Inspiration xpd, Inspiration evp or Inspiration evo?

    Choosing your rebreather is the most important diving equipment decision you may ever have to make. There are some important questions you should ask before you invest.

    The AP Inspiration range can be configured from recreational to technical CCR spec - so whichever model you choose, it will develop with you as you progress.

     Photo by Greg Regnier




Cylinder Size 2 x 3 litres 2 x 2 litres 2 x 2 litres
Scrubber Duration 3 Hours* 3 Hours* 2 Hours*
Ready-to-dive Unit Weight 29.5kg 27.5kg 24.5kg
Unit Height 57.5cm 51cm 47.5cm
Width x Depth 40 x 35cm 40 x 35cm 40 x 35cm
Summary Extended scrubber & cylinder duration. Perfect for deeper longer diving More compact than the Inspiration XPD. Extended scrubber Compact, light and easy to fly
Mission Deep tech, caving, film-making, repeat diving, deep support, expedition diving All dive profiles. Good for travel Perfect travel unit. Reef to depth. Ideal for smaller body frame
Quick Description The ultimate dive machine The perfect all-rounder Travel light, dive deep

Wing & Counterlung Colours Grey/Black or Yellow/Black Grey/Black or Yellow/Black Grey/Black or Yellow/Black
Case Colour Options Yellow or Black Yellow or Black Yellow or Black
Integrated Weight Harness Size S M L XL XXL S M L XL XXL S M L XL XXL
Wing Size 16KG or 22.5KG 16KG 16KG
Counterlung Option Over the Shoulder or Back Mounted Over the Shoulder or Back Mounted Over the Shoulder or Back Mounted
Over the Shoulder Counterlung Size M L XL M L XL M L XL
Back Mounted Counterlung Size Small or Standard Small or Standard Small or Standard
Trim Weight Pockets
Automatic Diluent Valve (ADV) Optional Optional Optional
Auto Air for Open Circuit Bailout
Open Circuit Bailout Valve (OCB) Optional Optional Optional
Recreational 1 and 2 Software
Nitrox Deco Software Optional Optional Optional
CO2 Scrubber Monitor (Tempstik) Optional Optional Optional
CO2 Sensor Optional Optional Optional
Communicator Software & PC Interface
Logviewer Software
Software Upgradeable
Head-up Displays
Audible Warnings
Dual Power Supplies
Battery Status Indicator
Sealed Battery Box
Automatic Setpoint Switch
Language Options


Some points to consider when making your choice...

The difference between the 3 models?

This can be summed up quite simply: Inspiration… Small, Medium and Large. They are identical apart from chassis length and they have different sizes (durations) of scrubber unit and cylinders. All 3 models have the same spec in terms of build quality, control systems and upgrade options. (exception: only the larger unit - the Inspiration xpd - can upgrade to a 22kg wing because of it's chassis size)

So which Inspiration model is right for me?

The answer to this will be a balance between the type of diving you plan to do and how much importance you give to the size and weight of the unit chosen in relation to your body frame size.

Points to consider:

  • All 3 units can be dived to technical depths with appropriate planning for diluent gas mix and off-board bailout gas contingencies.
  • When flying abroad you can reduce hold luggage weight by about 10kg on all units by packing the scrubber and head in your hand luggage and using the dive resort’s cylinders.
  • Each model has a full range of harness sizes from small to XXL.
  • There is a only a 5kg difference in ready-to-dive weight between the xpd and the evo.
  • All 3 units are approved (and can be spec’d for all training levels Rec to Tec) by TDI, IANTD, ANDI, IART, ETDS, PTA, SSI, ITDA, BSAC, PSA and RAID and PADI.

So, we seem to be saying any model is right for you. To an extent this is true.

Some conclusions

  • If diving the unit without additional bailout contingency, the Inspiration xpd with 3 litre cylinders and 3 hour scrubber may be the unit of choice if you intend to do multiple repeat dives without refilling consumables between dives.
  • Typical consumption per dive is about 30 bar from each cylinder so you would generally have sufficient bailout redundancy for subsequent dives with all units. However, psychologically, you may feel more comfortable with the unit with the larger cylinders.
  • The smaller units may be a better choice if you intend to frequently fly abroad to dive. Although, with AP’s extensive global support network, the heavy items – cylinders and sofnolime - can be sourced locally.
  • The smaller units may be the best choice if they are a better fit to your body shape and size (especially your back length) and you place greater importance on fit and pre-dive comfort than other considerations.

