Introduction
It goes without saying that diving has inherent risks, even in its most basic and primitive state. The vast majority of people on this planet spend every day living and working on a two-dimensional plane. Gravity keeps them grounded, and photosynthesis provides a means to purify the air we all breathe, rid the atmosphere of carbon dioxide and providing us with the oxygen we need for our own metabolism. It’s easy to take this for granted when it’s all happening at such a grandiose scale. What if our scrubber (plants, trees, algae) failed? To take greater individual responsibility for planetary atmospheric management will require individuals to be forced to appreciate and bear the responsibility for personal atmospheric management. Underwater, while rebreather diving, this individual responsibility comes from sheer necessity, and therefore the well-versed rebreather diver is probably the best-informed educator and advocate for this atmospheric management responsibility. Climate change advocacy groups should be begging rebreather divers for their endorsements!
To dive safely, to any depth, requires self-discipline, responsibility, and an acute degree of self-awareness. For the duration of the excursion, we are freed from the two-dimensional plane but also stripped of the atmosphere that we take for granted. Diving in the shallows as a temporary visitor can be as simple as taking along compressed air and managing ‘how much’ we have left. Diving to extreme depths means extreme pressure and potentially dire impacts to our bodies’ physiology. Management of our breathing atmosphere, be it diving open-circuit SCUBA or closed-circuit devices, is life critical. This requires discipline.
Out on vertical walls, where I had my first calling to the deep, depth can be intimidating yet alluring. I recall my early experiences diving nitrox, where we are of course limited in depth by oxygen partial pressures. Hovering at 130 feet of seawater (fsw) at 1.6 bar pO2, it was a tease to stare down at thousands of feet of water. It was also dangerous, as it would be all too easy for a working scientist to drift to collect this or that and end up too deep. Yet, at the time, nitrox was the ticket for extending the duration of underwater forays for meaningful amounts of time that allowed the scientific work to take place.
Gas consumption remained an issue, though relieving the time pressure of required decompression did help to prolong our bottom times. By necessity, sets of double cylinders, then mixed-gas use, and thereafter rebreathers, were the obvious vehicles of choice to personally carry on with this scientific exploration along deep reefs in an incremental manner. At that time, rebreathers were even more taboo than they are today at this writing, and it took a monumental effort and fight to utilize this technology within the conventions of an academic and institutional setting. This point is a critical one – it set the tone for nearly my entire professional diving career – fighting the good fight to both advance and improve human intervention to advance scientific diving, and consequently by necessity the science of diving itself. Underscoring the battle – preserving the value of the human underwater.
My first exposure to closed circuit rebreathers was in 2002 when the Cousteau Society, then incubating a ‘Cousteau Advanced Diving Laboratory’ at the University of Rhode Island, loaned me a very early APD Inspiration Classic. It took only a couple of short hours of diving to immediately recognize the potential newly afforded to the working diver. No bubbles, longer no-decompression limits, warm/moist breathing gas, and virtually unlimited life support carried on one’s back, this very much seemed like the ticket to an improved human experience, and hence performance, underwater. At the same time, it shed light on how delicate a balance was played between the automated atmospheric management provided by the machine versus the degrees of change resulting from human inputs.
Shortly thereafter, I trained on a second system: the CCR2000. I recall meeting with Dan Wible, its inventor, in a Miami hotel room to review the unit before training. The hardware left me deeply impressed regarding its industrial build quality. I thought to myself, these two units are like apples and oranges. Once diving, however, and subsequently becoming trained on several additional rebreathers, what has become evident is that at the heart of it all, a rebreather is a rebreather is a rebreather’.
Each unit’s feature sets are a function of the inventor’s logic in solving both unique and perceived operational problems that impact the diver’s ability to manage a breathable atmosphere; however, in principle, the core technology is all fundamentally the same – breathe in and out of a bag, remove CO2, add oxygen. This fundamental concept has been at play since at least as far back as the 1800s. It’s not ‘new technology’ – what has progressed is know-how related to how we use it now, how it may be improved upon to better apply it in the future, and how we engrain related knowledge into baseline diving science.
The fact that nuanced feature sets beyond this very basic concept are so heavily dependent on personal experience speaks to the fact that we are only at our infant stages of applying the technology fully and further realizing the potential utility value for this technology across numerous markets – it’s not just a sport diving tool! We now must learn how to apply the technology within specific market segments, tailoring its configuration or feature sets to optimally perform and help us execute the required tasks in the given working environment. For this reason alone, attempts to ‘standardize’ rebreather performance criteria or even configurations in their entirety is a damaging and market-limiting endeavor.
