Computer flashing an expected extreme PPO2 Warning prompt of 1.9, and it took a few minutes focused concentration not to panic, just to hang onto a rig structure support beam and try to regain a nominal breathing rate & clear head before starting the ascent using the scooter. (Note: Elevated CO2 levels increase the likelihood of hyperoxic seizures as well). Not at all pleasant and I don't want to do that again. . .

 

[kensuf]

Deep, relaxed, controlled breathing too, the term is "diaphragmatic breathing". The bottom 1/3rd of your lungs are where most of the CO2 gas exchange happens, and you want to flush that out.

 

[rjack321]

Raising the dead here.

Any recommendations who to contact to work towards this course?

I'm interested in consideration of encountering down wellings, runaway dive buddies and hypercapnia. I'd like to be narced as gracefully as possible which might improve my odds of not becoming a statistic if I find myself in these pearshaped situations. I'm also in cold low viz when home so managing narcosis is a reality much shallower.

My reasons of interest are my own, doubtless other's feelings will differ.

Willing to travel,
Cameron

P.s. any book or article recommendations as well are welcome.

You will probably have to travel to SE Asia honestly. Which seems like a hell of a long way to go to be narced.

Trace is a PSAI instructor (or was) and can potentially refer you to qualified places.
Trace Malinowski

 

[Kevrumbo]

Interesting Q & A session at the end (49:00 to 51:00), on dealing with high gas density and attempting to recover from spiraling CO2 retention/poisoning due to extreme depth and/or hard physical exertion at any depth:

• Reduce workload;
• If possible switch to a lower Work-of-Breathing Gas (Trimix) and/or easier effort Underwater Breathing Apparatus (i.g. bailing out from CCR to Open Circuit Regulator);
• Abort dive and start prompt controlled ascent from depth ideally with the aid of a DPV Scooter;
• Last resort, try to eliminate negative static lung load: Open Circuit divers try a breathing position with head & upper body tilted down (fig D) past horizontal; CCR divers with back mounted counterlungs by rotating 180 degrees onto back in horizontal trim.

 

[Kevrumbo]

I had a close call this past summer that I was reluctant to post about -even as a lessons' learned & near miss experience- until now. I did another solo scooter open water bounce dive and brief excursion again, this time down to 90msw/300fsw on Air, after further reflection about the objectives of PSAI Narcosis Management Course.

My observations:

There is no way to "adapt" or gain tolerance for the extreme narcosis with progressively deeper dives following the PSAI Deep Air Course Levels 1 thru 6 (30m; 40m; 46m; 55m; 61m and 73m). Any work or exertion at these depths -66m and deeper- resulting in a heavy labored increased breathing rate (tachypnea and/or dyspnea) will immediately initiate the spiraling vicious cycle of CO2 retention/poisoning into Hypercapnic stupor and unconsciousness, along with the increased risk of Oxygen Toxicity Syndrome & Convulsions.

Even with a Scooter/DPV providing mobility to reach 90m and then only floating relaxed horizontally in neutral buoyancy, just the increased work-of-breathing due to the high gas density is potentially enough by itself to elicit CO2 retention along with compounding the anesthetic effects of extreme Nitrogen Narcosis.

27 Aug 2017.
Oil Rig Eureka Bounce Dive;
1min BT @ 90m depth (10ATA);
The ppO2 atm of Nitrox 21% (Air) @ 10ATA: 2.1
Gas Density @ 10ATA: 12g/L (approx 10x more dense than Air at surface);

Descent Rate (via DPV/Scooter): 30m/min;
SPG reading at Start of descent (10m depth): 180bar;
Depth Consumption Rate (Open Circuit) @ 10ATA: 20bar/min;
Amount of Gas consumed & used to inflate Wing & Drysuit on 3min descent to 10ATA: 40bar;
SPG reading at elapsed dive time 4min (3min descent plus 1min BT @ 10ATA): 120bar. In other words, 60bar total was used in 4min;

Ascent Rate: 10m/min from 90m to 15m.
Deco Time Required (on Air): 1min @9m; 3min @6m and 7min @3m;
Total Time of Dive: 30min;
SPG at End/Surface, remaining Air: 40 bar;

Single Tank Aluminium 13L with 210 bar initial fill;
Apeks XTX100 Regulator;
Dive Xtras X-Scooter Sierra, 150m depth rating;
Water temperature at depth: 14 deg C.

The scary part other than the black abyss outside my primary light source, was the temptation to just drift off with the anesthesia of the extreme N2 Narcosis -and that was within one minute at 90msw with no physical activity, but with increasing work-of-breathing trying to expel metabolic CO2 even in a non-exertion, "resting" state floating neutrally buoyant. In other words, even though completely relaxed with slow and deep inhalation & exhalation respiratory cycles, I couldn't get rid of Carbon Dioxide fast enough because of the higher Air density at that depth -it just became too hard to breathe efficiently anymore without going into prompt Hypercapnia.

Anyway, here are some forum posts below from the past four months with reference links in which I alluded to my 90m dive experience above:

Should I go Full Metric from the Start ?
PADI tech 50 no refill between dives
Accident on Southern Cal Oil Rigs Dive

 

[northernone]

I had a close call this past summer that I was reluctant to post about -even as a lessons' learned & near miss experience- until now. I did another solo scooter open water bounce dive and brief excursion again, this time down to 90msw/300fsw on Air, after further reflection about the objectives of PSAI Narcosis Management Course.

