About a year ago I purchased a Shearwater Petrel to use as an Open Circuit Mixed Gas Computer and also as a backup computer to my JJ-CCR.

The Petrel is a great computer; it’s easy to use, not only as a mixed gas computer but for regular Air and Nitrox diving too.

As a Dive shop owner and IANTD Instructor Trainer, I am regularly asked “which computer would you buy?” There are so many computers on the market and I have used virtually all of them, but I am just astounded at how good the Shearwater Petrel is.

Benefits of the Shearwater Petrel and Shearwater Predator:

Gradient Factors (GF) – GF basically allow the user to set the conservitism for the computer and the high gradient factor can even be changed on the fly to get you out of the water faster, if you need to. It even shows how saturated your tissues are and how close they are to the M-Value.

The Algorithm is a ZHL-16C algorithm, which means that there are 16 tissue compartments offering the user a safer approach to Decompression planning, and the Buhlmann algorithm is a well tried and tested algorithm.

Clear Display – the Display on the Shearwater is just incredible; it is easily seen in any conditions. I recently did some wreck penetration in low vis in the UK and it really made a massive difference against other computers I’ve used in the past.

So far I have completed around 200 hours of diving on the Petrel and there isn’t a scratch on the screen. It has a laminated display which can be removed and replaced easily.

User Friendly – So many computers nowadays have buttons that are difficult to press and have strange labelled menus that really mean nothing to the user. The Petrel really makes a huge difference; the left button scrolls through the menu and the right button selects, which makes life really easy, especially while gas switching on the fly. Menus are simply labelled with “next” and “exit” clearly marked allowing user friendly control, even with clumsy 5mm gloves or dry gloves.

PO2 – As a back up to my JJ-CCR (which uses the big brother to the Petrel, the “Shearwater Predator”), it works really well. I can change the PO2 from low set point to high set point or just set it to change automatically at depth. It won’t follow my exact PO2 because it isn’t verifying my gas in the CCR, but it will get close enough should something happen to my onboard computer. I can of course use my HUD to get me out of the water, but having the extra back up makes a massive difference, especially while teaching courses.

Open Circuit or Closed Circuit – Switching between the 2 is effortless and extremely convenient, especially if using a CCR and if you need to bailout.

Bluetooth – The Petrel and Predator both easily connect to a Mac or PC using bluetooth technology so logging dives or examining a dive profile after a training dive couldn’t be easier.

Nitrox and Trimix– The Petrel and Predator allow 5 Open Circuit gasses and 5 Closed Circuit Gasses. For the kind of diving I do, this is a really great idea. They allow me to store my favorite Deco gasses – 32%, 50%, 80% and 99%, and also my favorite back gas like Trimix 18/35.

The build quality is also top notch. I personally use a 3.5V SAFT battery; standard AA batteries don’t last very long, so this really makes a big difference.

Straps are easily adjusted for either a wetsuit or a drysuit, and even with a thick undersuit I still have enough length on the straps.

Price – Dive Gear Express retail the standard Petrel without the Fischer cable socket for just under $1000, and with the socket for $1500. Personally, I think it’s worth every penny.

To have a computer that has so far given me over 200 hours and hasn’t had any issues is just amazing; and I hope to re-review it in a couple of years from now to let you know how it’s still performing!

Top Tip – Buy the case that is offered online, it’s neoprene and makes a big difference to keeping it in great condition.

For more information contact me at www.caribbeantechnicaldiving.com or email me at americantechguru@scubaverse.com