Connect with us


Open Circuit Technical Diving Is Not Dead



by Richard Taylor. Images courtesy of Rob Wilson unless noted.

Hindsight can be sobering. Eight years ago, I argued open circuit (OC) technical training was becoming obsolete because of the push toward closed circuit rebreathers. Turns out, I was a bit aspirational, and wrong. We’re still not there—not even close. And maybe we will never be. 

A version of the piece, “Is There Still A Case for Open Circuit in Tech,” was first published in X-Ray Mag #70 in 2015, back when the question—Is Open Circuit Technical Diving Dead?— was about whether the push toward rebreathers would mean the end of OC training. Now, with rebreathers (CCRs) seemingly even more ubiquitous in technical diving, the question about whether there’s a place for open circuit at all is even more pertinent. 

Ask a CCR diver (a passionate bunch, to say the least) and they’ll likely dismiss the need for open circuit technical training. Many divers are swayed by the potential deep dive cost benefits, often brought on from CCR divers highlighting gas costs, longer bottom times and shorter deco. But most CCRs are not yet at the stage of CCR redundancy, and OC skills remain the primary backup for these divers. 

Some experienced CCR divers are arguing against the need for such training, even though they have likely had extensive OC training themselves, on which they will be able to lean if their rebreather fails and they have to bail out. Simply put, these experienced divers are asking new divers to take a risk they don’t have to take themselves.

As such, open circuit still has an important place in technical diving. Not only is OC technical diving alive and thriving in some areas, but we need to consider that OC technical training should be mandatory for all technical divers, even those diving on CCR. 

Where are We Heading?

Eight years ago, I wrote the following in a previous version of this article (edited for clarity):

“Excluding global disaster, you have to say that the CCRs are here to stay, and will only become more entrenched. More CCR manufacturers will enter the market with a resultant drop in prices as competition increases. The move to “Recreational” CCRs will increase as both established and new CCR manufacturers see this as a profitable share of the market, resulting in more retailers investing in this area to increase their own sales. 

As the recreational CCR market builds and unit price drops more divers will move along the CCR pathway. Divers will be drawn to CCR Training sooner and CCR Programs will become less reliant on any OC prerequisite. 

Of course, the rate at which this will occur will depend upon many forces, some internal in diving, some external. However, one thing is certain, CCRs are probably not going to go away.”

In eight years, not much has changed—except that the CCR lobby has grown even louder. As we continue to see a greater focus from the industry on CCR, we are seeing a need for easier unit crossovers, and potentially even a need for basic unit standardisation. But, along with this, we are also seeing a decline in OC skills for CCR divers. 

CCR hype has reached a crescendo. New CCR models are being introduced regularly (25+ mainstream agency recognised units at last count) with multiple tech units, “Type R” (recreational) and semi-closed and closed circuit variants for specific needs. We now have a European Rebreather Standard (EN14143) and RESA, the Rebreather Equipment & Safety Association.

Alongside this, the training agencies have pursued CCR divers with their usual commercial vigour, and there is a well-worn pathway allowing divers to develop along the technical side on CCR, often with little, if any, requirement for OC tech qualifications. Today’s aspiring technical diver Can be CCR trained with nothing more than four open circuit dives as an open water scuba diver.

CCR Training Alone Is Not Sufficient

In looking at current programs, CCR training courses need to include a stronger focus on core OC options such as OC gas consumption rates and dive planning. OC technical skills should be regarded as a mainstay of CCR diving as pretty much every CCR course still teaches bailout to open circuit. 

Many CCR divers, sadly, often portray OC tech diving as obsolete, like needing to learn how to drive a manual stick shift when you get your driver’s license. In other words, just learn in an automatic. They say that if you dive CCR, you learn how to plan an OC bailout, and that it makes more economic sense to just go CCR from the beginning. 

Lauren Fanning in Upstream Emerald Sink holding a line arrow from former WKPP director George Irvine. Photo by Kirill Egorov.
Lauren Fanning in Upstream Emerald Sink holding a line arrow from former WKPP director George Irvine. Photo by Kirill Egorov.