I will expand on ‘standards’ throughout. No one configuration suits every environment and every task and individual or team diving style, nor will there ever be, so we should not attempt to box in this already niche community. More important is to educate and promote required know-how such that broader end-user populations can conceive of how to make use of the technology within their diving regimen routinely – there are plenty of tasks and environments that would benefit from applications of rebreathers, though missing is operational know-how in the hands of those deciding how to perform the work, and even permitting or facilitating the work to occur. So consequently, rebreathers remain viewed as too complex, and we [broadly] just don’t use them, at least within occupational settings. This is to great detriment from both a cost savings perspective, as well as a human performance perspective when considering the enormous gap to fill in conducting deeper science and critical interpretative observations [in the shallows] globally.
At the start of the mainstream rebreather community taking shape circa the mid to late 1990’s, the very few available units were about deep and/or cave [distance] efficiencies. This mainstream push became possible given advances in oxygen monitoring – we quickly accepted that ‘knowing your pO2’ was the number one rule and was a relatively easy thought extension from recent adoptions of nitrox. Rebreather technology has since been marketed in this vain – as a highly technical tool well suited for deep or cave diving. Many people aspire to dive rebreathers to achieve some personal exploration goal, and as I view it this type of aspiration marketed by the industry does not promote a complete understanding of the value of the technology.
Rather, people frequently end up on a path to move toward their goal as quickly as possible, often forgoing critical baseline knowledge. For example, rebreather training has fallen within the trap of the established recreational diving training paradigm – it is possible to become a ‘rebreather diver’ in about a week. But, what does that mean? After a week, one may know how to operate that rebreather, but this means very, very little. Knowledge and skills are perishable, emphasizing that proficiency regimens must be accounted for, and at that ideally while under some degree of mentorship so that bad habitats do not form and reactive manners of thinking become more and more refined. Collectively, this is all asking for quite a lot of someone – certainly more than is being offered with or is attainable from a purchased course of training.
Step back for a moment…consider the path we are set down with a basic open water course as everyone’s very first introduction to the underwater world. The shift from open circuit to closed circuit, when marketed in the vain of ambitions for deep or cave or otherwise technical diving may be a disservice. It results in small numbers, high costs, and much later career adoption than would allow a diving career trajectory that embraces the powerful capability as central to an evolving diving career over a lifetime. From a human intervention standpoint, this is problematic, as it leaves progress in the hands of only an elite few.
Rather, true progress will be from deeply embedded knowledge across a broad base. This can occur from ‘Day 1’ with a more fundamental presentation of atmospheric management at the open water level, and then enabling the diver to leverage this understanding when applied throughout all subsequent experiences. It may sound counterintuitive, to lower the threshold, though I believe it can be done with reimagined training that embraces new fundamental tenets – primarily enforcing that trainees must think like immersed blue planet citizens, not like temporary visitors.
Of course, several ‘big’ dives have been successful across both the spectrum of linear distance traveled (largely in caves) and depth, and it’s all important; however, still lacking is the routine utility of these big dives to get much of anything constructive done outside of achieving one’s personal motives or ambitions. In large part, what we dub ‘exploration dives’ are being performed by the diving enthusiast, not by scientists nor with scientific motivations to acquire data. This is due to bureaucratic restrictions, perceived liability issues, regulatory concerns, academic silos that prohibit productive collaborations outside of one’s small niche – and most importantly challenges in attaining and maintaining degrees of proficiency to perform the work for oneself. It is important to note here that ‘scientific motivations’ historically have been driven by scientists.
Emerging is a social shift that needs to be embraced and not fought – as more people venture underwater, particularly with capabilities that allow the environment to be viewed and interpreted in a novel way, each intervention becomes a data-gathering opportunity. Simply – ‘if you see something, say something’. Ask questions, and search for answers – every single person experiencing the underwater environment without bubbles, and for more than an hour or so at a time has a very high probability of making observations that reveal something new to science altogether. That’s a huge opportunity, and we [broadly] need to capitalize on this concept. Imagine an entire new generation of young divers experiencing the silent world, silently…it very much changes our interpretation of the watery world around us which is, well - everything.
Communally, I believe we’d benefit from stepping back – way back. Instead of aspiring to deepness, let’s promote understanding the technology and embed that body of knowledge within every diver – every single one – from ‘Day 1’. Again, principles in atmospheric management are something we should be learning about in high school, or perhaps even earlier. Taking that bite of know-how decades before people typically get into rebreathers (mid-life/career) will push the entire community forward, rather than pull them, and encourage the curiosity and lines of critical thinking that we desperately need to even conceptualize science and exploration of deeper environments at the same scale that we’ve studied shallower environments for almost a century.
