TRAVEL / SPECIES / CONSERVATION / SUBCULTURE / DISCOVERY / TRAINING / GEAR The advantages of diving Demonstrate Discipline bail-out tank and regulator, and an on a rebreather are many: 3 longer bottom times, To dive these units safely, careful exposure suit adequate for the open- fewer bubbles to scare prep and post-dive care is required for water environment. Added costs include Going with your favorite marine life, and warm, moist each and every dive. “Although recre- the nitrox fills, scrubber material, and the Flow breathing gas. What are you waiting for? ational rebreather diving has come of age, the rental or purchase of the rebreather. Diving bubble-free with there are still crucial things to remem- the Hollis Explorer eSCR ber,” says Weber. “The most important Experience the Rewards 5 on the German WWI is being disciplined. It’s not the same as Rebreathers offer extended dive cruiser Karlsruhe just throwing together a tank, BC and duration, longer no-decompression reg and hopping in the water.” Before times, reduced weight, a warmer gas and after each dive, you’ll get your tank exchange and the ability to get closer to filled with an analyzed nitrox mixture, marine life. “I can get up close and per- insert the pre-pack scrubber canister, sonal with most things that live in the assemble the unit, perform all predive sea with my rebreather, where on open checks — such as positive pressure, nega- circuit I just scare everything away,” says tive pressure, flow rate, bypass regulator Weber. “I’ve been able to get very close operation, relief valve pressure and leak to goliath groupers and ocean sunfish checks — and clean and disinfect the unit on my rebreather, something just not Scapa Flow in the Orkney Islands after the dive. really possible on open circuit.” Diving — off the windswept northern tip of sans bubbles inside a wreck lessens Scotland — is a wreck-diving mecca Figure Out Your Budget the amount of debris that is knocked thanks to the remains of German 4 Courses usually cost between $700 down from the ceiling. “If you’re the World War I battleships and cruisers and $1,500. The personal dive gear you type who can be disciplined enough, a lying on the seabed. need includes a mask, fins and snorkel, rebreather can open doors to encounters This year, I dived the wrecks using reel or finger spool, SMB or lift bag, that you can only dream of,” Weber says. a Hollis Explorer eSCR rebreather. The final dive of the week really showed the true beauty of the unit. The SMS Karlsruhe is one of three cruisers in Scapa Flow, and there is plenty to see along its 367-foot length, most notably an intact stern, com- What’s Your Type? plete with anchor, 5.9-inch deck guns Understanding how a rebreather works can help you and a dramatic bow. With the deep- READY FOR A REBREATHER? choose which one to buy What you need to know before signing up for recreational rebreather training est sections in 82 feet of water, and BY TANYA G. BURNETT There are three primary categories of rebreathers: Oxygen, Semi-Closed Circuit (SCR) and its highest points reaching 45 feet, Fully Closed Circuit Rebreathers (CCR). These systems vary in the manner in which gas even single-tank divers have plenty is added or replenished, but all rebreathers must scrub out the carbon dioxide from the of bottom time, but on the Explorer, I If you associate rebreathers only with is the same thing — you’ve got an Make a Commitment to Learn 2 breathing gas. completed 46 minutes on the seafloor technical diving, it’s time to take a unrestricted pass to get up close and per- You must be ready to understand before I got near my no-deco limits, look at the new Type R, or recreational, sonal with all kinds of ocean life. With no how a rebreather system works, the Hollis Explorer Sport and as soon as I ascended to around The compact and lightweight Hollis rebreathers, such as the Hollis Explorer bubbles or sounds to disturb them, you physics and physiology associated with Explorer Sport’s unique design uses a 55 or 60 feet, my handset displayed Sport (shown in the photo at right). These are accepted as one of them.” this diving, and how to put the unit single cylinder of nitrox, ranging from that I had another 48 minutes before units are lightweight, easy to transport together, test and clean it. The course 32 to 40 percent, and the electronics I needed to surface. That was a total and have sophisticated yet simple elec- Do a Training and Skills Check spans roughly four days and includes feature a predive diagnostic that runs possible no-deco dive time of over 90 1 tronics, plus they let you experience PADI requires that students have nine dives. Specific training is required with just a few prompts to the diver. It’s minutes — and all on a 5-liter tank of electronically controlled to automati- things you never imagined possible. both Open Water Diver and Enriched Air for each model. “Each manufacturer 40 percent nitrox and small scrubber cally analyze the gas mixture, and will of sofnalime. Plus, breathing warm “Imagine having an all-access back- Diver certifications, a minimum of 25 builds its units differently,” says Weber, adjust accordingly to achieve an op- stage pass to all the hot Hollywood parties logged dives and be at least 18 years old. “so each unit is different in terms of timal balance of PPO2 and dive time. gas through the loop helped stave where all the stars know you and love Weber says having a good understanding assembly, prep, emergency procedures, The unit uses a refillable absorbent off the cold of the 46-degree water, you,” says James Weber, a Semi-Closed of the basic principles of gas-exchange post-trip prep and maintenance.” You cartridge, has optional CO2 tracking and with massively reduced bubbles, and offers a maximum dive time of Circuit Rebreather and Fully Closed physics, such as PPO2 (partial pressure can rent a unit for the course, and Weber I could get close to any marine life I two hours. MSRP: $4,995.95; encountered. — Sport Diver EMEA Circuit Rebreather instructor with of oxygen) and FO2 (fraction of oxygen), says that “once you learn how to dive one optional CO2 monitor kit available Editor Mark Evans PADI Five Star Force-E Scuba, Riviera and excellent buoyancy skills will make rebreather, you can get an additional unit for $495.95 Beach, Florida. “Diving a rebreather the learning process a bit easier. qualification on another unit.” G. BURNETT TANYA HOLLIS. OPPOSITE: COURTESY BROWN; JASON FROM TOP: 20 SEPTEMBER 2015 | SPORTDIVER.COM SEPTEMBER 2015 | SPORTDIVER.COM 21 .