What went wrong on your dive today/recently? And what did you learn?

[John C. Ratliff]

@John C. Ratliff,

I was thinking that you are/were an E-4/E-6 color slide photographer who developed his own slides. Did you do this in addition to shooting Kodacolor color negatives?

rx7diver

Yes, I did some E-6 development, but mostly sent it out. It is a time-consuming process, and at times I was taking photos faster than I could develop it. I do have strips of Ectachrome slide film in a negative holder, as I never mounted them. I’ll have to look again, as some of those were underwater slides too.

SeaRat

 

[Wibble]

Was mildly rushed this weekend as the boat needed to get into the lock.

I did the usual thing and grabbed the marina key to get to the toilets to put on the catheter for the forthcoming dive. I rushed it a bit and obviously didn't take enough care to choke the chicken and ensure it's all properly stuck on.

Of course, during the dive the inevitable happened. That damp feeling around the lower torso. Grr.

Back on the boat it was clear that it really hadn't stuck at all and the nether regions were soaked.

Full washload back home and the shiny new BZ400 heated undersuit was christened.

The sort of good news was the next day's diving was cancelled due to the poor weather.

Will probably mount the catheter at home next weekend. Sounds like some form of euphemism!

Lesson: Rushing always ends in tears.

 

[Pressurehead]

Turns out having an inexpensive spare in my save-a-dive kit was handy.

Same happened to me, except I had a old bottom timer in my spare kit , that is all she needed .
I had a spare Shearwater peregrine as a back for my Perdix AI, no, not going to happen.

 

[UofMI_Divegeek]

Would be interesting to hear of people's incidents and what you learned from it.

This is most relevant to those using oxygen enriched air (Nitrox)
A more detailed account of this is at:

A Little Knowledge

www-personal.umich.edu

After several hundred dives in the Port Huron region of the St. Clair River (one of North America's most intense navigable waterways ... current under the Blue Water Bridge can exceed 10 knots), we were looking for something a bit more challenging (thrilling). We decided to do a "fly" (never touch the bottom) under the Blue Water Bridge starting from the mouth of the St Clair river to our favorite exit spot, the (now non-accessible) Bramble dock. Since we knew the current would be intense and this dive would require major physical exertion, we chose to do the dive using an oxygen enriched air breathing gas (NOAA I or 32 % oxygen). Our thinking was the added oxygen would facilitate the anticipated extreme aerobic exertion of the dive.

Our plan was to enter above the mouth of the St. Clair River, drop down into the main channel (~60 ffw) and then to be rapidly hurled downstream. After 12 minutes, we would move to a posture at right angles to the current and vigorously swim until we reached a bottom contour. Then, we would use our "river sticks" (see River diving lecture slides that illustrate our specialized river diving equipment) to facilitate moving towards the exit point.

At 12 minutes, we went to right angles to the current and started swimming. Shortly after doing this, I felt enormously tired ... more tired than I have ever been underwater. This surprised (and concerned) me 'cause I considered myself to be in excellent physical condition (At this time, I was doing an hour a day of high-impact aerobics from national champion aerobic instructors at a studio known for its intense workouts. I was even a token male on their aerobics exercise TV program). The experienced fatigue was extreme. Once reaching the river bottom, we stopped several times with our "river sticks" embedded in the river bottom to hold position while we caught our breath. We reached our exit point (after covering a total of ~1.5 miles (2.4 km) ) in 14 minutes. 1.5 miles in 26 minutes means our average downstream speed was ~ 3.5 miles/hour ( 5.6 km/hr, 3.03 knots.)

I did not understand why we both had felt so fatigued (air starved) on the dive.

A few years later, I ran across an article in Undersea Biomed Research where the Israeli military reported that the slightly increased density of oxygen enriched air exacerbated CO2 retention. We then repeated this dive on compressed air and did not experience the sensation of massive air starvation associated with our earlier dives. So, I now believe that the extreme fatigue we both experienced was a result of unanticipated CO2 retention.

We thought we were being clever in using an oxygen enriched air mix, but it turns out that our cleverness worked against us on that particular dive.

The points Emphasized:

1. A little (insufficient) knowledge can be a dangerous thing.

2. In diving, as in life, it is the unknown that can pose a significant risk

3. Divers doing physical tasks on oxygen enriched air (Nitrox) should pay particular attention to symptoms of CO2 build-up.

