The Prism 2 is a fully closed circuit Rebreather, ideal for exploring open ocean, cave, or wrecks. This unit can be electronically or manually controlled which means you choose how you want the loop PPo2 maintained.
Includes shoulder mounted counter lungs and rear mounted radial scrubber which provide 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 at 0.94 J/L.
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.
Hollis Rebreather Course Application
Breathing Loop
The Hollis Prism 2 Tek breathing loop is a keyed one way assembly whic consists of a closable mouthpiece assembly with mushroom/check valves either side to ensure uni-directional flow.
Independent 3rd party testing has also rated the Prism 2 the lowest work of breathing of any mixed gas rebreather available today at 0.94J/L. Click here for actual test reports:ANSTI_Prism2WOB_review.pdf
Status check
With the electronics switched on, the secondary also provides a status check for the battery and displays the set point selected for the dive along with other critical information. The electronics vote between the three proprietary galvanic sensors and control the operation of a low wattage solenoid valve on the oxygen supply.
Scrubber design
A radial flow scrubber canister is mounted vertically on a backplate attached to the integrated BC, between twin supply cylinders (one each, oxygen and diluent).
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 counterlungs. 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.
Counter lungs
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 counterlungs 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.
Secondary Display (COMPUTER)
The Shearwater Predator 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 Predator 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.
Primary Display (HUD)
The Primary Display (HUD) consists of 3 bicolor (red/green) LEDs
mounted on either the right or left 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.
The Prism 2 rebreather has completed 3rd party testing to the EU standard 14143 and met all acceptance criteria.