AP Diving RB111 Operator's manual

Issue 6
Open Circuit Bailout Mouthpiece
User Instruction Manual

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Contents
Copyright Notice................................................................................................3
Applicable Law: .................................................................................................3
Manufacturer:.....................................................................................................3
EC Type Approval: ............................................................................................3
EC PPE Article 11B Approval:...........................................................................3
General Precautions and Warnings...................................................................4
Introduction........................................................................................................5
Two Modes........................................................................................................6
The Dual Valve..................................................................................................7
Initial Configuration............................................................................................8
Preparation and Setup.......................................................................................9
PRE-DIVE INSPECTION check list.................................................................11
Diving With Nitrox............................................................................................14
Cold Water Diving............................................................................................15
Post Dive .........................................................................................................16
Maintenance Schedule....................................................................................17
Service and Repair..........................................................................................18
RB110 Main Assembly .................................................................................... 19
RB111 Dual Valve Assembly...........................................................................20
RB112 Front Cover Assembly.........................................................................21
Warranty Information.......................................................................................22

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Copyright Notice
This instruction manual is copyrighted, all rights reserved. It may not, in whole or
part be copied, photocopied, reproduced, translated to any electronic medium or
machine readable form without prior consent from Ambient Pressure Diving Ltd.
©2008 - 2017 Ambient Pressure Diving Ltd.
OCB Instruction Manual
Please read the instructions in this manual carefully before using the Open Circuit
Bailout (OCB) mouthpiece.
Applicable Law:
All products are sold on the strict understanding that only English Law applies in
cases of warranty claims and product liability, regardless of where the equipment
is purchased or used. Should a claim be made then the venue for this would be in
Truro, England.
If this clause in not acceptable to you or your family then return the product
unused to your place of purchase for a refund.
Manufacturer:
Manufactured in the UK by Ambient Pressure Diving Ltd, Unit 2C, Water-Ma-Trout
Industrial Estate, Helston, Cornwall, TR13 0LW, Telephone [phone].
EU Type-Examination:
EU Type-Examination approved by SGS United Kingdom Ltd, Unit 202b Worle
Parkway, Western-Super-Mare, Somerset, BA22 6WA, Notified Body Number
0120.
EU Conformity Assessment:
on-going certification to allow CE marking under Article 11B of the PPE Directive
89/686/EEC is granted by Lloyds Register Quality Assurance Ltd. CE0088.

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General Precautions and Warnings
Before using this OCB mouthpiece, you must receive instruction and certification
in diving rebreathers from a recognised training agency. Use of this OCB by
uncertified or untrained persons is dangerous and can result in injury or death. It is
very easy to configure the OCB and/or use it in an unsafe manner. Even if specific
training is undertaken in its configuration and use, it is still possible to injure
yourself through carelessness.
The Inspiration XPD, EVP and EVO closed circuit rebreathers’ CE certification to
EN14143:2013 is unaffected by the addition of this OCB mouthpiece.
OCB maximum certified depths: Closed Circuit = 100m. Open Circuit = 50m.
This OCB mouthpiece meets the requirements of the Personal Protective
Equipment Directive 89/686/EEC –CE certification when fitted to a first stage
regulator conforming to EN250:2014 or EN13949:2003 and to an Ambient
Pressure Diving Ltd rebreather.
This OCB mouthpiece is not configured for buddy-breathing (multiple users).
Factory / Dealer prescribed service for this OCB mouthpiece is recommended at
least once annually by a factory trained Ambient Pressure Diving service
technician. Disassembly or repair must not be attempted by persons who are not
factory trained and authorised by Ambient Pressure Diving.
Warning! Training alone is not sufficient to ensure your safety. Correct
maintenance and diligent use of the equipment is essential. If sufficient
forethought has not been given to equipment configuration, risk analysis, dive and
emergency planning you could with one simple operation –changing from CC
mode to OC mode –feed yourself gas which will not support life. DO NOT
underestimate your capacity to make a mistake. Everyone makes mistakes, but
making a mistake with the OCB can prove fatal.
Warning! If additional components are used in the medium pressure gas supply,
for instance a gas connection system or gas switching block, it is important to
realise that these may interfere with the gas flow to the OCB and degrade the
breathing performance preventing the OCB from supplying sufficient gas to a hard
working diver at depth. Additionally, if they interrupt the gas supply the OCB may
be critically damaged on descents.
Warning! DIVING WITH HYPOXIC GASES
Know your maximum and minimum operating depths of the gas connected
Using Hypoxic Gases ON or NEAR the surface has and will KILL!!
Check and double check –don’t underestimate your capacity to make a mistake!