 As an underwater cameraman… the basic reasons that I switched from heavy dual tanks to a nice light rebreather unit like [the Inspiration evo] are… simplicity, quietness… I can stay down longer… It gives me 100% humidified gas… It is just wonderful for gas consumption… there’s no up and down movement when I breathe… and small animals in the ocean totally ignore me… like I’m one of the rocks!

Jim Kozmik (Assoc. Producer Sport Diver TV, The Blue Realm, Discovery World & Animal Planet)
Jim Kozmik


How is the Inspiration different to other CCRs?

  • Unique, patented, intelligent Dual Control of PO2
  • Multiple redundancy and unit monitoring features
  • Unique backup intelligent dual power supplies
  • Unique 3 oxygen-cell voting logic system
  • Benchmark oxygen control accuracy +/- 0.05 bar of setpoint
  • Patented scrubber monitor
  • Unique fibre-optic Heads Up Display (robust, reliable and unlike other makes, not prone to failure due to flooding)
  • Production unit built by an established 45+ year manufacturer with all that implies about quality and on-going availability of support and spares
  • Market leaders with global network of instruction, advice and supply



How much does it cost?

[Prices below are 2016 recommended retail prices]

How much does an Inspiration cost?

From £5,219 for a ready-to-dive unit. The same price for each of the 3 models.

Popular optional upgrades include:

  • ADV (Auto-add Diluent Valve) with Flowstop gas isolator - about £200
  • Open Circuit Bailout Mouthpiece - £612
  • Scrubber Monitor - about £300
  • CO2 Sensor - £649
  • Nitrox or Trimix deco software - about £117 each

What about running costs?


Inspiration xpd and evp = about £8.50 per 3 hour fill
Inspiration evo = about £7.00 per 2 hour fill


At current UK prices:

Inspiration xpd = about £1 per 3 litre x 200bar Air fill and £6 per 3 litre x 200 bar Oxygen fill

Total = £7 (for up to 10 hours diving)

Inspiration evp and evo = about £1 per 2 litre x 200bar Air fill
and £4 per 2 litre x 200 bar Oxygen fill

Total = £5 (for up to 6.5 hours diving)

Other gas costs apply if using nitrox or trimix instead of Air diluent and if using additional bailout cylinders.

Oxygen Cells

3 x £58 each = about £174 per year (varies with dive frequency & duration)


N.B. All new units from October 2014 have a rechargeable battery pack supplied as standard together with a rapid charger unit and a full set of worldwide power adaptors for both mains and 12V DC supplies

For pre-Oct 2014 units with disposable batteries: cost = between £10 and £15 to change both batteries - the main and backup power supplies.
(battery-life varies with how often you use the backlight and it's intensity setting - but on average each battery lasts about 15 hours, therefore total power time = about 30 hours)


Chemgene disinfectant = about £25 for 100 litres (dilute) (use varies = approx 40 dives)


What about training?

Unit-specific rebreather training is compulsory before you buy your Inspiration. However, you are allowed to train on your own unit if you arrange this with your Instructor beforehand. All major diver training agencies offer unit specific courses for the range of AP Diving Inspiration Rebreathers. The AP Inspiration training course typically lasts around 5 days but can vary depending on the course level undertaken...

1st level recreational rebreather training

This Introductory level lets you dive to a maximum depth of 18 metres using a unit specced to minimise diver intervention. This simplifies the training drills and encourages you to bailout to open circuit should any alarm occur.

2nd level recreational rebreather training

On the 2nd level, you’ll progress to a maximum depth of 40m whilst still maintaining a simple approach to diving the rebreather. The full 40m training course teaches you to deal with a variety of emergency situations so there’ll be a much greater level of diver intervention. The importance of full kit preparation is covered, along with full use of all the unit’s features and post-dive cleaning and maintenance. The pre-requisite for this course is usually advanced nitrox.

Going further, and deeper...

Further training levels are possible after you’ve reached a level of experience that allows you to progress to decompression diving using Normoxic Trimix gases and ultimately Hypoxic Trimix gases. With practice and advanced instruction you be able to take on deeper and longer exploration dives to 100m. Please contact an instructor on our full Worldwide list of AP Rebreather Instructors who will provide further details on training, availability and costs.



What to ask about any CCR

Not all rebreathers are the same. Ask the right questions, narrow down your options and make an informed decision that suits your needs.

Is your Closed Circuit Rebreather CE approved?

It should be because CE approval means rigorous third-party testing for important performance issues such as work of breathing. Don’t let people tell you CE approval doesn’t matter. It is a crucial, independently ascertained set of standards made with reference to human physiology – common to divers worldwide – not just to Europe.

