Rebreather Pro

Video: Jill Heinerth Rebreather Message

Jill Heinerth — Tue, 07 Feb 2012 12:31:41 PST

Steve Lewis' Blog: Accident analysis

Jill Heinerth — Mon, 06 Feb 2012 07:04:17 PST

Our friend and colleague, Steve Lewis (Doppler), with another thought provoking and well-presented essay on his blog at Doppler's Tech Diving Blog. If you are in the mood for, thoughtful, well-wriiten tech diving news and analysis, sign up and follow Steve!

BOOM!

Jill Heinerth — Mon, 30 Jan 2012 17:15:14 PST

Things That Go Boom:

Over a decade ago, I was diving in a Florida cave at 300 feet of depth when a very loud “boom” erupted behind me. The sound was like someone was bashing large SCUBA cylinder against the wall of the cave. In rapid succession, my solenoid began firing erratically and injecting pure oxygen into a loop that was previously stable at 1.2. I quickly shut down the oxygen tank valve and tried to figure out what had occurred. My primary handset was flickering strange information that looked like it was communicating a language akin to Klingon. Luckily my secondary display was unaffected by whatever had just occurred. I use the secondary display to carry me out of the cave and through the many levels of decompression ahead, feathering my tank tank and injecting oxygen as I needed it. To be honest, the exit was relatively routine. I had practiced manual control often and even preferred a hybrid manual approach to conserve oxygen on ascent and deco in any case. After the dive, I stripped out of my rebreather to determine the cause of the loud noise and discovered a gaping hole in the back of my rebreather where a lithium battery had exploded out of the back of the black box. It was still sizzling and popping after all that time in the water. I was grateful for several features of my rebreather. The completely redundant oxygen display offered me an instrument panel with which to fly the rig in manual mode reliably. The batteries were NOT contained within the breathing loop and therefore did not cause an unrecoverable loop failure. Think about your own rebreather. Would it have coped with a leaking or explosive battery? Could you finish this dive on the loop? -- Jill Heinerth

Off to Stockholm to speak at Tech-Dive 2012

Jill Heinerth — Thu, 26 Jan 2012 20:31:05 PST

Here is the information. Please come to my presentation and say hello! http://tech-diving.se/2012/

Have you got your Rebreather Forum 3 tickets yet?

Jill Heinerth — Fri, 13 Jan 2012 04:02:14 PST

RF3 is quickly approaching. There are some good deals on early ticket purchases. Click here.

Keeping warm during your dive

Jill Heinerth — Sun, 08 Jan 2012 13:16:56 PST

Why it is important to keep warm throughout your dive?

When we have adequate thermal protection, we tend to enjoy our dives much more than when we are cold, but adequate thermal protection goes far beyond comfort. Let’s envision a typical deep diving scenario and look at what happens to the human body during that exposure. Even in the coldest water, we seems to be able to tolerate the descent and bottom time adequately. We are working hard on that segment of the dive and moving enough to maintain good circulation. During decompression, our body chills because of inactivity and exposure time. When the body chills, the brain sends a signal to the extremeties to shut down the circulation and put an emphasis on maintaining core temperature. Just when we need to be off-gassing the entire body, our brain is sending a message to prioritize circulation to the body core. If we further chill during a long decompression, the circulation is prioritized to a smaller and smaller, more critical body core and brain.

If you feel that your hands and feet are getting chilled, then that is a signal that they are not just cold, but perhaps not off-gassing properly. Exit the water, move around, and you may be sending a nice cascade of trouble to the rest of your body. This is not an argument for heating the body on decompression though, it is actually a call to keep better constant thermal regulation through both the bottom time AND the decompression.

Its not just about comfort. It is critical to good balanced decompression.

CLICK HERE for an Advanced Diver Magazine feature about Jill's Antarctic cave diving exploration.

-- Jill Heinerth

When Should I Start CCR Diving

Jill Heinerth — Thu, 29 Dec 2011 07:10:01 PST

I just received a question from the "Ask Jill" link that is worth sharing.

A reader with a young family was eager to start rebreather diving but was somewhat financially strapped, wondering whether purchasing an older used unit was a good idea. Learning on any rebreather gives you an opportunity to build hours on CCR technology and that knowledge will transfer to other units in the future. However, the most important thing to secure is excellent training and to dedicate yourself to very diligent behavior using checklists at all times. It is a very big decision when you have a young family, because there is additional risk involved with rebreather diving.

Accidents generally result from how we use the equipment rather than equipment failure. So ultimately we have a reasonable ability to control our results. If you choose to buy a used rebreather, you should send it to the manufacturer for assessment and service. There may be small issues or developing problems that you are not trained to detect. The factory should be able to find those problems and fix them, giving you peace of mind to begin your journey.

I'm a tough person to ask about jumping into rebreather diving. I love it, but am very cautious. CCRs are tools, not toys. You need to have a purpose for a CCR, not simply a desire to use one. I don't like suggesting that anyone take on additional risk in life. If I had a young child, I would ask myself... "should I start rebreather diving with something less than I really want?" or "should I wait until I have saved enough money to buy the best unit and training I can afford?" Ultimately only you can answer that question adequately. It is a tough one, but make sure your whole family embraces it and understands why you do what you love! -- Jill Heinerth

Rebreather CO2 Incident

Jill Heinerth — Sun, 25 Dec 2011 19:37:13 PST

CO2 Incident

I’ve posted this video link before, but I want to highlight it again, because there is so much to learn from this incident:

http://www.hse.gov.uk/diving/video/co2video.htm

This time you view it I would like you to consider bailout volume and scrubber ratings. Many people look at the scrubber rating that is verified through CE testing and say, “yeah, but that was in really cold water and at a ventilation rate that only an Olympian could maintain.” The ventilation rate of the diver in this video while using bailout was estimated to be over four times the rate that is tested by CE standards.

It is a terrible cascade when CO2 begins to elevate in the diver. Bailing out as soon as possible is critical or the cascade can lead to the point of unconsciousness… essentially suffocation by over ventilation as this diver experienced.

At some point, any scrubber design can be over-breathed. They all have their extreme limits.

This video is a terrific learning tool and I am grateful to the participating divers and manufacturer who realized it was more important to send a safety message to the community than to worry about the embarrassment of being a part of an incident. -- Jill Heinerth

Rebreather Divers: Take the Rubicon Survey

Jill Heinerth — Sun, 18 Dec 2011 06:22:57 PST

The Rubicon Foundation is compiling data for a study on carbon dioxide. Please take a few moments to help by filling out the attached survey. It is really quick and the results will be given at Rebreather 3.0 and in a post-conference publication for those that cannot attend.

Click here to go to the survey.