But keep in mind, virtually all of the divers making that argument still have OC training to fall back on in an emergency but it remains to be seen how the lack of that training will affect up-and-coming CCR divers. After all, how many CCR divers actually have a bailout CCR? 

OC Tech Training Remains Relevant

If we look at most current CCR training courses, there appears to be a need to include a stronger focus on core OC options such as OC gas consumption rates and dive planning. OC technical skills should be regarded as a mainstay of CCR diving as pretty much every CCR course still teaches bailout to open circuit.

Let’s not forget the size of the OC and OC technical market. Significant, upfront investment, access to training, rebreather support and services are critical to becoming a successful CCR diver. I don’t know if anyone has done a study on the untapped or latent technical diving market size, but I can use SDI/TDI President of International Training Brian Carney’s 2016 DEMA presentation on “How Big is the Technical Diving Market?” His data indicated that the ratio of OC tech vs. CCR tech was roughly 6:1. There are six OC tech divers to every CCR diver!

We must also recognize the inherent privilege embedded in the question about whether OC tech diving is dead. Diving isn’t a cheap sport by any means, but most divers don’t have the luxury of being able to buy a rebreather and support its ongoing costs and maintenance. CCRs might over time lessen the costs of tech diving, but not before a diver forks over what amounts to a year of college tuition for the unit and training. So maybe the CCR divers who are calling for the end of OC tech need to consider their own CCR privilege.

In time, CCRs may well dominate resorts, boats, and diving operations around the world, and there may emerge another bailout option for CCR divers i.e., rebreather bailout. 

But until that time comes, OC will be the “go to” option, and if we allow our CCR divers to progress through tech without sufficient OC skills, we are not only doing them an injustice but ourselves. There are currently about 20 CCR Fatalities each year (pre COVID). It is when things go wrong that we often say to ourselves, “If only I’d done or said that.”

Enjoying InDEPTH? Consider buying us a coffee so we can continue to provide you with insanely great content!

We began the discussion on OC vs CCR here (June):

Will Open Circuit Tech Diving Go the Way of the Dinosaurs? By Neal Pollock

GUE and the Future of Open Circuit Tech Diving By Ashley Stewart

Is deep, open circuit tech diving destined to share the fate of the spinosaurus? Complete our short survey: OC v CCR to find out.

One response to “Open Circuit Technical Diving Is Not Dead”

  1. We invite you to comment. 🤓

Leave a Reply

Your email address will not be published.


X-Ray Mag: Is There Still A Case for Open Circuit in Tech by Richard Taylor (2015)

DIVER mag: Rise of the Recreational Rebreather by Michael Menduno (2014)

TDI Blog: How Big is the Technical Diving Market? by Brian Carney

Technical Diving Instructor Trainer, Co-founder of TDI & SDI in Australia & NZ, and OZTeK Founder Richard Taylor may not be a diving dinosaur, but he has been around long enough to remember some of them!

Richard has over 30 years’ experience in technical diving (25 as an IT) including some of the first trimix dives in Australia in 1994 (before certifications were available). He was Regional Director for TDI/SDI Australia/NZ for over 15 years and founded or was part of many early technical diving projects in the region. He also founded & ran the acclaimed OZTeK Conferences from 1999 to 2007. 

Richard has taught hundreds of technical divers and Instructors around the world and continues to teach today for SDI/TDI/FRTI and is one of the few Instructor Trainer Evaluators.

He is not afraid of voicing a strong view on subjects and, as a past rebreather diver & instructor, is a passionate advocate for training and maintaining open circuit technical diving skills. His strong belief is that as we gain more experience we gain a responsibility to pass our knowledge and skills on to others so that those who come after us can go further than we have, and come back and tell us their story!

1 Comment

1 Comment

Leave a Reply

Your email address will not be published.


The Price of Helium is Up in the Air

With helium prices on the rise, and limited or no availability in some regions, we decided to conduct a survey of global GUE instructors and dive centers to get a reading on their pain thresholds. We feel your pain—especially you OC divers! InDEPTH editor Ashley Stewart then reached out to the helium industry’s go-to-guy Phil Kornbluth for a prognosis. Here’s what we found out.