If the unit uses oxygen controllers (has an automatic option) does it have independent dual controllers?

It really should do - otherwise you have no backup in a system you are relying on to keep you alive. Only AP Inspiration rebreathers offer dual independent oxygen controllers.

Is there a backup power source?

If your unit uses battery power to function, then there should be an independent backup battery pack and a mechanism to switch seamlessly (and automatically) from one to the other should it be required. AP Diving has this sort of redundancy built in to the Inspiration range as standard.

What is your CCR’s depth rating?

If Trimix / Heliox is used instead of air as the diluent supply and modification is made to the bailout contingency, AP CCRs can be dived to depths of 100m+. They are routinely tested in unmanned trials to much greater depths and dives to depths of 110-120m have been achieved many times. Expeditions to 130m+ are now common.

Does the CCR you’re looking at have a choice of Over-the-Shoulder (Front) or Rear Mounted Counterlung?

There really isn’t a great deal of difference between the two, but there are advantages to each. Only AP Diving offers divers the choice with both options carrying CE Certification.

What type of oxygen injection system is used in your CCR?

Different systems on the market include: Constant Flow Orifice, diver adjustable Variable Flow Orifice, a Static Solenoid or a Dynamic Solenoid. If you are looking for a CCR with the option of automatic Setpoint control, look for one with a Dynamic Solenoid for continuous and instant reaction to changes in oxygen partial pressure in the diving loop. All AP Inspiration rebreathers offer a Dynamic Solenoid as standard and as a result set the benchmark in O2 control accuracy.

How well will your CCR maintain constant PO2 during ascent?

This really comes back to controllers. During ascent the partial pressure of oxygen in the diver’s breathing loop can drop dramatically and to hypoxic levels as the ambient pressure drops. Unless the CCR’s oxygen controller has the ability to react correctly and rapidly to these changes, the unit is poorly designed and the diver is at serious risk. AP Inspiration controllers reactively control the variable solenoid valve timing ensuring oxygen pressure is maintained with benchmark accuracy, +/- 0.05 bar of Setpoint. Even during fast ascents, there is no need for manual intervention.

Does it have a CO2 scrubber performance monitor?

The scrubber bed is where carbon dioxide is removed from exhaled breath. The factors affecting scrubber duration – depth, work rate and water temperature – are too varied to offer accurate predictions of scrubber life for all possible conditions. Since the chemical reaction that takes place in the absorbent generates heat, a smart way to monitor performance is to compare temperatures across the bed and display that to the diver. The manufacturer’s stated duration guides (3 hours or 2 hours) are conservative as they are achieved under deliberately harsh test conditions. The AP Inspiration Scrubber Life Monitor takes into account the actual conditions and displays in real-time what is actually going on. It takes the guess-work out, allowing you to extend scrubber duration with complete confidence.

Does it have a CO2 Sensor?

By following a few basic ‘rules’ and sticking to certain guidelines, CO2 breakthrough can be avoided, but many divers feel more comfortable and secure with this type of sensor in place. AP Diving offer an optional CO2 Sensor which is an ‘active warning device’ designed to alert the diver when the CO2 content of the breathing loop is approaching a dangerous level. This could be due to depletion of the CO2 absorbent canister or incorrect assembly resulting in CO2bypass of the canister. 

Does it have a Head Up Display?

Does it have Heads Up Display (HUD) and what information does it show to the diver? A HUD is a useful tool, but some are at best overly complicated, at worst confusing – the last thing you want at depth, or in critical situations. A HUD should only convey exactly the information necessary for you to fly your unit safely, including warnings when PO2 is outside set parameters, when battery power drops, and when your scrubber is reaching the end of its effective life. The AP’s unique fibre-optic (no flood) HUD keeps it simple. Green for Go… Any red, check the handset.

Can your CCR be upgraded for Technical Trimix Diving?

Not all CCR divers are interested in technical diving, but if you one day decide to go down this route, ask yourself… "Will I have to sell my unit and start again with a new rebreather?" If you choose an AP Inspiration Rebreather you won’t have to - because all 3 Inspiration models can be configured and upgraded to suit all levels Rec to Tec.

Does it have a real-time Nitrox / Trimix computer designed and manufactured by the same people who built the CCR?

It should. Some CCRs use controllers and computers from third-party suppliers. This may suit some risk models and manufacturing philosophies, but not ours. The more you mix and match, the more likely you could face compatibility issues, glitches, or worse – not something you want to be worrying about as you fly under a wreck at 80m! AP Diving’s Vision controller and integrated deco computer is the product of over 15 years research and has been tried and tested in labs, in-water and in depth. Our Vision systems are bespoke and purpose built for the kit they run, so you can be sure they’ll deliver the performance and reliability you expect.

