Rebreather World - View Single Post - Some clarification please. What is open exactly?

AD_ward9 · 9th November 2007, 14:12

Thanks Ben, for a very good summary. DEMA was busy, and we are in a conference in Bergen this coming week too. Glad someone managed to post up pictures in the gallery here, as I have just been too busy to do it myself.

To answer the question posed by this thread:

What is Open is the entire safety case. It means Open safety. That means we publish the full test results for every aspect of the rebreather, the methods used exactly, their analysis and how the analysis has been carried out, the verification models themselves, the safety integrity assessment, the MTBF and MTBCF data, the circuit and hardware reviews, the full FMECA, the safety case, important HAZOPs.

The Revolution means compliance with the EN61508 safety standard, to SIL 4 in this case though units which are produced only in small numbers with good control over recall and upgrade would get away with SIL 3.

It refers to an Open Revolution in rebreather safety, not an Open release of a rebreather design for anyone to copy. However, key safety findings and algorithms created in the Open Revolution process have been published and we have stated that we are deliberately not patenting the most important of these in the hope others will take them up (some already have), and improve the safety in the whole industry.

Examples of things others have taken up already are:
1. Using twin injectors to check O2 cells continuously
2. Calibrating on air when the scrubber is open
3. No off switch: switching on with falling PPO2
4. PPO2 control algorithm

Cheers,

Alex

Quote: (Originally Posted by DeepBlueInnovation)

Hi Robert, and welcome to Rebreather World.

I think you have misunderstood the concept of the Open Revolution. The Open Revolution as I understand it is a mark of compliance with the points that you have listed. The deep life rebreather is a unit that is being created to adhere to these standards, it is not an open source project in the Linux model. The documents on the Deep Life website are part of the compliance requirements, with all the requirements being released before the rebreather is released to the public.

send Alex a pm and I am sure he will clarify things for you, although I suspect he will be tied up with DEMA for the next week or so.

It is also common practice to have levels of software available based on what you pay for - with many dive computers/rebreathers a base level of functionality is available with the initial purchase and users may pay to gain the unlock codes for further features. This keeps products affordable to users who are never going to use trimix features etc. It also provides manufacturers with an ongoing revenue stream

Cheers,

Ben.

9th November 2007, 14:12	#3 (permalink)
AD_ward9 So much more to learn Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Jun 2005 Location: Scotland Posts: 1,856	Re: Some clarification please. What is open exactly? Thanks Ben, for a very good summary. DEMA was busy, and we are in a conference in Bergen this coming week too. Glad someone managed to post up pictures in the gallery here, as I have just been too busy to do it myself. To answer the question posed by this thread: What is Open is the entire safety case. It means Open safety. That means we publish the full test results for every aspect of the rebreather, the methods used exactly, their analysis and how the analysis has been carried out, the verification models themselves, the safety integrity assessment, the MTBF and MTBCF data, the circuit and hardware reviews, the full FMECA, the safety case, important HAZOPs. The Revolution means compliance with the EN61508 safety standard, to SIL 4 in this case though units which are produced only in small numbers with good control over recall and upgrade would get away with SIL 3. It refers to an Open Revolution in rebreather safety, not an Open release of a rebreather design for anyone to copy. However, key safety findings and algorithms created in the Open Revolution process have been published and we have stated that we are deliberately not patenting the most important of these in the hope others will take them up (some already have), and improve the safety in the whole industry. Examples of things others have taken up already are: 1. Using twin injectors to check O2 cells continuously 2. Calibrating on air when the scrubber is open 3. No off switch: switching on with falling PPO2 4. PPO2 control algorithm Cheers, Alex Quote: (Originally Posted by DeepBlueInnovation) Hi Robert, and welcome to Rebreather World. I think you have misunderstood the concept of the Open Revolution. The Open Revolution as I understand it is a mark of compliance with the points that you have listed. The deep life rebreather is a unit that is being created to adhere to these standards, it is not an open source project in the Linux model. The documents on the Deep Life website are part of the compliance requirements, with all the requirements being released before the rebreather is released to the public. send Alex a pm and I am sure he will clarify things for you, although I suspect he will be tied up with DEMA for the next week or so. It is also common practice to have levels of software available based on what you pay for - with many dive computers/rebreathers a base level of functionality is available with the initial purchase and users may pay to gain the unlock codes for further features. This keeps products affordable to users who are never going to use trimix features etc. It also provides manufacturers with an ongoing revenue stream Cheers, Ben.
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