Helium Technical Diving

By Ashley Stewart. Header image by SJ Alice Bennett.

Helium is one of the most abundant elements in the universe, but here on Earth, it’s the only element considered a nonrenewable resource. The colorless, odorless, and tasteless inert gas is generated deep underground through the natural radioactive decay of elements such as uranium and thorium in a process that takes many millennia. Once it reaches the Earth’s surface, helium is quickly released into the atmosphere—where it’s deemed too expensive to recover—and rises until it ultimately escapes into outer space. 

Luckily for divers who rely on the non-narcotic and lightweight gas for deep diving (not to mention anyone who needs an MRI scan or who uses virtually any electronic device), some helium mixes with natural gas underground and can be recovered through drilling and refinement.

Yet the world’s helium supply depends primarily on just 15 liquid helium production facilities around the globe, making the industry uniquely prone to supply chain disruptions, which this year caused the industry’s fourth prolonged shortage since 2006. The shortage has caused many technical dive shops around the world to raise prices, limit fills, or stop selling trimix altogether, according to an InDEPTH survey of GUE instructors and affiliated dive centers.

Longtime helium industry consultant Phil Kornbluth, however, expects the shortage will begin to ease gradually now through the end of the year, and for supply to increase significantly in the future.

Photo courtesy of Extreme Exposure

While a majority of the world’s helium is produced in just a few countries, a new gas processing plant in Siberia is expected to produce as much as 60 million cubic meters of helium per year, about as much as the US—the world’s largest helium producer—was able to produce in 2020. The Siberian plant ran for three weeks in September, but experienced major disruptions over the past year, including a fire in October and an explosion in January, that delayed its planned opening until at least 2023.

Meanwhile, according to Kornbluth, the U.S. Bureau of Land Management in Texas closed down from mid-January to early June due to safety, staff, and equipment issues, wiping out at least 10% of the market supply. The plant reopened in June and is back to normal production as of July 10. The supply of helium was further reduced as two of Qatar’s three plants closed down for planned maintenance, a fire paused production at a plant in Kansas, and the war in Ukraine reduced production of one Algerian plant.

With the exception of the plant in Siberia, Kornbluth said virtually all of the recent disruptions to the helium supply chain have been resolved and should yield some relief. And the future looks promising. Once the Siberian plant is online, it’s expected to eventually boost the world’s helium supply by one-third. While sanctions against Russia could prevent some buyers from purchasing the country’s helium, Kornbluth expects there will be plenty of demand from countries that as of now are not participating, like China, Korea, Taiwan, and India, though there could be delays if those countries have to purchase the expensive, specialized cryogenic containers required to transport bulk liquid helium. “Sanctions are unlikely to keep the helium out of the market,” Kornbluth said.

Meanwhile, there are at least 30 startup companies exploring for helium, and there are other projects in the pipeline including in the U.S., Canada, Qatar, Tanzania, and South Africa. “Yes, we’re in a shortage and, yes, it’s been pretty bad, but it should start improving,” Kornbluth told InDEPTH. “The world is not running out of helium anytime soon.” 


To find out how the helium shortage is affecting divers, InDEPTH surveyed Global Underwater Explorers’ (GUE) instructors and dive centers and received 40 responses from around the world. 

The survey’s highest reported helium price was in Bonaire—a Dutch island in the Caribbean that imports its helium from the Netherlands—where helium costs as much as US$0.14 Liter(L)/$4.00 cubic foot (cf) and is expected to rise. At that price, a set of trimix 18/45 (18% O2, 45% He) in double HP100s (similar to D12s) would cost around $360.00 and trimix 15/55 would cost $440.00.

“We have enough to support both open circuit and CCR, but in the near future, if the situation remains, we may be forced to supply only CCR divers,” Bonaire-based GUE instructor German “Mr. G.” Arango told InDEPTH. “We have enough for 2022, but 2023 is hard to predict.”

