An inline solenoid shut off valve should be installed on every rebreather. It gives control back to the diver for dealing with ascents and troubleshooting. We originally had an inline option but the location was less than optimal. The rear location made it an emergency shutoff rather than a tool.

The new EZ shutoff is a culmination of ideas from some O2ptima divers using various components to reposition the shutoff near the manual addition valve. The idea was sound, but available components added to many parts. Our manifold, which feeds the solenoid, puts everything together in a very streamlined package. It also allows for easy connection of an off board oxygen source. Only one hose leaves the oxygen cylinder and plugs into the manifold mounted to the oxygen addition.

I have been diving it for a couple of months now and find it for more convenient and useful than the original rear mounted inline shutoff valve. It can re retro fitted to any O2ptima.

Pics are forthcoming on our website. For now you can see it in the RBW video here:  Rebreather World O2ptima Video

Lamar

The O2ptima rebreather uses the ExtendAir cartridge for a number of reasons.  Some like to argue that granular is cheaper and easier to get.  I won’t argue with that because if that’s your belief then my arguments won’t matter. However, convenience is key for me and that’s what the ExtendAir rebreather cartridge provides. Duration sometimes comes into question. Let’s look at that.

The cartridge is designed to scrub 240 liters of CO2 and since you metabolize 1 liter of oxygen for every .92 liters of CO2 its basically liter for liter. So it’s easy to look at your oxygen gauge and calculate duration based on oxygen use. We did a rebreather dive two weeks ago at Peacock Springs, swimming from Orange Grove sink to Peacock Springs and back. The swim took 150 minutes and the team average was 30 bar of oxygen to do it.  The quick math for usage is 240 liters (cartridge rating) divided by the bottle size ( in liters).  I was using a steel 27 LP (4 liter), so 240 divided by 4 equals 60 bar. Using this math I only used half of the cartridge duration, so I actually had a 5 hour cartridge duration for that particular dive.

This is very important because canister duration is really about workload and the amount of oxygen you use (or CO2 you produce). Using the cartridge gives me peace of mind for scrubber packing and repeatability for doing the calculations for canister duration. My point is any canister time quoted by someone is based on a set rate of CO2 production and oxygen usage that may not be matched with how you dive. The cartridge testing is done based on 1.35 liters per minute, I know CE is 1.6 liters per minute, but I challenge anybody in reasonably good physical shape to maintain that rate. I know I can’t and people tell me I swim fast.  More advantages later.

** tests based on MicroPore testing at 40m at a 1.35 liter CO2 production.

Lamar

By request we introduced dust caps for the O2ptima rebreather head to seal the cartridge without removing it. Later, we introduced calibration caps so a diver doesn’t need to fill the loop multiple times to calibrate the unit. Now we use the calibration caps for both uses. Take the thread protectors from the harness mounting bolts (5/16”) and slide one over the inflator inlet nipple on the calibration cap to seal the head. I am pulling the Dust Caps off the market because I have received a second report of a damaged head. Both heads were pressurized when the caps were put on for storage, but the diver didn’t shut down the oxygen supply. If the Hammerhead wakes up it will inject O2. Do I need to say more?

Use the calibration caps to seal the head if need be. For those that have a set of dust caps, send them to us in Lake City and we can convert them to calibration caps with the inflator inlet for $25.  Email service@diverite.com

Lamar

The latest O2ptima manual is out with more information about the features of the O2ptima. It’s available in our library or listed under downloads on the O2ptima product page. I have had a couple of instructors review it and found it to be more informative then the earlier one. We have a number of updates and accessories slated to come out this year on the O2ptima like the new stand we just released. I will keep you posted as these things are available.

On a side note the NiTek X can be quickly added to the O2ptima. We need to drill and tap the head to insert the cable. I have been flying my unit with both handsets stored away in pockets attached to the bottom of the CL, using the DIVA in PPO2 mode and 4^th cell plugged into the X. If you want to try this just send me your CL and I can have the pockets sewn in place. I can’t give you the pockets but I can give you the time to sew them in place. 

Lamar

The new HID 1000 adjustable reflector assembly has some improvements over the old H10 reflector. The HID 1000 reflector is recessed into the shroud so there is less backscatter and a better pin-point focus. The new shroud protects the reflector from damage as well. They don’t survive sitting your cylinders on it.

The HID 1000 reflector comes standard with the metal Goodman handle on it with the big pad to rest on the back of your hand.  If you have the H10 light the new reflector from the H1000 will fit and you will feel and notice the difference. I wrote this because I have been asked in the field about upgrading the reflector. You can do an upgrade directly with us at the factor and it will only be $59 if you reference my blog. Otherwise, the retail is $99.