Absent this change in dive community social structure, I don’t believe it’s possible to understand more challenging environments at a broad scale – access cannot remain in the hands of the few elite, and we very desperately need people to ‘be there’ at a scale much larger than today if for nothing more than to bring home the stories through firsthand observations and experiential learning that keep inspiring future generations, and do indeed influence broad political decision making.
A slight segue, though worth mentioning, is that the recent industrialization of our continental shelf has been occurring largely blind – without any firsthand and personal observations of this environment’s natural history. The consequences of this industrial expansion will resonate for generations – a missed opportunity to date has been affording this human-ocean interaction before proceeding. A person cognizant of his/her surroundings while embedded in this or any environment would quickly become a compassionate advocate for its protection, rather than permitting it to be destroyed for profit. We need that capability prioritized and valued massively – we need to make diving important again.
Certainly, the continued demonstration of technological capacity at the elite level can inspire valuable new knowledge and remains a critical industry driver – exploration is important. However, this technological capacity has been a bit of a swing and a miss within the scientific community where large-scale academic investments have not been made into the technology itself nor required know-how, leaving open what should be a closed economic loop driving scientific advancement of both the technology and what can be done with it.
‘Closing the loop’, so to speak, where the academic sector embraces rebreathers as a technology platform rather than simply a commodity tool (like open circuit scuba) and begins making strategic investments to advance the technology is a critical bottleneck. By contrast and for example, underwater robotics has done a good job of this – academic institutions around the world work on all kinds of sensors, propulsion mechanisms, and data transfer technologies that motivate economic development in the commercial sector. We don’t really have that in diving, and it’s to the detriment of human intervention advancement - we won’t have it until rebreather technology is introduced early in the educational path, much like marine robotics being introduced to high school students – it’s a manner of thinking embedded in the social fabric of the community to fuel both academic and industrial advancement.
Needing to be unwound quite considerably is that all diving is often misperceived as simply picking up and going. It’s that notion that’s kept important advancements from occurring – the diving itself needs to be the priority (a vehicle) – missions with well planned and executed health and safety plans all keyed to the purpose at hand. This is a 180-degree manner of thinking to how diving for underwater science is approached today, where synergies between diving technologists and scientists must be formed, invested in, and put to work. This is true from the simplest of data acquisition in the shallows, to the most complex out on the continental shelf. The processes involved in safe execution must be newly appreciated. So, while we must revisit Rebreathers 101 and where this fits within the global regimen of the underwater experience, we must also revisit Dive Planning 101, as they go hand in hand. Following the discussion of design principles in this content, I present rebreather operations, and thereafter failure modes and their intervention. Portions of this must become buried within the new norm, much like basics of open circuit scuba, though new to the rebreather mindset are more acute (though not onerous or difficult) accident management considerations. This type of dive planning is critical, or as we say ‘mission critical’ – equipment selection must be keyed to dive plan requirements, rather than box in operational limitations given the available equipment.
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If I may rewind a bit to my tenure as Diving Safety Officer for NOAA’s Caribbean Marine Research Center on Lee Stocking Island in the early to mid-2000s; the science community was seemingly at the cusp of taking their work to new depths. There were numerous projects throughout the US NOAA Undersea Research Program all eyeing rebreather use to carry them forward. It was an exciting, but challenging time.
Despite the [sport] technical diving community embracing emerging techniques in mixed-gas and decompression diving, there were no standards of practice in place within scientific diving to make use of the best tools for the job at hand – there was no easy path without looking to the sports community for training, and that was not always well accepted. To put it all to work in several projects and programs, I was among those challenged to fight the fight amongst peers, insurance companies, lawyers, administrators, funders, and it goes on – and that was just to use existing tools, never mind develop new tools. These struggles should never have occurred, and in hindsight, they expose the deep issues in valuing human intervention as a critical contributor to our knowledge base.