4. No matter how much is known, there is always more to learn.

 

[Rollin Bonz]

I learned something today. When you hide your spare car keys under the rock you keep for that purpose and put the key (in ziplock bag) and rock on your car hood after the dive, don't drive away with them on there. I did retrieve them (unlike the time I left them on the base of the windshield and drove away-- to the tune of a $250 US replacement). DAMN those chip keys the last 15 years !!!

Similar experience, but worse.

When unpacking your gear at home after a day of diving, NEVER EVER EVER take your Perdix AI out of your vehicle and place it on the roof to dry thinking you'll grab it later to take it in to sync your dives. You won't. What you will do is go to work the next day, then, when you get home and decide to sync your dives, realize what you did, spend 30 minutes (if you're lucky) searching the sides of the road to find the shattered remains of your beloved DC

Result: Second most extensive repair ever completed by Dive-Tronix (shout out to Richard)

 

[SlugLife]

and place it on the roof to dry thinking you'll grab it later

Placing anything on your vehicle roof thinking you'll grab it later (even a few seconds later) IMO is always a terrible life plan.

I've just seen that end in disaster far, far, far more times than I can count which is why I don't do it as a rule. Learn from other people doing it the hard way. The closest I've come to that is putting something on the front driver's side of the windshield where I'll see it.

For things like gas-caps & oil-caps, I usually try to attach it in some way, whether using zip-ties, paracord, etc so I don't have to hold it or put it somewhere.

 

[Pressurehead]

Placing anything on your vehicle roof thinking you'll grab it later (even a few seconds later) IMO is always a terrible life plan.

Off topic, which is usual.
Like the time I saw a bloke place his new surfboard on the roof racks [to tie down later], only to drive away and for it to fly off and smash on the road.
I did the same with a pair of reading glasses, left on the car, found broken in the driveway.

 

[Rollin Bonz]

Placing anything on your vehicle roof thinking you'll grab it later (even a few seconds later) IMO is always a terrible life plan.

I've just seen that end in disaster far, far, far more times than I can count which is why I don't do it as a rule. Learn from other people doing it the hard way. The closest I've come to that is putting something on the front driver's side of the windshield where I'll see it.

For things like gas-caps & oil-caps, I usually try to attach it in some way, whether using zip-ties, paracord, etc so I don't have to hold it or put it somewhere.

Never place anything you wish to keep anywhere on a highly mobile object...

 

[johndiver999]

This is most relevant to those using oxygen enriched air (Nitrox)
A more detailed account of this is at:

A Little Knowledge

www-personal.umich.edu

After several hundred dives in the Port Huron region of the St. Clair River (one of North America's most intense navigable waterways ... current under the Blue Water Bridge can exceed 10 knots), we were looking for something a bit more challenging (thrilling). We decided to do a "fly" (never touch the bottom) under the Blue Water Bridge starting from the mouth of the St Clair river to our favorite exit spot, the (now non-accessible) Bramble dock. Since we knew the current would be intense and this dive would require major physical exertion, we chose to do the dive using an oxygen enriched air breathing gas (NOAA I or 32 % oxygen). Our thinking was the added oxygen would facilitate the anticipated extreme aerobic exertion of the dive.

Our plan was to enter above the mouth of the St. Clair River, drop down into the main channel (~60 ffw) and then to be rapidly hurled downstream. After 12 minutes, we would move to a posture at right angles to the current and vigorously swim until we reached a bottom contour. Then, we would use our "river sticks" (see River diving lecture slides that illustrate our specialized river diving equipment) to facilitate moving towards the exit point.

At 12 minutes, we went to right angles to the current and started swimming. Shortly after doing this, I felt enormously tired ... more tired than I have ever been underwater. This surprised (and concerned) me 'cause I considered myself to be in excellent physical condition (At this time, I was doing an hour a day of high-impact aerobics from national champion aerobic instructors at a studio known for its intense workouts. I was even a token male on their aerobics exercise TV program). The experienced fatigue was extreme. Once reaching the river bottom, we stopped several times with our "river sticks" embedded in the river bottom to hold position while we caught our breath. We reached our exit point (after covering a total of ~1.5 miles (2.4 km) ) in 14 minutes. 1.5 miles in 26 minutes means our average downstream speed was ~ 3.5 miles/hour ( 5.6 km/hr, 3.03 knots.)

