5 Best Rebreathers in 2023

If you’re interested in a rebreather (including closed and semi-closed systems), you’ve certainly been a scuba diver for some time. The increased depth and bottom time can really take your diving experiences to a whole new level. It opens up different kinds of dive sites that are beyond open-circuit scuba.

A rebreather is often employed by technical divers, including photographers and marine archaeologists, etc., and sometimes at shallower depths.

All the added benefits of rebreather diving come at a cost — for the unit itself, for consumables such as sorb (soda lime), and for any extra training you need. So it’s safe to say that buying an expensive rebreather isn’t something a diver should take lightly. You want to get a unit that’s right for you and your intended diving the first time around.

Let’s take a closer look at five of the top rebreathers on the market in 2023. Read our guide below for tips and things to consider.

Things to consider before buying a rebreather

With that in mind, before diving into the top rebreathers on the market in 2023, let’s take a closer look at the things you should consider before buying a rebreather.

Whether you’re currently researching your first rebreather or you’re changing to a new unit, there are a few things you’ll need to think about. Not all of these considerations apply to all divers, but we’ve tried to cover some essential bases.

Are you experienced enough for rebreather diving?

In 2013, Dr. Andrew Fock, a hyperbaric specialist at the Albert Hospital in Melbourne, Australia, released a paper on deaths in the rebreather diver community. After analyzing data from 1998 to 2010, Dr. Fock concluded that rebreather diving was ten times more dangerous than open-circuit scuba. He also noted that most incidents were a result of “pilot error.”

We quote this statistic not to scare you off rebreathers, but to remind rebreather divers-to-be that you should have the training and dive experience needed to dive with these units. Ideally, you have a working understanding of the science of diving and excellent diving skills. As Jill Heinerth puts it: “This is not a time to be struggling with academic knowledge or diving skills.”

Do you understand the basics of rebreather diving?

Before you can even begin comparing rebreather units, you need to understand the fundamentals of rebreather diving. Learn more about standard rebreather components including what they do and how each part works.

Familiarize yourself with the different options and the differences. For example, you should know how radial and axial scrubbers vary, the key differences between back-mount and chest-mount counter lungs, the relative pros and cons of bailout valves or BOVs (also called OCBs) and DSVs, and other key matters.

If all the acronyms have your head spinning or you lack a rudimentary understanding of these terms, you’ll need to investigate further or get some training.

We recommend The Basics of Rebreather Diving by Jill Heinerth, cave explorer extraordinaire, to get you started.

In addition, Rebreathers Simplified, a 140-plus page guide to choosing a unit, will be helpful to new rebreather divers. Another commonly recommended book is Mastering Rebreathers by Jeff Bozanic, but be aware that this is now more than 20 years old.

We get it. You’d rather go diving than study, right? But if you’re paying more than US$10,000 for a rebreather, it only makes sense to know what you’re buying and how it operates.

Who will train me?

Before you purchase a unit, it makes sense to think about who will train you to use it! Find an instructor who has experience with the unit you’re considering. Ideally, they’ll know all the ins and outs of a model and can pass this insider information on to you.

Understand that you may need to travel to your instructor, so factor in travel costs in addition to training fees. It’s not smart to settle for second best when it comes to your rebreather education, choose a respected instructor with plenty of experience. You may find that their schedules are busy, so be prepared to book well in advance.

What is the rebreather CE 14143?

In Europe, all rebreathers must meet a strict set of standards. The CE 14143 compliance rating shows that a unit has obtained the standards required for safe operation. Factors examined during the certification process include a unit’s work of breather, sensor tracking functions, and other key elements.

In the US, however, these requirements are not mandatory. Nevertheless, many manufacturers choose to make CE-compliant rebreathers. When you choose a unit, it’s always smart to go with one that has been examined by a third-party regulating agency. Even if you live in the US, look for CE compliance in a rebreather.

Consider your budget, but don’t try to save too much!

As with most major purchases, your budget will, to an extent, dictate the unit you can purchase. But as the saying goes: “in for a penny, in for a pound.” It’s kind of similar with rebreathers because if you’re already spending around US$10,000 on a unit, an additional $200 can’t break an already broken bank!

Trying to save, and giving up functionality or features you want, could mean ending up with a unit that’s not right for you. And if that happens, you’ll probably sell the unit and buy what you should have bought in the first place!

Will you travel with your rebreather?

Rebreathers aren’t small pieces of kit, and some are more suited to travel than others. If you plan on taking your rebreather overseas, find out how easy it is to travel with a certain unit. Assess whether it can be broken down into parts that will fit inside bags or cases that match the airline’s size and weight requirements.

In addition, consider all the spare parts and accessories you’ll need to take with you. The list might be longer than you think. The Dirty Dozen Expeditions has an excellent packing-list resource for divers traveling with a CCR, you can find that list here.

Servicing matters

Rebreathers take a lot of ongoing care and maintenance. Ignoring minor (or what you think are minor) issues is not an option, and it could even lead to a major in-water issue. So be prepared to service your rebreather after 12 months of use or 15 months after the date of production.

With that in mind, it makes sense to choose a unit that you can have serviced in your home country, or close by, at least. There’s little point in buying a unit that can only be fixed in Europe, for example, if you’re based in the US. Before buying, find out where a given unit can be serviced.

SCR or CCR?

Semi-closed (SCR) and closed-circuit rebreathers (CCR) each have distinct advantages and disadvantages. Most SCRs are simpler, mechanical units that don’t rely heavily on O2 sensors or electronics. Many rebreather divers would argue that this means the chances of a failure are lower, and, should a failure occur, that it’s easier or more intuitive to remedy.

CCR units, on the other hand, generally rely on electronics and O2 sensors to adjust the diver’s breathing mixture. This means the diver receives a tailored breathing gas that’s perfectly suited to the diver’s depth and time. Because of this, CCR units are considered more flexible. The downside is that they’re more complex and certain failures aren’t easy to immediately diagnose and remedy.

CCR units can be either electronic (ECCR) or manual (MCCR). With the former, a computer constantly measures the oxygen percentage in the breathing loop and maintains an oxygen partial pressure (PPO2) set point. In contrast, MCCR units require input from the diver. He or she will need to monitor the oxygen percentage in the breathing loop and inject more as needed to maintain a set PPO2. This entails a higher level of diver diligence and awareness.

Some types of diving are better suited to CCR and others to SCR. Determine what kind of dives you’d like to do with your rebreather, talk to experts in that field and find out what their unit of choice is.

That all said, there’s an argument to be made that SCR units are becoming less popular, despite the efforts of some training agencies. We spoke to several top-level CCR divers, and each told us the same thing: most SCR divers become CCR divers within a few years. If you think the same thing might happen to you, consider skipping the SCR part and going directly to CCR.