The science community and the scientists who have had curiosities sparked about novel environments should have been complemented with the expertise to get there, rather than being presented with barriers to entry. While steady incremental progress has been made in addressing these types of issues on a per-program basis, missteps in attempting to standardize rebreathers for scientific use created an uphill battle prohibiting the science community from taking a leadership role in advanced diving itself. We need the ‘can-do’ spirit that is often mistakenly considered cavalier, though applied within a framework in which safe practices can be managed with accountability – that’s no easy task. These early projects were all faced with “can versus cannot” instead of “should or shouldn’t” decision-making, with the latter being more open-minded and facilitative rather than stifling. As of this ongoing editorial in 2025, the advancement of diving science itself is driven by enthusiasts’ personal curiosity and not on a scientific needs basis per se. A seminal question outstanding is whether there can be effective mechanisms that facilitate collaboration across these boundaries. Often, scientific diving programs tend to fall apart by overwriting standards, thinking that this is a positive contribution to risk mitigation – it is not. Overwriting standards create arbitrary barriers to entry, effectively paralyzing the ability to make progress. Other diving communities take a different approach altogether, with risk assessments guiding procedural development and adoption of appropriate technology or techniques to mitigate said risks of the specific task at hand.
For example, if a researcher requires data from XYZ deep environment, the immediate thought should not be ‘Oh, my dive program doesn’t support mixed-gas or rebreathers, therefore, I can’t train for and prepare to personally do the work’, but rather a good dive officer or program manager will say ‘let’s review the best technique to get there, understand the risks, and identify a path to achieve the work objective’. The latter approach creates opportunities and would result in academic-industry collaborations and partnerships. Complicating this within diving is that many researchers want to perform their own in-water work – it’s an exciting appeal to the field, though not practical in all instances as we look to deeper and more complex environments given training and proficiency requirements. In such instances, diving should be viewed as a vehicle, much like an ROV or submersible – a vehicle that affords the dexterity of the human hand, critical thinking, and spatial awareness to interpret the environment – though is also a vehicle that may need to be operated by experts who has maintained this training and proficiency requirement.
This human vehicle exists in commercial diving (human divers are tools in the toolbox to perform any number of tasks) already though there are challenges in strict diver-for-hire scenarios since it is often thought that scientific know-how is required to perform scientific tasks. This is not universally true and challenges the scientific exemption to US federal regulations for commercial diving. These will evolve, eventually, to better align with the current and newly emerging state of the art.
In commercial diving, where the [antiquated] OSHA Code of Federal Regulations trumps all (in the US), tried and true is also an incredibly difficult battle to argue against, even when there is reason to believe that a little bit of technology only makes the diver more productive and efficient (saving costs), is a quantum leap in protecting the human from the environment (improved safety), and lifts practical limitations of antiquated equipment or techniques (increased efficiency). We are still in need of considerable efforts placed on educating policymakers such that change can be massaged from the top down, just as we divers continue to trudge from the bottom up. In both scientific and industry sectors, the unwillingness and even at times inability to consider technology or techniques beyond accepted norms, or even merely acknowledged as a tool in the toolbox, is hugely problematic. The Marine Technology Society has been one organization developing a position on this very issue and moving forward with organizational policy that will create more community-wide opportunities.
Now moving forward, consider that perspective of time; with rebreathers starting to emerge in the mainstream in the early 2000s but quite likely taking until the 2050s to be used productively at any broad scale is frustrating for those of us with skin in the game, but also makes one appreciate that real change just takes time. Open-circuit SCUBA courtesy of Jacques Cousteau was similarly a multi-decade-long evolution. We should not overlook that rebreathers themselves have predated open-circuit scuba, with their first introduction in the mid-1800s, revealing their obvious benefits but also exposing just how complex a paradigm shift this may be to implement since it's not simply a technical problem – the social and cultural issues are very real.
Suffice it to say, advancing a human presence beneath the sea – for meaningful scientific gain - is a very, very long road. I’ve been fortunate to watch the change wheels start to turn a bit – my own career has aligned almost perfectly with the rebreather and technical diving communities taking shape - dives have become longer and deeper, but at the same time, the power of a little sixty to eighty-pound backpack is far from exhausted. Today, in 2025, diving in excess of 300 feet of depth and for cumulative dive times of four or more hours is reasonably achieved by anyone with the determination to have that experience – it’s not particularly difficult from a technique standpoint. Twenty years ago, it was a very big deal. The limits of rebreather technology are also far from being understood and reached.
Throughout this text, I hope to expose some of the technical and operational shortfalls that impose these limitations. In practice, a very little bit of innovation in these areas may make depths of 500 feet and cumulative dive times of 5 hours (call it 500 for 5) the new ’60 for 60’ which has well defined our rule of thumb for shallow air diving using SCUBA for the last three-quarters of a century.