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Introduction
Thank you for choosing an Ambient Pressure Diving product. This OCB
mouthpiece has been designed and manufactured with pride under a Lloyds
Quality Assured BS EN ISO 9001 quality management system.
This OCB mouthpiece is covered by Ambient Pressure Diving’s 2 year warranty
against defects in materials or workmanship. This warranty is only extended to the
original purchaser, and is not transferable. For more information, be sure to read
the warranty section of this manual, and remember to save your sales receipt. A
copy of the receipt must be presented whenever obtaining warranty service.
The function and performance of the OCB relies greatly on the care and
maintenance it receives, in addition to regularly scheduled factory / dealer service.
Before you dive with your new OCB mouthpiece, it is important to read this manual
in its entirety to become familiar with its features, as well as the correct procedures
for setup, pre-dive inspection and post-dive maintenance.
Please read on to learn how you can obtain the maximum functionality from your
OCB mouthpiece, and maintain its like-new performance for many years to come.

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Two Modes
The OCB Mouthpiece has 2 Modes:
1. CC. Closed Circuit rebreather diving position.
2. OC. Open Circuit diving position. This is the BAIL-OUT mode.
The two modes are selected by rotating the lever forwards or backwards, which in
turn rotates the internal components within the main body. The Rebreather mode
is activated by rotating the lever to the backward position where the lever is in line
with the mouthpiece. The Open circuit mode is activated when the lever is rotated
forward to the ‘up’ position.
The lever is best operated by the diver resting his right hand on top of the
corrugated hose and placing an extended thumb between the two lugs of the
lever.
REBREATHER
OPEN CIRCUIT

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The Dual Valve
The OCB Mouthpiece utilises ‘AP’s new patented Dual Valve Technology. This
new demand valve enables the diver to quickly and easily change the medium
pressure (7 to 14 bar) supply hose routing from left hand to right hand, without the
need for major disassembly, adjustment or any special tools.
The Dual Valve can be switched between left hand and right hand in simple steps:
1. Turn the gas off and purge.
2. Unscrew (anti-clockwise) the supply hose and then the 9/16” UNF blanking cap
from the opposite end until the threads disengage and pull, withdrawing the
plunger. (If a tool needs to be used to undo these fittings, protect the plastic
moulding by preventing the Dual Valve Body from rotating by using a 17mm
spanner/wrench on the adjacent hexagon nut).
3. Fully screw the plunger into the blanking cap until the threads disengage and
then gently slide the plunger into the opposite side of the dual valve.
4. Screw the blanking cap on until it is tight against the shoulder, covering the
thread. You should be able to do this up without tools. If resistance is met, you
need to ensure the plunger is fully into the blanking cap and the threads are clean
and sufficiently lubricated with silicone or oxygen compatible grease, whichever is
appropriate for the gas you intend to use. While finger-tight is sufficient it is
prudent to just nip it up lightly using two 17mm spanners.
5. Reconnect the supply hose. Turn the gas on slowly and test for leaks and
breathing performance prior to diving.
CAUTION: When switching the valve from left to right hand hose routing, use two
17mm spanners/wrenches, one on the hexagon of the blanking cap or hose and
the other on the adjacent hexagon immediately next to the valve body. Using just
one spanner/wrench on the blanking cap or hose may damage the valve body.
RIGHT
LEFT