Does your CCR offer a PC Interface and Dive log download?

A nice feature to have. Amazing when you can send that log to the manufacturer for diagnostics. AP technicians routinely use the dive log memory for diagnostics when servicing units or offering advice to customers.

Does it have visual and audible alarms for crucial issues such as low or high PO2, high CO2, and scrubber life?

Many CCRs only have visual alarms. At AP Diving, we believe it is vitally important to have both. Think about it. In a critical situation, under stress, your judgement may be impaired, you could be distracted. With both senses alerted you are much more likely to recognize the warning and respond in time.

Are parts and service available worldwide?

If you travel, it would be nice to know that in the event of something breaking, a replacement part is not sitting in a warehouse someplace on the other side of the world and a day or two away from access to shipping. AP Diving make 95% of all products in-house which means spares can usually be shipped the same day. A simple call or email to the factory here in the UK and you tap into our legendary customer service. Most of our staff are divers themselves and we will always endeavor to go the extra mile to keep you diving. Add to this our global distribution network in which AP regional distributors and many dive centres worldwide hold stock of common spares and you can be reassured - we’ve got your back.

How much service is required?

Leading-edge industrial design using solidly made quality parts all put together in an ISO 9001 factory – or shoddy components outsourced to the cheapest off-shore knock-off house? One approach leads to less servicing and longer life. No prizes for guessing which. At AP Diving, we manufacture 95% of all components on-site in our UK factory. We test 100% of our components on-site at our UK Test Centre. And when things do go wrong, we have an after-sales and servicing department run by knowledgeable people who love diving and love helping you dive.

AP Inspiration rebreathers meet and beat all the above criteria, because at AP Diving we’ve been asking questions like these since we began CCR manufacture over 18 years ago.



How does CCR compare to other advanced diving options?

What are the advantages over open circuit technical diving?

AP CCRs maintain a constant PO2 (variable fraction of O2) at all stages of the dive and so deliver the best oxygen-rich mix for every depth. The Inspiration therefore offers all of the increased depth, time and deco advantages of advanced open circuit mixed-gas diving but without the expense, time and hassle of pre-mixing multiple gases for pre-planned target depths, excessive cylinder carrying or gas-switching during the dive.

Compared to open circuit the Inspiration offers silent, warm-breathing, comfortable diving - but arguably the key advantage is the extreme versatility of the system. Because your nitrox gas is mixed onboard, on-the-fly (as your depth changes) the same prepped unit is ready to dive deep or shallow. Consequently, if the planned dive & depth is blown out… you haven't wasted expensively mixed gas… you can find a sheltered spot around the headland and dive a different depth instead.

What are the advantages over semi-closed rebreathers?

Semi-closed rebreathers are essentially, less versatile: in that they still require a planned pre-mixed gas (fixed fraction of O2, variable PO2) and therefore only deliver an ideal mix at the target depth of each individual dive. They are less gas efficient and less “silent”: as the name suggests, they are only closed circuit for some of the time, venting excess gas every few breaths or so. They also offer less time and deco advantages than closed circuit.



Credit – Cyrille Mulard, Te Honu Dive Centre.



The Inspiration range can now be configured for all CCR training organizations including all PADI TecRec Levels

In the summer of 2011, the worldwide dive-training agency, PADI, added Closed Circuit Rebreathers to their TecRec training programme. All 3 AP Diving rebreathers are PADI approved and can be specified by the customer to meet the PADI spec requirements. One AP rebreather does it all from Rec18 to Tec100 - with plug-n-play upgrades as you go for the hardware and simple system key changes for the software.

PADI Type R (recreational) Rebreathers spec

  • Depth limited (by the software) to 18m (Rec1) and 40m (Rec2)
  • Self-activation switch (standard on all AP units)
  • Open Circuit Bailout (OCB) fitted
  • Auto Diluent Valve (ADV) fitted
  • Gradual setpoint change

PADI Type T (technical)

  • As above plus
  • Manual oxygen and diluent inflators added to (blanked) ports
  • Gradual, manual or automatic setpoint change = optional for Tec100 divers


The advantages of the Inspiration for the PADI instructor / resort

For the PADI instructor or resort, the Inspiration range offers great flexibility and economy as you don’t have to buy multiple units. You can upgrade (or downgrade) the one AP rebreather to suit your student’s training level. The same applies to the PADI trainee CCR diver. The unit will grow with you as you progress.