The beauty of human intervention is having the diversity of humans underwater, at depth, and bringing each of their unique experiential perspectives back to the community to share and to learn from. Advanced and rebreather diving can be more broadly commoditized from the perspective of embedded know-how, though certain elements related to risk assessments and project management should be centralized to reduce the liabilities of those who stand to benefit from the acquired knowledge and data. That means standardizing certain aspects of diving operations that are mission-oriented, particularly when performed on behalf of a client. The ‘S’ word, or standards, has wavered substantially in recent years and has created substantial confusion – there are manufacturing standards, testing standards, training standards, and proficiency standards. All are obvious attempts to retain market share and control risk when this innovation is applied. Some of this is ok, but other elements are not at all ok.
A simple and matter-of-fact example of standardized but highly convoluted buffoonery is the requirement of certain alleged US regulatory authorities for the use of electronically controlled rebreather systems exclusively - manual systems are a ‘no-no’. However, some of the most forward-looking private explorations are done using manual systems with a sound track record of success and productivity.
Rhetorically, what is the good reason for limiting the advancement of science, and the science of the technology itself, by imposing standardized life support that may or may not meet all the demands today and into the future? That train of thought and decision-making does one thing – it thwarts progress [and probably puts money in someone’s pocket]. Rather, we need divers to be critical thinkers much like social scientists - capable of recognizing risks, troubleshooting, and ultimately choosing the best tool for the job. Ironically, the scientific method is not embraced in advancing technology and techniques required of the very underwater science we are striving to execute.
So, Houston, we have a problem – progress is being made outside of the control of the institution and the bureaucracy, and the institution is struggling to keep up and is therefore poised to fail or at least continue to fall behind – critical science is not being conducted, information is being lost, and people’s roles and capabilities beneath the sea are not being capitalized upon to their fullest extent. Instead, industry is doing everything possible to take people out of the equation – at the expense of billions and billions of dollars invested into robotics and sensors. The cost to us, people, is immeasurable – we end up losing the human perspective of being there, and consequently big policy decisions are made without this added value…the human element - compassion for the environment. This is a major deficiency and an expanding societal handicap. People are needed to inspire people [to make good decisions and do the right thing].
So, Why Write This Manuscript?
OK, now I’ve straddled two issues that may appear confused – rebreathers and underwater science – though they are indeed critically dependent upon one another for either or both to meaningfully advance. So…a toe dip into my motivations - why write this content? This book took shape after compiling over twenty years of practical experience focusing on the challenge of developing safe, effective, and intuitive methods for using closed circuit rebreathers more routinely for work – all with an eye on the resulting more meaningful scientific data acquisition, and at broadly sweeping scales. The content acutely reflects rebreather subsystems, their configuration, and utility as we’re assuming that this diving modality has been, to date, the logical technology to allow a new planar view of underwater inquisition. That may or may not be the case for the long haul, which I’ll touch on elsewhere in this manuscript.
I realize full well that not every element described in this content carries over to all underwater environments; however, believe that this work is unique in that the lessons learned may encourage a certain manner of thinking that sheds light on how we work, innovate, and further explore current environments, or even environments yet to be discovered – by removing guesswork and making atmospheric management easy, or at least much better understood as it applies to our personal management of life support while diving. Interestingly, it’s been the gross simplification of rebreathers to make them useful ‘in the mud’, quite literally, that has steered many of the principles herein.
This is not a textbook or training manual. In fact, I’ve struggled immensely with the proper conduit and format to publish the enclosed material (popular articles, white papers, training texts, etc.). Frankly, yes, though inherently technical in nature, this literary work is full of opinions though formed through practical experience, as any body of work must start somewhere. All the enclosed content is grounded in personal experience and self-study and an incremental approach to innovation in life support integration and functional design. This is the stuff I only wished was handed to me when I was 18 years old in some well-referenced, easy operations manual, as it would have saved me years of struggle, expense, and self-study. In hindsight, however, I suppose if it had already been done, I would have been bored and on to something else.
As I’ve put various rebreather systems to work, it has become necessary to modify systems for various reasons – to improve out-of-the-box operations, to simply ‘fit’ into a confined space, to enhance performance, to permit an end-user operation previously not supported, and even extend range capabilities to multiple days. These types of modifications are undertaken by nearly all of those who use closed circuit rebreathers; a testament to both the art and science of this technology offering a massive opportunity ahead should we adopt a widespread open-sourced approach to educating about and utilizing the technology [rather than educate or train for a specific system].