Lamar

Many will say that I am never happy because I am constantly trying to improve our products. Well, here I go again with the O2ptima. The O2ptima FX is easy to assemble, however I wanted a better stand that can withstand the abuse of boat diving. I have seen some hybrid material stands made from aluminum that are nice, however I wanted to stay away from aluminum because it will show corrosion after awhile. Plus, I wanted something light weight.

I went back to the original prototype stand, a rigid support stand. I used ¾ inch thick high impact plastic for both the upright and the stand. This along with a thicker shell does the job. It no longer uses the Remora mounting system. There are slots in the shell for the cam straps. You have to use the 1.5 inch cam straps. We’re making quick release buckles to add to the cam straps so you don’t have to unthread them each time you get your bottles filled. The buckles should be ready in 45-60 days. The stand is $199.00 for an upgrade. If your O2ptima isn’t an FX, you need to get a new cover as well so it will be $300 for the upgrade.

The new stand has outrigger D-rings on it for clipping off bailout bottles. You no longer have to have the Nomad buttplate, which means you can sit down on a boat without the rails underneath you. I take delivery on the first 50 units this week. The first 25 upgrades will get the outriggers for free if you tell us you read about it in my BLOG. That’s $40.00 for free. Call us at the factory to set up the upgrade.

Lamar

Rebreather divers need to be sure to follow a pre-dive check list before every dive. There are a number of steps that rebreather divers must complete before getting in the water. Some say that multiple checklists are needed: one for initial setup of the unit, one pre dive and another list for checking the rebreather between dives. Dive Rite provides the initial set-up checklist and rebreather instructors use their experience to help new rebreather divers develop the pre dive/between dive checklist. We have posted one instructor’s checklist in our online library.

A checklist may depend on the dive environment. Someone diving from a boat might have a checklist different from someone walking into a spring or lake where there is more time at the surface before starting a dive.

Tom Mount and IANTD have years of experience in rebreather instruction and will soon release a pre dive/between dive check list for rebreather divers. IANTD’s lists will work for a multitude of rebreathers and they will work for the O2ptima.

Dive Rite will begin providing the IANTD checklists with all O2ptima rebreather units and we will send one to current O2ptima rebreather owners. Send us an email with the serial number of your O2ptima head and a physical address that we can mail the lists to.

Lamar

Lamar and Doug McKenna from Micropore talk about the invention of the O2ptima, the choice of the Micropore Extend Air cartridge and some of the latest O2ptima features at DEMA 2007.This video was originally shared on blip.tv by Dive Rite with a Public Domain license.

The O2ptima manual needs a few updates. We have been working on a few items to add before making the next revision.

These include:

1. The new Delrin HH are easy to use and have some firmware updates added, including a battery indicator.
2. The premix rod was to be taken out of the unit, but I found that on rapid descents the premix rod is advantageous. I assumed instructors would address this until we got a new revision of the manual out. We use a new connector to help with alignment and it is easy to remove when servicing the head. The grommet should be at the base above the sensor disk so the EAC pushes against it to seal against CO2 bypass. I do not recommend putting it on top as it will surely get lost during assembly.
3. The new quick release elbow for the premix rod has a flow restrictor to maintain a constant flow from solenoid and adjust for variations in the solenoid orifice.
4. New accessories include an inline solenoid shutoff.

We are gathering the Micropore test data and will soon post it. I realize there are some questions since the release of the CE comparison test data just before DEMA. We have reviewed it the test data. Dive Rite is not a European company so we didn’t build the O2ptima to CE specifications. We built a CCR around new technology and based our performance on US Navy standards, something a little closer to home. We were able to build a smaller, more efficient unit than our competitors.Now that we have built a CCR on a unique platform we will start modifications to go for CE approval. The problem is that CE standards are written for older technology, but if CE standards are not updated, we will evaluate the necessary changes to meet the CE directives.

If you want to know about the performance of the O2ptima, just ask the divers using it. I am always available for a dive when you visit North Florida. You dive your unit and I will dive the O2ptima.

Lamar

Work of breathing varies with CCR models. The O2ptima has the shortest breathing loop on the market and because of this we can use smaller hoses. However, with this feature comes more attention to detail. The counterlung must be mounted in the right place to take advantage of the smaller hoses. The T-piece connections and ADV must be located high on the chest just below the shoulder. If you move them any lower on the chest then WOB will increase. If you feel the WOB is too great then adjust the CL higher with the attachment straps. This is critical. Once you get the CL positioned correctly, you will find that you can breathe vertically, horizontally or upside down without a problem.

Lamar