Sidemount Freeflow Drill

[GLightcap]

You might want to refresh the drill/exercise - you should at least check the depressurized 1st stage handwheel and tighten if possible. Also LOOK at what is broken and where the bubbles are coming from. For instance, a HP hose failure can feel like a significant amount of bubbles but it's an insignificant amount of gas. Which is important to know. Don't just spin it off and on expecting resolution

The 2nd stage depressurizing is not important, water goes into that space anyway. It won't reverse up the hose.

Thank you for the reply rjack321. It was not my intention to fully describe the valve drill, i am intimately familiar with the procedures. My concern is that the manufacturer warns that the regulator cannot be submerged unless pressurized. This is definately a negative selling point and a reason why many people choose not to purchase Atomic regulators, so I don't think they would make that warning unless it was absolutely necessary. Thanks again for your input!

 

[GLightcap]

I would keep breathing the leaking side and conserve the good side to get out… ( my redundancy) i don’t understand your question actually.


Are you concerned about the water exposure to reg internals during drills? It’s the price i pay to play.

Thanks for your reply girlwithbigtanks. Yes my concern is with what could happen by violating the manufacturer's warning about having the regulator submerged while not pressurized.

 

[GLightcap]

When you’ve a depressurised regulator it is possible for the first stage to loosen off from the valve seat and water to get into the valve and first stage. When powered up you sometimes see a cloud of bubbles spewing out of the valve when you need to shut down the valve and tighten it, then try again. Water will then run though the first and second stage. However, the dry gas will quickly dry out the first stage and second stage, especially if purging.

Regs are designed and built for this. They don’t need servicing after. Unless you want to.

Thank you for the reply Wibble. The manufacturer is the one warning to never allow the regulator to be submerged when not pressurized.

 

[GLightcap]

During free flow drills you're only depressurizing the reg for a second or two. Not an issue. Also in real life you'd be feathering the valve and not leaving it off for more than a second. I get 2-3 breaths out of the long hose when the reg is shut down. As I start the 3rd breath I crack the valve open and pressurize it. I did a 20 minute dive at 110ft in Gilboa doing this just for practice.
What's more of a concern is when I see someone do drills and because the reg is not pressurized it may turn slightly on the valve. Then I see people with the valve on try to re-orient the 1st stage the way they had it. This is a good way to loosen the DIN connection. If you don't catch it after the dive, it can result in a leak where the DIN housing connects to the reg body. Do your drill. As soon as you feel the hose start to go limp, crack the valve back open.
To simulate switching to the back up, as soon as you feel the hose go limp, crack the valve open and switch to the other reg. This way it's not hanging there with no pressure on it.
In real life you wouldn't care. An OOA means you plan on rebuilding the 1st stage.
Same as when we do reg swaps underwater to a stage. I have a couple 1st stages for this. Remove the reg from one bottle and swap it to another. 1st couple breaths will be a little wet, then it's fine. At the end of the training weekend I plan to be rebuilding that reg. I don't put an spg on it because spg's are expensive.
1st stage kits are cheap.

Thank you for your reply

Jim Lapenta!​

 

[Wibble]

Thank you for the reply Wibble. The manufacturer is the one warning to never allow the regulator to be submerged when not pressurized.

In reality, decent quality regulators should cope with some flooding. This is why the regs should be serviced as some parts may corrode such as the filters. However, if it’s used and not left wet, it’s probably not going to be adversely affected.

Note the use of probably, should, etc. There’s a risk and it’s your decision.

So, what’s the main benefit from sidemount…? Redundancy, ease of switching, etc.


In multiple gas diving — aka accelerated decompression— it’s normal to power up the decompression stage regulators to check they work and hold pressure then close the valve before jumping in (you don’t want to breathe the oxygen rich gas at depth as it’ll kill you). Inevitably the regs will leak if knocked/purged or if the second stage dribbles/free flows. One periodically checks but it’s quite common for the reg to flood. It doesn’t seem to create long term problems, certainly in my experience anyway.

FYI all my decompression/stage/bailout regulators are Apeks DST or DS4. These are very common in technical diving — certainty the most common regulators I see on all dive boats I’ve been on. I use those as they’re reliable and 'just work'.

 

[rjack321]

Thank you for the reply rjack321. It was not my intention to fully describe the valve drill, i am intimately familiar with the procedures. My concern is that the manufacturer warns that the regulator cannot be submerged unless pressurized. This is definately a negative selling point and a reason why many people choose not to purchase Atomic regulators, so I don't think they would make that warning unless it was absolutely necessary. Thanks again for your input!

You're splitting hairs. Water gets into 2nd stages with normal LP seats too. The next time you pressurize that reg and tap the purge it blows out.

 

[rjack321]

double post

 

[GLightcap]

In reality, decent quality regulators should cope with some flooding. This is why the regs should be serviced as some parts may corrode such as the filters. However, if it’s used and not left wet, it’s probably not going to be adversely affected.

Note the use of probably, should, etc. There’s a risk and it’s your decision.

So, what’s the main benefit from sidemount…? Redundancy, ease of switching, etc.


In multiple gas diving — aka accelerated decompression— it’s normal to power up the regulators to check it then close the valve before jumping in (you don’t want to breathe the oxygen rich gas at depth as it’ll kill you). Inevitably the regs will leak if knocked/purged or if the second stage dribbles/free flows. One periodically checks but it’s quite common for the reg to flood. It doesn’t seem to create long term problems, certainly in my experience anyway.

Thank you for the thoughtful reply.

 

[GLightcap]

You're splitting hairs. Water gets into 2nd stages with normal LP seats too. The next time you pressurize that reg and tap the purge it blows out.

I am just repeating what the manufacturer is saying. Their seat saving orifice retracts away from the seat when not pressurized which prevents damage during storage. This is a unique Atomic design and because of this open seal, the manufacturer warns not to submerge the regulator when unpressurized because water could pass through and get into the first stage. The Scubapro regulators remain sealed when not pressurized preventing this water intrusion into the first stage. The aforementioned information is commonly known and I am not comfortable disregaurding Atomic's warning (I'm not saying you are wrong, but I don't personally have the expertise or knowledge to assess the risk of water infiltration into the first stage). In my original question I am trying to determine if I can follow the manufacturer's instructions without significantly changing what has become muscle memory such as the valve drill.

 

[Alaskan Scuba Dude]

I am trying to decide between the Atomic M1 and Scubapro MK25 EVO/A700 regulators and I was leaning towards Atomic until I realized the seat saving design prevents submerging the second stage unless it is pressurized. I'm not concerned about cleaning but when I was taught how to handle a major leak or freeflow in sidemount I was taught to signal, shut down tank, breath the tank down, switch to the other regulator, slowly reopen the leaking tank and if it is no longer leaking you carry on. My question is, is it really necessary to breath down the leaking tank? I don't remember if I was taught this but I thought you breathed it down to depressurize it and then when you turn the tank back on, in some instances the depressurizing could fix the problem. I think in a real world problem the Atomic regulator would perform fine even if some water made its way into the first stage, and then i would just have it serviced. But when I do these drills regularly should i be concerned about breathing the Atomic regulators down while submerged? Thanks in advance for you input!

Would like opinions on the Scubapro MK25 EVO/A700 regulators. I've heard the diaphragm vibrates at depth when using air. Would also like to know how they perform using Trimix.