In working through my personal system(s) for niche scientific exploration and other working applications, I made the effort to collate and assemble documentation supporting my system rationale and the logic that influenced the modifications made. As time has passed, my ‘technology platform’ has evolved considerably, so much so that the rebreather I now dive is a 100% custom system and has itself created several commercial opportunities for both product development and services offered. This content references the path journeyed to evolve several Principles of Design, intended to guide a best-of-breed approach to life support design that comes from critical thinking, logical deduction, and problem-solving. While the resultant material herein reflects my storied experiences and lessons learned, it is this level of logic that is an absolute must when transitioning into and adopting rebreather use more routinely. Every developer of rebreather systems or components should have a similar rationale and design principles that have guided their own work. For you, as the diver, it's critically important to align with principles you agree with, fully understand, and can rationalize when applied within the scope of work and nature of dives you undertake. One size will never fit all, and this fact compounds the issue of wider spread rebreather adoption.
The critical bottleneck with this concept of leveraging rebreather technology as an organic and modifiable platform is the limited availability of information, and more importantly, delivering this information where it’s most needed – early early early.
My motivations in writing this content are to offer an open-source solution if you will, that is intended to encourage a better understanding of rebreathers in general, and if implemented as an early and essential body of academic knowledge [think high school level], it will help provide some of the building blocks to move everything forward. Not all will agree with the information in this book, and that’s perfectly ok.
Admittedly, some areas are incomplete and may even reveal potentially flawed assumptions on my part. Ongoing research in the area is most certainly needed, and why I consider diving itself an academic field of study, and why we’d all benefit from broadly embedding the science of diving throughout society and culture (even and especially among non-divers endeavoring to tackle underwater problems). Throughout, I make the effort to highlight where future research investments are indeed warranted. Content will be timestamped as this manuscript may evolve to reference new research as it becomes available.
Considering that much of this work took place on the heels of US Federal and state-funded programs (perhaps at times to their dismay), as a courtesy, I had initially forgone capitalization from a traditional business sense in trying to manufacture and sell hardware, and first put this work out there in the public domain for all to benefit. Since the first 2019 publication, demand for rebreather subsystems and components has steadily increased within niche markets, and in many cases components or features were still not available. In response to this need, together with partners, I have brought components embodying my design principles to market with a simplified production unit called Rebreather Day 1 ® (RD1). The overall design and system logic are being left largely open-sourced, as they should be…there’s nothing overly proprietary about 200+-year-old technology - we just need to think about its utility differently and understand its design logic as we apply it for the given task at hand. The open-sourced concepts in this content are presented while using our Rebreather Day 1® (RD1) subsystems and components as a working model, though everything described in this content makes/model agnostic and can equally apply or at least should be considered when studying to determine if one’s rebreather choices align with personally desired features, and common sense. Given the use of the RD1 as a model system, this work may then be considered the unofficially official companion guide to the RD1.
Accepting that rebreathers themselves solve a myriad of open circuit challenges, there then become new challenges though also opportunities. With deep rebreather diving specifically, a foremost challenge is lengthy and exhaustive decompression requirements. So long as humans are immersed and under pressure, this can’t be avoided; however, we can take steps to mitigate the risks of lengthy exposures and facilitate productive time spent while decompressing. My group first tackled this in 2012 with the introduction of a portable inflatable habitat into the diving regimen. While this presents engineering challenges of its own, what became immediately obvious is that a lightweight portable habitat can be viewed as a dependent component of diving life support, meaning the full capability of a rebreather can actually be utilized before making use of the habitat which itself has an atmosphere also managed with a rebreather!
Now, imagine using the convention of 4-6 hours afforded by a rebreather on one’s back for meaningful work, then the required additional time decompressing in relative comfort, all while self-contained. In my opinion, this could mark the start of a shifted paradigm where surface-to-surface forays with 4-6 hours of dive time are only the beginning, and days or more underwater can become within reach of the progressive and experienced technical diving community. ‘Near’ saturation diving, for the masses, may be at our fingertips, and is a critical evolution of the technical diving paradigm. In the not-so-distant future, thanks to rebreathers, that 500 for 5 may only be a toe-dip, and at the other end of the spectrum (in the shallows), 60 (feet) for 600 (minutes) starts becoming a reality – without ‘saturating’ and all the complexities that come with it. Whoa.
While considering this direction – of eyeing maximized personal life support usage - embedding this type of know-how within an academic context would promote a renewed manner of thinking, bring new capabilities forward, and expose hugely untapped scientific opportunities both in marine science and technology to take us there. Applied in that context, this book is just a small part of a push ahead.