CCR rebreather properties that you MUST evaluate before buying

„There is no perfect rebreather, but you can find the right rebreather for you if you are willing to do a little work.“
–Jill Heinerth – Canadian cave explorer, filmmaker and author in article „10 Things to Know Before Buying a Rebreather“, DIVER Magazine, 14. 1. 2019

Why choosing the right rebreather matters

• Cost of ownership: €6 000–€12 000 upfront, plus sensors, sorb, servicing, and annual training refreshers
• Risk of malfunction: PO₂ spikes, flooded scrubbers, or electronics failures don’t forgive sloppy choices
• Long-term commitment: You’ll train, maintain, and travel with this unit for 5–10 years—make sure it fits you

The initial purchase includes everything you need to dive, but consumables—especially sensors and sorb—shift to predictable, recurring costs. Build them into your yearly budget so your life-support system stays reliable and certification-compliant. Both CCR Liberty backmount and Liberty Sidemount arrive with a full set of four oxygen sensors already installed.

Key CCR rebreather properties to evaluate

1 Oxygen sensor type & reliability

Three independent galvanic sensors are the industry minimum. Look for:

• Automatic voting logic that ignores a rogue sensor
• User-selectable calibration set-points (0.7 bar & 1.3 bar)
• Replace-by date stamped < 12 months out Liberty spotlight: CCR Liberty doubles down on redundancy with two totally independent control units, each carrying its own battery, depth sensor, and dedicated O₂/He sensor set—so one side can fail while the other keeps regulating the loop oceanquest.se.

2 Scrubber duration & performance

Ask for the CE EN 14143 scrubber test sheet. Compare:

• Certified duration at 4 °C / 40 m (cold-water worst case)
• Sorb material (Sofnolime 797 vs. generic)
• Axial vs. radial canister design—radial gives more even gas flow Rule of thumb: ≥ 4 h cold-water duration for serious expedition work.

3 Electronics, HUD & alarms

Your brain isn’t enough in narcosis. Insist on:

• Independent primary & secondary computers
• Full-colour HUD with peripheral-vision LEDs plus tactile or audible alerts
• Field-swappable battery packs rated to > 70 dives per charge

4 Work of breathing (WOB) & comfort

Lower WOB = less CO₂ retention = lower fatigue. Look for:

• CE test result ≤ 3.0 J/L @ 40 m & 40 RMV (Liberty has 2.16 J/L only!!!)
• Counter-lung placement that matches your trim (back-mounted for cavers, chest for photogs)
• Wide-bore hoses to cut flow resistance

5 Redundancy & bailout systems

• Bailout valve (BOV) integrated—one bite switches to open circuit
• Off-board gas ports for deco or cave cylinders
• Spare controller orterials Marine-grade stainless steel, titanium, anodised aluminium, or Delrin, shrug off salt and drops. Carbon fibre for specific applications.

Need a deeper dive? See our step-by-step method in How to choose the right CCR rebreather for you.

Common mistakes when buying a rebreather

Case file: An experienced diver picked a bargain unit lacking local instructors. Six months later his firmware bricked; shipping to the factory cost €500 and delayed a Red Sea trip.
1. Focusing only on price—cheap today can be lethal tomorrow.
2. Ignoring training availability—no instructor, no progression.
3. Under-estimating maintenance—annual overhauls average €400–€600.

If you avoid just one of these pitfalls, this guide paid for itself—underwater and topside.

Final bubbles

Choosing a CCR is less about brand hype and more about matching hard specs to your diving reality. Evaluate each property methodically, talk to divers who log serious bottom time, and refer back to the checklist before you part with a single euro. CCR Liberty and Liberty Sidemount set a high benchmark—use it to judge every other unit in the showroom. Safe, silent diving starts now—see you on the loop!

Author: Jakub Šimánek