Not far behind Bonaire was the Philippines, where helium costs around US$0.13 L/$3.68 cf—if you can even get it. Based on the responses to our survey, Asia is experiencing the greatest shortages. Supply is unavailable in some parts of the Philippines, limited in South Korea, and unavailable for diving purposes in Japan as suppliers are prioritizing helium in the country for medical uses, according to four instructors from the region. In Australia, it’s relatively easy to obtain.

Four US-based instructors reported that helium prices are increasing significantly and supply is decreasing. Helium remains “very limited” in Florida and prices in Seattle increased to $2.50 from $1.50 per cubic foot ($0.09 L from about $0.05 L) in the past six months, and there was a period when the region couldn’t get helium as suppliers were prioritizing medical uses. In Los Angeles, prices have reached as high as $2.80 cf (nearly $0.10 L) and one instructor reported helium is only available for hospitals and medical purposes, even for long-term gas company clients who are grandfathered in. Another Los Angeles-based instructor said direct purchases of helium had been limited to one T bottle per month, down from three. 

“Currently, we are only providing trimix fills for our CCR communities,” GUE instructor Steven Millington said. “Possibly this will change, but the current direction for active technical divers is CCR. I agree (and already see) that open circuit technical diving in some regions will go the way of the dinosaur.”

In Western Europe, helium is becoming more difficult and expensive to acquire, 10 instructors in the region told us. Instructors in the United Kingdom, Spain, Italy, and Germany reported longer wait times, high price increases, and limited supply. 

Meanwhile, Northern Europe appears to be a bright spot on the map with comparatively reasonable prices and general availability. In Norway, two instructors reported helium is easy to obtain, with no lead time from suppliers. Likewise in Sweden and Finland, though one Finnish instructor told us that in the past year prices have increased significantly.

Three instructors in Northern Africa and the Middle East said helium is easy to get, but is becoming more expensive. The price of Sofnolime used in rebreathers is increasing in Egypt as helium becomes more expensive and more difficult to obtain. Lebanon has minimal lead times, but helium is among the most expensive in all of the responses we received at US$0.10 L/$2.83 cf.

Helium is generally easy to obtain in Mexico, though prices are increasing dramatically and instructors are starting to see delays. In Brazil, prices in São Paulo quadrupled in the past 12 months and by 30% in Curitiba. Suppliers there aren’t accepting new customers and existing customers are having difficulty obtaining supply. Supply is mostly constrained in Canada, with the exception of one outlier: an instructor who has a longstanding account with the gas company and pays less than US$ 0.035 L/$1.00 cf. “I have been hearing of helium shortage every year for the last decade,” instructor Michael Pinault of Brockville Ontario told InDEPTH, “but I have never not been able to purchase it.”

Many instructors around the world said that helium shortages and skyrocketing prices are, no surprise, fueling a shift to CCR for individual divers and exploration projects. “CCR is saving our exploration projects,” GUE instructor Mario Arena, who runs exploration projects in Europe, said. “These projects would be impossible without it.”

Please let us know what helium prices and availability are in your area: InDEPTH Reader Helium survey

Additional Resources

US Geological Survey: Helium Data Sheet: Mineral Commodity Summaries 2021

NPR: The World Is Constantly Running Out Of Helium. Here’s Why It Matters (2019)

The Diver Medic: The Future of Helium is Up in the Air,” Everything you wanted to know about helium, but were too busy analyzing your gas to ask—talk by InDEPTH chief Michael Menduno

InDepth Managing Editor Ashley Stewart is a Seattle-based journalist and tech diver. Ashley started diving with Global Underwater Explorers and writing for InDepth in 2021. She is a GUE Tech 2 and CCR1 diver and on her way to becoming an instructor. In her day job, Ashley is an investigative journalist reporting on technology companies. She can be reached at:

Enjoying InDEPTH? Consider buying us a coffee so we can continue to provide you with insanely great content!

Continue Reading

Thank You to Our Sponsors


Education, Conservation, and Exploration articles for the diving obsessed. Subscribe to our monthly blog and get our latest stories and content delivered to your inbox every Thursday.

Latest Features