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Initial Configuration
The OCB mouthpiece has been supplied with both Inhale (RB07/03) and Exhale
(RB/07/04) convoluted hoses. The hose length is set at the factory. These hoses
are shorter than the standard front rebreather hoses as the OCB is wider than the
standard mouthpiece. However, if the hose length is too long as shown above, the
hoses will need to be cut to the correct length. To reduce the length of the
convoluted hoses, follow the steps below:
1. Remove the convoluted hose from the T piece.
a. Using the special tool (RBTOOL12), undo the locking rings and remove the
split rings.
b. Pull the hose from the connector.
2. Cut the hose square, to the correct length using scissors.
3. Re-assemble in reverse order, ensuring the lips on the inside of the split rings
hook over the flange on the connector fitting.
4. Test for leaks prior to diving.
The OCB mouthpiece has been supplied with a 1.5m Medium Pressure (7 to 14
bar) Hose, so it can be used to supply gas from a side-mounted cylinder. For
supply from an onboard cylinder the hose may have to be shortened depending on
the hose routing and whether you connect direct to the first stage or to the
manifold.
Learn how to shorten AP Diving hoses with re-useable end fittings by following the
links below:
http://www.apdiving.com/en/rebreathers/resources/manuals/
http://www.apdiving.com/en/rebreathers/resources/videos/

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Preparation and Setup
Careful consideration needs to be given to your intended use and purpose
for this product as this will greatly affect the setup and configuration.
a. Gas volumes available, particularly at depth, need to be considered and
be adequate for the intended use.
b. Similarly, gas types must be considered and be adequate for the intended
dive. e.g. Hypoxic gases fed through a 2nd stage are very dangerous in the
shallows allowing normal breathing right up until you lose consciousness.
It is very easy to make a mistake in the setup, particularly when changing
from a deep dive to a shallow dive and vice versa as the setup may be
different for each dive and you can easily introduce extra dangers if you
keep the same configuration.
Training and planning are essential and it is not within the scope of this user
manual to offer advice as to the best configuration for all dives but it is
essential to ensure you have a respirable gas mixture available at all depths
AND ensure you breathe the appropriate gas at the appropriate depth.
Failure to do so may result in loss of life.
Risk analysis is an essential part of dive planning. By using this type of
valve you have a single point failure for both open circuit gas and closed
circuit. It is recommended to include this fact in your risk analysis and
consider having an additional 2nd stage regulator on each cylinder intended
for open circuit breathing.
Whether you choose to feed the gas from an offboard cylinder or onboard –
the supply hose must be fitted to a suitable 3/8” UNF threaded outlet,
designated Low Pressure (LP) or Medium Pressure (MP). The supply
pressure must fall within the range 7 to 14 bar, nominally 9.5 bar. The valve
is balanced and should need no adjustment for the different pressures.
Warning! When in CC mode, the open circuit part of the valve is sealed,
unlike a normal 2nd stage which is always at ambient pressure. Therefore it
is essential to ensure the gas is switched on for the entire dive. If you leave
it switched off you will catastrophically damage the diaphragm. Switching
the gas on then off should also be avoided as catastrophic damage will still
occur to the diaphragm, it will just occur deeper than if you hadn’t turned the
gas on.

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Preparation and Setup Cont…
It is recommended that you DO NOT fit an isolation valve, such as a flow-
stop slide valve, between the 1st stage and the OCB for three reasons:
1. If you do fit one and dive with it closed, the diaphragm will be
catastrophically damaged as you descend.
2. When it is closed the OCB’s pressure relief valve (which normally
operates at around 18 bar) cannot operate in the event of a first stage
“HP seat leak”.
3. If it is closed, you have turned a “one action to go to open circuit” into a
two action procedure.
However, if you fit an isolation valve, such as a Flow-stop slider, ensure:
a You dive with it OPEN.
b You fit an additional pressure relief valve, such as the APD RB17, to
the first stage.
c. You practice it’s operation often so you know for sure which way is
open.
Ensure the blanking cap has been securely screwed into the opposite side
of the dual valve from the medium pressure hose. If this is not correctly
located the OC demand valve will “free-flow”.
Warning! Check the medium pressure supply hose is connected onto the
OCB before opening the cylinder valve. If this is disconnected the flailing
hose end can cause serious damage to eyes or objects nearby.
Check for leaks by immersing in water.
Make sure the OCB mouthpiece is in the OPEN circuit position then depress
the purge button momentarily to blow out any dust, debris or water which
may have entered. Release the purge button and listen to ensure that the
OCB mouthpiece does not continue to flow air after the purge button is
released. If it free-flows due to the venturi, simply placing a finger over the
mouthpiece opening should be sufficient to disrupt the venturi effect and
allow the valve to close, the same as any normal high performance 2nd
stage.