Closed Circuit | Open Sourced– Lombardi Undersea

the fine print

Closed Circuit | Open Sourced second edition the unofficially official companion book to the Rebreather Day 1 ® System, Components, and Meth...

Preface

Preface This has been my most challenging text to write. Over the years and across scores of writing I have indeed done - grant proposals, operatio...

Foreword

Foreword This content is the closed-circuit rebreather diving and design philosophy of one man who for two decades (as of this initial 2019 public...

Introduction

Introduction It goes without saying that diving has inherent risks, even in its most basic and primitive state. The vast majority of people on t...

1.0 Tenets of the Rebreather Envelope and Principles of Design

To leverage rebreathers, broadly, as a platform that may push forward our relationship with this Blue Planet, there are several basic tenets that r...

-1.1 Chassis and Fundamental Configuration

1.1 Chassis & Fundamental Configuration The basic envelope and fundamental configuration of any rebreather device includes several simple pr...

-1.2 Breathing Loop

1.2 Breathing Loop The breathing loop consists of subassemblies for the mouthpiece (Dive Surface Valve (DSV) or Bailout Valve (BOV)), breathing ...

-1.3 Carbon Dioxide Removal

1.3 Carbon Dioxide Removal The carbon dioxide removal system, or scrubber, is the heart of a rebreather device. Proper use of the scrubber require...

-1.4 Gas Distribution

1.4 Gas Distribution Catastrophic loss of high-pressure gases is a very minimal risk; however, failure of low-pressure gas delivery devices should ...

--1.41 Diluent Side Gas Distribution Components and Functions

1.41 Diluent Side Gas Distribution Components and Functions The high-pressure diluent gas is regulated to 125-150 psi (typical first stage regulato...

--1.42 Oxygen Side Gas Distribution Components and Functions

1.42 Oxygen Side Gas Distribution Components and Functions The onboard oxygen supply is also an AL13 (AA 2L) cylinder containing medical or aviator...

--1.43 System Compatibility for Gas Sharing

1.43 System Compatibility for Gas Sharing As the population of rebreather divers has grown, there's been a few divergent paths evolved on gas flow ...

--1.44 Points of Gas Injection

1.44 Points of Gas Injection Gas is introduced into the breathing loop often at the ‘head’ of the rebreather, which should provide porting options...

--1.45 Color Coordination

1.45 Color Coordination If making custom whips, hose assemblies, and cylinder markings, it is useful to use color codes that are consistent through...

-1.5 Oxygen Monitoring

1.5 Oxygen Monitoring At this writing, we seem to be on the eve of a new paradigm in oxygen monitoring via solid-state (IR) oxygen sensor technol...

2.0 Operations

2.0 Operations The aforementioned design principles have been discovered through understanding ‘what we dive’ in practice. Through organizing th...

-2.1 Pre-Dive Checklist, H.A.P.P.Y.

2.1 Pre-Dive Checklist, H.A.P.P.Y While the mechanics of a checklist can vary slightly from system to system, the following simple mnemonic prov...

-2.2 Operations During the Dive

2.2 Operations During the Dive Dive Planning & Staging Logic This text is not intended as a replacement for proper closed circuit rebreather...

-2.3 Post-Dive

2.3 Post-Dive Upon surfacing, pO2 must be maintained until the diver has doffed the face mask, helmet, and/or removed the /DSVBOV from his mouth...

-2.4 Maintenance

2.4 Maintenance Maintenance should be performed at regular and routine intervals. These items should not be confused with a thorough pre-dive c...

3.0 Understanding Failure Modes and Intervention

3.0 Understanding Failure Modes & Intervention When all subsystems of a rebreather function properly, very little diver intervention is requ...

-3.1 Atmospheric Management 101

3.1 Atmospheric Management 101 While we’ve focused considerable attention on hardware and the mechanics of such hardware, inherent to rebreather d...

-3.2 The Triple H's

3.2 The Triple H’s Noticeable fluctuations within the breathing loop gas composition can be defined by the Triple H’s: hypoxia, hyperoxia, and hyp...

-3.3 Activity Hazard Analyses (AHAs)

3.3 Activity Hazard Analyses (AHAs) The following charts reference activity hazards associated with general closed circuit rebreather diving, cou...

-3.4 Omitted Decompression

3.4 Omitted Decompression Among the challenges with very lengthy decompression diving is that everything can go to plan, until it doesn’t. It’s ...

4.0 Design/Build Examples

4.0 Design/Build Examples The beauty in the art of innovation is that the power of knowledge gathered over time allows for informed decisions mo...

-4.1 RD1 (Rebreather Day 1)

4.1 RD1 (Rebreather Day 1) I was admittedly at a bit of a slump as a working diver in the summer of 2018. The diving seemed to dry up. The phone ...

-4.2 Ocean Space Habitat

4.2 Ocean Space Habitat Decompression. It’s the hard reality faced that comes with human exposure to pressure, and the challenge we divers have ...

-4.3 Helmet Integration (REDLINE)

4.3 Helmet Integration (REDLINE) Building upon the earlier work for what became the RD1 components and systems available to consumers, I began to ...

5.0 Training

Rebreather training has been a contested subject in recent years, in part due to the technology representing a convergence of varying industry sect...

Epilogue

Epilogue At some point along the way, the perplexities of everyone else’s logic resulted in my decision to give it a go for myself. Why bother? ...

Appendix 1 | Useful Forms

Appendix 1 | Useful Forms The following sample forms are intended as supplemental information for dive planning and operations. These do not rep...

Appendix 2 | Notes on Fittings, Glands, and Hoses

Appendix 2 | Some Parts & Pieces I have intentionally shied away from providing very specific component specifications throughout this conte...

Appendix 3 | Basic Hand Signal Guide

Appendix 3 | Basic Hand Signal Guide This appendix is purely a bonus since I haven’t been able to publish it anywhere else. I originally organiz...

Appendix 4 | Understanding and Accepting Risk

Appendix 4 | Understanding and Accepting Risk Well, it's all relative... Cause of Death Lifetime Odds Heart Disea...

References

References The below reference materials have all been drawn from in researching and preparing the enclosed content. While not all are cited wit...