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Still young enough to know everything
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Discussion Starter #1
When a manufacturer quotes a flow rate for a regulator in liters per minute, does it mean surface liters or actual liters? As in, is the amount that it can supply based on the mass of the gas, so the volume halves when the pressure doubles, or is it the actual volume, so it can always deliver x liters of gas, no matter what the depth?

Cheers in advance :)
 

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Still young enough to know everything
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Discussion Starter #4
yes yes yes alright you've told me often enough - get a life etc. Pete, I would love to come to Capers and meet you there but I'm diving with my club on Sunday I think and my dad can only have 1 day off at the weekend - the cows get grumpy if he's away too long...
 

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Pete, Sean, nobody likes a smart arse. Do we really need a section of the forum where someone with a legitimate question can get a legitimate answer without your BS?

James, I don't know the answer, but I'll bet a pound to a piece of poo that if you rang Apeks tomorrow morning they would find out and get back to you, or would know there and then. Probably better if you want a good answer to speak to a manufacturer, they will know.

In the meantime, I don't know the answer. And you know what, there's very little to be lost in finding out.

Digs.
 

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aka Chimp 1 or Mavis...
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BS EN 250:2000

BS EN 250:2000 is where you can get a copy but it'll cost you £64 :D

I personally thought it had to deal with density which is why you can breathe He mixes no worries whatever depth, but once you dive air at deep depths, you need something that delivers massive amounts of gas (like Poseidons!)

Regards
 

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Still young enough to know everything
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Discussion Starter #8
BS EN 250:2000

BS EN 250:2000 is where you can get a copy but it'll cost you £64 :D

I personally thought it had to deal with density which is why you can breathe He mixes no worries whatever depth, but once you dive air at deep depths, you need something that delivers massive amounts of gas (like Poseidons!)

Regards
£64??? I wouldn't pay £6.40 :D

In that case, it would suggest that it is to do with the mass of gas rather than volume, so... a Poseidon cyklon has a quoted flow rate of 1250 liters per minute, which means, presuming that the quoted flow rate is when on the surface, that it can deliver approximately 1.5 kg of gas per minute :) I think...
 

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Still young enough to know everything
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Discussion Starter #13
Couple of quid into Morag's fighting fund. For £3 she might let you have a go on her boobs, too. You'll have to ask her politely. Can I be there when you do? I forsee slapping.
Lol ok wait a min
 

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Digger, fair point.

James, I (as in my company) have a subscription to BSOL (British Standard Online), and I have just downloaded BSEN 250:2000 :)

PM me your email and I will email it over, it's a 20 page PDF, about 1.2mb. You can then go through it, and report back to all of us with your findings. Fair??

Obviously, our subscription is fairly tight on who is allowed stuff, I thereby grant you temporary use of my personal copy. This might be outside the user agreement, however, so I might have to request my copy back at some point
 

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Still young enough to know everything
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Discussion Starter #15
Digger, fair point.

James, I (as in my company) have a subscription to BSOL (British Standard Online), and I have just downloaded BSEN 250:2000 :)

PM me your email and I will email it over, it's a 20 page PDF, about 1.2mb. You can then go through it, and report back to all of us with your findings. Fair??
Very fair. will do.
 

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Similar vintage to a REAL Fender Telecaster®
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I've only ever seen flow rates quoted as part of a whole work of breathing do dad... a quick search in Wikipedia turned up the following...

In the European Union the standard EN250:2000 <Respiratory equipment. Open-circuit self-contained compressed air diving apparatus> defines minimum performance standards for "Open-circuit self-contained compressed air diving apparatus".

The standard contains limits on inhalation and exhalation pressures and overall work of breathing. It specifies the following, under test conditions of a breathing rate of 62.5 litres (2.2 cu ft) per minute and an ambient pressure of 6 bars (600 kPa):

* Work of breathing: <3.0 joules per litre
* Peak respiratory pressure: ±25 mbar (±2.5 kPa) (inhalation or exhalation)
* Inhalation work of breathing: <0.3 joule per litre
* Pressure spikes with no measurable positive work of breathing: <10 mbar (1 kPa)
* Pressure spikes with measurable positive work of breathing: <5 mbar (0.5 kPa)

Although a regulator meeting the above limits will supply sufficient air where the first stage feeds a single second stage, it is not necessarily capable of supplying sufficient air in all circumstances when a single first stage feeds two second stages simultaneously.[5]
 
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