Prism 2

The Prism 2 is a fully closed circuit Rebreather, ideal for exploring open ocean, caves, or wrecks. This unit can be electronically or manually controlled which means you choose how you want the loop PPO2 maintained.

Includes option of front-mounted counterlungs or back-mounted counterlung. Combined with the rear mounted radial scrubber, the Prism 2 provides easy breathing with low resistive effort and low hydrostatic loading. The Prism 2 has also been tested by ANSTI at 100M and has the lowest WOB of any mixed gas CCR on the market. The standard kit includes an electronic secondary control and primary LED displays with a backplate/wing assembly that provides a complete kit ready to dive out of the box. Tanks and valves are purchased separately.

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Detailed Specs

FRONT MOUNTED COUNTERLUNGS

Dual, front mounted counterlungs provide the diver with a flexible reservoir equivalent to the maximum displacement of the diver’s own lung volume and ensures the lowest possible hydrostatic loading.

These counter lungs are fitted with both automatic and manual gas addition systems and a variable volume control valve (used upon ascent to vent excess expanding gas volume or to purge the loop). Diluent addition is automatically achieved as hydrostatic pressure increases and the counter lung collapses against the valve actuator.

BACK MOUNTED COUNTERLUNGS

Backmounted Counterlung positions lungs behind the diver leaving the chest free for attachment of additional tanks and accessories. This also allows improved streamlining with less drag and better horizontal trim.

Features a 2 piece bag design for improved WOB performance and easy removal of the internal lung for cleaning or replacement. ADV Upstream Valve design is reliable and resistant to free flow which is a benefit for the addition of valuable diluent gas. All gas delivery systems on the Prism 2 have both automatic and manual function. Water Trapping T-pieces keep excess water from the breathing loop inside the counterlung for easy draining. Streamlined Hose Fittings keep LP hoses routed inside closest to the diver which avoids overhead interference. Machined DIL and O2 MAV controls ensure a rugged and reliable design, also allowing offboard gas plugin on both sides.

Rear mounted radial scrubber

The Prism 2 utilizes a user packed, radial 6lb CO2 scrubber, which features the best possible duration, insulation and work of breathing on the rebreather. The scrubber canister is mounted vertically on the backplate and between twin supply cylinders (one each, oxygen and diluent). The clear scrubber bucket is molded from Engineered Thermoplastic. This Hollis exclusive design ensures the CO2 scrubber is installed, packed and provides a visual for positive loop integrity.

HIGH PERFORMANCE DSV and BOV

Every Prism 2 ships complete with a DSV (Dive Surface Valve) standard and BOV (Bailout Valve) as an available option. The BOV features a high performance regulator valve, is incredibly lightweight and is a direct bolt on for your Prism 2 to replace the DSV. The Prism 2 BOV is considered a basic safety device for the rebreather by many professionals and meets the requirements for training in Technical rebreather courses.

Electronics

The electronics, sensors and batteries are mounted in the electronics head assembly at the top of the scrubber, with supply hoses feeding over the diver’s shoulders into the top of the counter lungs. An analog LED primary display offers a quick reference of unit performance with status and alarm indicators while an independent digital OLED secondary display verifies the unit’s performance.

Heads Up Display

The Primary Display (HUD) consists of 3 bicolor (red/green) LEDs mounted on either the right orleft side of the DSV/BOV mouthpiece just below eye level. Each LED provides a status indicator for its corresponding O2 sensor by using a “Smithers Code” flashing the status on a cycling 5-second loop during the dive.

Secondary Display (Computer)

The Shearwater Petrel is the computer display on the Prism 2 and was chosen for this application as it is one of the most advanced mixed gas CCR computers available today. The Petrel is designed to control the Prism 2 setpoint and uses a basic decompression algorithm known as Buhlmann ZHL-16C which has been modified by the use of Gradient Factors.

Accepts 2L and 3L cylinders with the supplied tank band for flexible gas management
Eye level LED Primary display provides easy to monitor system status
Displays PPO2 for each oxygen sensor is used to control PPO2 manually & assure electronics system is nominal
External power switch is easy to power on
Easy calibration with a push button O2 calibration
Large OLED Secondary Display is easy to read, even for your buddy
PPO2 Monitoring of Three Sensors Continuous display of each sensor’s PPO2, mv reading easy to access
Closed Circuit & Open Circuit, 5 gases supports diluent switching & Multi-gas mix dive plans
2 button push OC bailout – If you have to leave the loop, quickly switches to bailout support
CNS Tracking based on real time oxygen exposure
Software Update via web
Dive Log Download
Stainless Steel Stand Included

All Features

Choice of Front Mounted or Back Mounted Counterlungs.
Industry Best WOB – 1.57 J/L at 40 meters using AIR as diluent
Unit weight when fully charged, in standard configuration – approx. 47lbs
Split counterlungs allows inhale and exhale counterlungs for high work loads.
Counterlung drains make it easy to remove water during a dive
All gas lines external to the breathing loop prevents leaks from affecting the PPO2
Automatic diluent addition valve adds diluent during descent or when the loop volume is low
Manual diluent addition valve adds on board or off board diluent for loop flushing
Gases – Air, Trimix, and Heliox
Manual oxygen addition valve allows for manually controlling oxygen PPO2
Integral harness and BC or Backplate standard makes the Prism 2 ready to dive out of the box
High performance open circuit Bail Out Valve option
Full range of wings/harness gives the ultimate customization

Technical Specifications

Length	21 in (53.3 cm)
Width	17 in (43.2 cm)
Depth	9 in (22.9 cm)
Buoyancy	Neutral
Weight	Approx. 47 lbs with tanks
Scrubber Flow Design	Radial
Counterlungs	Front Mount 3.5L / Back Mount 4.0L
PO2 set points	Adjustable (0.7, 1.0, 1.2, 1.3, 1.4)
O2 sensors	3 galvanic
Sensor life	12 months in air or 100 hours dive time
Heads Up Display	Yes, 9V battery powered sequential LED
Handset	Yes, (Shearwater Petrel 3) powered by Lithium cell
Battery type	9 volt Alkaline / 3.6V Lithium cell
Battery life	40 hrs
Automatic setpoint switch	Yes
Integrated weight system	Yes (Optional)
Scrubber duration EN 14143 conforming testing:	190 min (0.5%, SEV CO2) using 8-12 @ 40 °F/4 °C, 3.0 L/min CO2, 18 fsw/6 msw 190 min (0.5%, SEV CO2) using 8-12 @ 40 °F/4 °C, 1.6 L/min CO2, 131 fsw/40 msw 215 min (0.5%, SEV CO2) using 8-12 @ 40 °F/4 °C, 1.6 L/min CO2, 330 fsw/100 msw