accident statistic for Mares Horizon

[Bartlomiej]

I'm terrified of mistakes in training materials (for example in calculating oxygen toxicity). If a student does not have knowledge about basics of tec diving he could remember incorrect information (which could be the reason for the accident).
Mares Unit also not so safe as it is advertised.
For example, if you by mistake open deco tank valve. Deco tank 1st stage LP is set to 12 bar, so hot nitrox will go into breathing loop, the computer shows danger information and order to change to OC. But hot nitrox with 12 bar also go to 1st of the bottom tank and in 2nd stage of the bottom tank will be also higher oxygen mix. The suggested deco mix is 70%, so if you will be above 12m you will be in great trouble.
Do you have any statistics about accidents in this unit.

 

[Pedro Burrito]

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[jfe]

Your post is not very clear, however from what I've seen from the Horizon, is that it functions a lot like the old Hollis Explorer i.e. it's fed from a pre-determined nitrox mix that you calculate according to your m.o.d, something everyone learns in their nitrox class.
If what you refer to as deco tank, I do not think it's technically correct and you may be referring to a bailout. Why would that be hot and inject at 12 bar? If you have no training in deco, why would you consider it to start with and second I'm not sure this unit is intended for technical profiles, it's according to what I've seen a recreational unit and you should stay within recreational limits. But hey, only the authorised trainers will be able to answer your concerns correctly, don't overthink it but see a trained instructor who will give you correct information.

 

[Bartlomiej]

True, in this unit you set the expected percent of oxygen in the loop. According to training materials if you want do deco dive with accelerated decompression you bring two tanks/bailout. On each tanks you have 1st connected with the manifold with LP. On deco stop you open the valve of deco tank (due to 1st is set to ~12bar, deco gas push out lower nitrox from manifold. What important manifold is connected with the first stage of bottom tank/bailout (bailout has emergency 2st, but is also used by reb). Deco nitrox goes by manifold to 1st of the bottom tank and due to this +2bar go inside to LP chamber. When you want to breathe from the emergency 2nd stage of the bottom cylinder in real you will breathe with nitrox from deco cylinder.

 

[rjack321]

Do you have any statistics about accidents in this unit.

Have not heard of a single accident on this unit. But, that doesn't mean one hasn't happened. It is also unclear how many have actually been sold, at least around me it is not popular at all and I don't know of even a one person owning one.

 

[Dusty123]

Why not just finish your deco on open circuit if your that worried about it? Its not like you will need much gas to do so in the realms of what this thing is intended for. And by that I mean a completely independent bailout not plugged into the horizon.

 

[Bartlomiej]

Dusty123, You do not understand how this unit work. In short words, If you by mistake open deco tank valve you will have gas from this tank even in the bottom bailout regulator. This "feater" is that is most scary for me.

According to the image, if you open dec tank then 12bar EAN70 moved out EAN32 from manifold and the first stage of the tank with EAN32. If you breathe with a regulator from EAN32 tank you will breathe EAN70.

 

[Wibble]

Isn’t the advanced decompression ‘feature', with the rich gas, for advanced applications. Novices are restricted to using bottom gas only.

Advanced diving requires advanced skills. These skills are earned through training and practice. The onus is then on the diver to not be a **** as their life depends on those skills.

 

[DiveClimbRide]

Only a problem if you somehow manage to accidently open your second tank and ignore the numerous warnings about high pp02 that will pop up on the display not to mention the loud as **** beeping from the computer. Additionally since this is an active semiclosed rebreather part of your training to deal with high pp02 will involve checking if the deco tank is off.

 

[broncobowsher]

I have to ask the OP, Are you trained in the Horizon, or just read the materials on it?

I really don't see how this is any more of an issue than any other gas switch on open circuit. Probably safer since PPO2 is monitored.

Accelerated deco is at the top end of what the Horizon is marketed to do. For a basic recreational rebreather, there isn't a second gas to be an issue.