My observations:

The scary part other than the black abyss outside my primary light source, was the temptation to just drift off with the anesthesia of the extreme N2 Narcosis -and that was within one minute at 90msw with no physical activity, but with increasing work-of-breathing trying to expel metabolic CO2 even in a non-exertion, "resting" state floating neutrally buoyant. In other words, even though completely relaxed with slow and deep inhalation & exhalation respiratory cycles, I couldn't get rid of Carbon Dioxide fast enough because of the higher Air density at that depth -it just became too hard to breathe efficiently anymore without going into prompt Hypercapnia.

Anyway, here are some forum posts below from the past four months with reference links in which I alluded to my 90m dive experience above:

Should I go Full Metric from the Start ?
PADI tech 50 no refill between dives
Accident on Southern Cal Oil Rigs Dive

Significant experience. Glad you wrote up your observations.

Respectfully,
Cameron

 

[Kevrumbo]

Significant experience. Glad you wrote up the experience.

Respectfully,
Cameron

. . .There is no way to "adapt" or gain tolerance for the extreme narcosis with progressively deeper dives following the PSAI Deep Air Course Levels 1 thru 6 (30m; 40m; 46m; 55m; 61m and 73m). Any work or exertion at these depths -66m and deeper- resulting in a heavy labored increased breathing rate (tachypnea and/or dyspnea) will immediately initiate the spiraling vicious cycle of CO2 retention/poisoning into Hypercapnic stupor and unconsciousness, along with the increased risk of Oxygen Toxicity Syndrome & Convulsions.

Even with a Scooter/DPV providing mobility to reach 90m and then only floating relaxed horizontally in neutral buoyancy, just the increased work-of-breathing due to the high gas density is potentially enough by itself to elicit CO2 retention along with compounding the anesthetic effects of extreme Nitrogen Narcosis.

27 Aug 2017.
Oil Rig Eureka Bounce Dive;
1min BT @ 90m depth (10ATA);
The ppO2 atm of Nitrox 21% (Air) @ 10ATA: 2.1
Gas Density @ 10ATA: 12g/L (approx 10x more dense than Air at surface);

Descent Rate (via DPV/Scooter): 30m/min;
SPG reading at Start of descent (10m depth): 180bar;
Depth Consumption Rate (Open Circuit) @ 10ATA: 20bar/min;
Amount of Gas consumed & used to inflate Wing & Drysuit on 3min descent to 10ATA: 40bar;
SPG reading at elapsed dive time 4min (3min descent plus 1min BT @ 10ATA): 120bar. In other words, 60bar total was used in 4min;

Ascent Rate: 10m/min from 90m to 15m.
Deco Time Required (on Air): 1min @9m; 3min @6m and 7min @3m;
Total Time of Dive: 30min;
SPG at End/Surface, remaining Air: 40 bar;

Single Tank Aluminium 13L with 210 bar initial fill;
Apeks XTX100 Regulator;
Dive Xtras X-Scooter Sierra, 150m depth rating;
Water temperature at depth: 14 deg C.

One additional compounding factor to consider as well was the water temperature:

Cold Shock Response lasts for only about a minute after entering the water and refers to the affect that cold water has on your breathing. Initially, there is an automatic gasp reflex in response to rapid skin cooling. . . [Usually not a severe issue jumping in cold water in a drysuit with appropriate insulating undergarments]

A second component of the Cold Shock Response involves hyperventilation. Like the gasp reflex, this is a natural reaction to the cold. Although this physiological response will subside, panic can cause a psychological continuance of hyperventilation. Prolonged hyperventilation can lead to [CO2 retention, Hypercapnia and additive effects of Nitrogen Narcosis at deep depths], so the key thing is to concentrate on controlling your breathing. . .

http://beyondcoldwaterbootcamp.com/4-phases-of-cold-water-immersion#Cold Shock Response

 

[DevonDiver]

Deep, relaxed, controlled breathing too, the term is "diaphragmatic breathing". The bottom 1/3rd of your lungs are where most of the CO2 gas exchange happens, and you want to flush that out.

Very interesting video by Simon Mitchell. Seems to strongly imply that fancy breathing techniques would be about as useful as a chocolate frying pan when dealing with the gas densities achieved on the deep air course...

 

[JohnnyC]

@northernone Protec Playa has the book, although I sort of have the feeling that it's part of being a PSAI shop, not that they have any desire to teach the course. Could give them a shout if you really wanted to. I'd be willing to be it would be pretty expensive though, both to deter divers from asking for it, and to cover the cost of the helium the instructors will no doubt be breathing....

My personal recommendation would be to direct you towards someone willing to do mixed gas training. With more agencies slowly but surely coming along to embrace putting helium in bottles that stay much shallower, you're more and more likely to get people diving say 21/35 or 30/30. Hedges your bets against things like downcurrents, runaway buddies, etc. while being beneficial for all of the reasons that kevrumbo already mentioned.

Personally, I think "recreational" trimix should be like nitrox, eLearning, take a test, no dives required.