Cave Ccr Student Dies At Blue Grotto Today

[boulderjohn]

I don't dive a HUD... just two Petrel Twos.

I am not a rebreather diver, but I have had some recent experience looking at instruments in serious silt. I was in a narrow passage in a cave, with barely room for a couple people to be in it together. It was very silty, as expected, because I (and others) had been doing work in the area that had raised silt. I was working a few feet from the line. Suddenly it went from very silty (but workable) to completely silty. I couldn't see a thing. I wasn't concerned--I was close to the entrance with plenty of gas, there was enough flow to clear things out after a brief wait, and all I had to do was go upward to find the exit. Then I clearly saw something--the glow of a Petrel computer near my face. I could read it clearly. It was the only thing I could see.

It wasn't mine.

When I emerged a few minutes later, I realized that a two person team working farther back in the cave had exited, following the line. The silt cloud they created by their exit (and moving ahead of them with the flow) had created the sudden complete silt out. The first person on the team had passed me and exited without my knowing it. The second person was right next to me, nearly touching, without my knowing it--except I could see his Petrel clearly.

 

[DA Aquamaster]

Not sure I could read those numbers that close, @Jax. I think I would go on bailout for the few minutes I would be doing that skill.

Uh-oh. I hadn't considered the presbyopia factor.

It's another reason we got the optional HUDs on our KISS Sidekicks. I've noted that over the last few years my ability to read even the excellent display on a Shearwater Predator or Petrel has decreased to the point that I need reading lens in my mask, and in a silt out with the computer right up against my mask I wouldn't be able to read it. A three light HUD however is still easy to see and count the flashes even if the LEDs are not pinpoint sharp.

I also seriously considered the Shearwater NERD as it is focused at infinity and would again offer the ability to see the computer display even in a silt out. But I didn't want to spend $1900 on the NERD to support a $4500 rebreather. As a CCR student, I also didn't want the only display on the unit to be a near eye display that the instructor couldn't see as that would be a problem for the instructor. I also like being able to look at my team mates display and be able to read it from several feet away to verify PPO2 and that our deco status is close. NERDs remove that capability.

I might change down the road, but I'd still want a second system to monitor PPO2 and I suspect a NERD in front of one eye and a 3 LED HUD in front of the other would be a bit distracting, so it would be a NERD and Petrel.

might have poofed a bit of silt here and there, but I've never experienced a major silt out. Hoping to keep it that way, too!

Over the last 10 years of cave diving and in particular, the last 5 years of side mount cave diving, I'm become quite comfortable in silt outs, and having the time available that a CCR allows (in terms of both reduced deco and fewer gas consumption limits) is just gravy on top of the potatoes.

It's just another aspect of cave diving and once you've developed the skills for it, the challenges are enjoyable - but that also assumes you've selected and adapted your equipment and configuration for it.

 

[Pullnglide]

Forgive me but is the HUD many are mentioning just lights that either go out or turn red if the PO2 is endangering you? Do you know if the po2 is too low or too high by the lights? Also would you even be able to see a NERD in a complete silt out, isn't it outside of the mask?

 

[cerich]

It's another reason we got the optional HUDs on our KISS Sidekicks. I've noted that over the last few years my ability to read even the excellent display on a Shearwater Predator or Petrel has decreased to the point that I need reading lens in my mask, and in a silt out with the computer right up against my mask I wouldn't be able to read it. A three light HUD however is still easy to see and count the flashes even if the LEDs are not pinpoint sharp.

.

hearing ya on that...

 

[cerich]

Forgive me but is the HUD many are mentioning just lights that either go out or turn red if the PO2 is endangering you? Do you know if the po2 is too low or too high by the lights? Also would you even be able to see a NERD in a complete silt out, isn't it outside of the mask?

most are christmas tree, some are red or green

 

[jstrang]

Forgive me but is the HUD many are mentioning just lights that either go out or turn red if the PO2 is endangering you?

On the JJ HUD, which the student was using, the HUD has 3 columns, each representing an O2 cell. the top red blinks if the pO2 is over 1.6, the green light blinks if it is between 1.0 and 1.5, the yellow light blinks if it is between 0.5 and 1.0, and the bottom red light blinks if it below 0.4.

there is a buddy red light on the end of the HUD which blinks red if the pO2 is above 1.6 or below 0.4 - but that wouldn't have been visible if it was under a black out cover.

the solenoid would have been firing continuously too, and on the JJ it is easy to hear it.

 

[sea_ledford]

I don't dive a HUD... just two Petrel Twos.

Talk to Todd or Tiffany Winn at Silent O about an AV1 HUD. Worth every penny.

-Chris

 

[The Chairman]

I'm OK with the two Shearwaters. I don't want a HUD. I don't like them.

 

[chillyinCanada]

Why don't you like them?

 

[The Chairman]

You mean other than they are an equipment solution to a skills problem??? I like redundancy and consistency. This way I get two PDCs giving me redundant deco information and am able to see what's happening with my cells. My SF2 is an eCCR using Shearwater's Dive Cann bus system. It has two controllers: the one in the head and the one on my right wrist. If the right PDC dies the one in the head takes over, but then I don't know what my PPO2 or deco status is. A HUD would tell me only what my PPO2 is. With the second Petrel II, I can see cell mV, PPO2 and my Deco Status. Also, I don't feel a need to have lights flashing in my face. I check my Shearwaters quite often and don't need the added reminder.