I did not understand why we both had felt so fatigued (air starved) on the dive.

A few years later, I ran across an article in Undersea Biomed Research where the Israeli military reported that the slightly increased density of oxygen enriched air exacerbated CO2 retention. We then repeated this dive on compressed air and did not experience the sensation of massive air starvation associated with our earlier dives. So, I now believe that the extreme fatigue we both experienced was a result of unanticipated CO2 retention.

We thought we were being clever in using an oxygen enriched air mix, but it turns out that our cleverness worked against us on that particular dive.

The points Emphasized:

1. A little (insufficient) knowledge can be a dangerous thing.

2. In diving, as in life, it is the unknown that can pose a significant risk

3. Divers doing physical tasks on oxygen enriched air (Nitrox) should pay particular attention to symptoms of CO2 build-up.

4. No matter how much is known, there is always more to learn

You really think that the breathing gas density was a problem at just 60 feet? I've done high exertion dives at much higher gas densities without suffering this problem. Perhaps you learned to better ventilate after the first dive with all the problems? I've never heard of this sort of thing before.

 

[scubadada]

This is most relevant to those using oxygen enriched air (Nitrox)
A more detailed account of this is at:

A Little Knowledge

www-personal.umich.edu

After several hundred dives in the Port Huron region of the St. Clair River (one of North America's most intense navigable waterways ... current under the Blue Water Bridge can exceed 10 knots), we were looking for something a bit more challenging (thrilling). We decided to do a "fly" (never touch the bottom) under the Blue Water Bridge starting from the mouth of the St Clair river to our favorite exit spot, the (now non-accessible) Bramble dock. Since we knew the current would be intense and this dive would require major physical exertion, we chose to do the dive using an oxygen enriched air breathing gas (NOAA I or 32 % oxygen). Our thinking was the added oxygen would facilitate the anticipated extreme aerobic exertion of the dive.

Our plan was to enter above the mouth of the St. Clair River, drop down into the main channel (~60 ffw) and then to be rapidly hurled downstream. After 12 minutes, we would move to a posture at right angles to the current and vigorously swim until we reached a bottom contour. Then, we would use our "river sticks" (see River diving lecture slides that illustrate our specialized river diving equipment) to facilitate moving towards the exit point.

At 12 minutes, we went to right angles to the current and started swimming. Shortly after doing this, I felt enormously tired ... more tired than I have ever been underwater. This surprised (and concerned) me 'cause I considered myself to be in excellent physical condition (At this time, I was doing an hour a day of high-impact aerobics from national champion aerobic instructors at a studio known for its intense workouts. I was even a token male on their aerobics exercise TV program). The experienced fatigue was extreme. Once reaching the river bottom, we stopped several times with our "river sticks" embedded in the river bottom to hold position while we caught our breath. We reached our exit point (after covering a total of ~1.5 miles (2.4 km) ) in 14 minutes. 1.5 miles in 26 minutes means our average downstream speed was ~ 3.5 miles/hour ( 5.6 km/hr, 3.03 knots.)

I did not understand why we both had felt so fatigued (air starved) on the dive.

A few years later, I ran across an article in Undersea Biomed Research where the Israeli military reported that the slightly increased density of oxygen enriched air exacerbated CO2 retention. We then repeated this dive on compressed air and did not experience the sensation of massive air starvation associated with our earlier dives. So, I now believe that the extreme fatigue we both experienced was a result of unanticipated CO2 retention.

We thought we were being clever in using an oxygen enriched air mix, but it turns out that our cleverness worked against us on that particular dive.

The points Emphasized:

1. A little (insufficient) knowledge can be a dangerous thing.

2. In diving, as in life, it is the unknown that can pose a significant risk

3. Divers doing physical tasks on oxygen enriched air (Nitrox) should pay particular attention to symptoms of CO2 build-up.

4. No matter how much is known, there is always more to learn.

This is implausible. According to MultiDeco, the gas density for air and 32% at 60 ft are both just 3.4 g/l