Failure rate of first stages? what is real need for a spare first stage on a trip

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I usually travel with conshelf 14 seconds, not the best breathers but the boat could fall on them and they'd still work. Seat can be flipped, no special tools or gauges required. Dead nuts simple.

Most first stage failures I believe are the hp seat or balance chamber O rings. On an FSR, I know there are others too, all can be accessed without total disassembly, only a hex key required. Justification over.
 
This is why I never get gear serviced before a trip or a big dive.

I would trust a reg that’s overdue for service more than a reg that was just serviced, especially if I’ve been diving that reg a lot.

I wouldn’t trust a newly serviced reg until I get at least 1/2 a dozen dives on it.
Except, as the Northern California Service Center for Poseidon, I tend to trust my own service, lol! That's why I showed the freak HP seat o-ring failure. But you're right... if I'd dived it a half dozen times before taking it to Bonaire, I would likely have discovered the issue.
But I still bring a spare reg set along everywhere.
 
I have had first stages fail twice. In one instance, I had been using the first stage all week. It failed on around the fourth day. Both were the same model regulator. I think it is a design flaw with a spring that is too weak.

Whenever we go on a shop trip, I carry at least one extra first and second stage, hp hose, gauge, Lp hose with inflator adapter, inflator, and a toolkit.

Some people have thought it was overkill. However, on several trips, I have worked on several divers gear over the course of the trip. I have also ended up working on other people’s gear not with our group just to be nice.

On one trip to Cozumel, the resort dive shop told a lady not in our group that it would take two days for them to fix something. We had her setup in 10 minutes.

If you go with a shop that does group trips, you might not need to bring any extra parts at all.
So the answer is to bring a spare divezonescuba.
 
I had a sudden failure of a Mares MR-22 first dive of a two week trip in Hawaii. The HP seat face chipped under the orifice. I opted to buy a Aqualung Titan (v1), which was fortuitous since I've since settled on Titans/Conshelfs for my mini-fleet. They share the same HP seat, and also with the Mares, and I've seen several of that style, including Dacor, with chipped/cracked faces. So sudden failures seem possible. I've also seen regs destroyed by tanks falling, so taking spare hardware and hoses seems like cheap insurance compared to the hassle and cost of renting gear.
 
I've had a 1st stage Apeks DS4 blow out while gearing up for a local shore dive. Did not have a spare, went home dry.

I had a 2nd stage dropped and crushed (by a "helpful" hotel bellhop) on my way to a remote week long trip. Did not have a spare, had to buy one at an inflated price to save the trip.

Now I always carry an extra 1st/2nd/Spg set with me all the time.
 
A hanging deco bottle popped a 1st stage.
I've had a 1st stage Apeks DS4 blow out

What do the above terms (popped & blowout) mean? What are the:
Causes.
Symptoms.
Treatment.
Prevention.

Thx
 
I alway bring a spare reg set when diving locally or traveling, I like how I’ve set my stuff up and don’t want to mess around if there is a problem. I have had first stage failures on new regs, I rarely buy new anymore, primary travel reg is a titanium Atomic, and my current back up is a Zeagle F8, both yoke for ease of use where I don’t have my own tanks.
Me too. A complete spare working set that can interchange with mine in every way.
 
Except, as the Northern California Service Center for Poseidon, I tend to trust my own service, lol! That's why I showed the freak HP seat o-ring failure. But you're right... if I'd dived it a half dozen times before taking it to Bonaire, I would likely have discovered the issue.
But I still bring a spare reg set along everywhere.
We repair cars, tractors and other machinery. The part I trust the least in any of them is the one we just installed. The others are proven.
 
I've witnessed an Aqualung diaphragm first stage catastrophically blow its HP seat at 40m on the President Coolidge in Vanuatu... the diver was enveloped in a ball of bubbles as the tank drained in a few moments.
Fortunately he kept his cool and buddy breathed off the guide up to the deco stop.
Apparently the HP seat polymer material delaminated from its carrier (!)

I've personally experienced the HP seat 'fail to regulate IP' on my Kraken DH reg and vent air at 200psi through the octo... only at about 20m, apparently a faulty batch of HP seats, a couple of others reported.
Happened on a LOB in East New Britain, PNG, I always carry a spare single hose reg set so switched to it and fortunately didn't lose a dive.

I also carry a fairly comprehensive stock of cable ties, common o-rings (esp those tiny -003 HP swivel ones!), BC inflator kit and tool, silicone grease etc and have either used them myself or helped out other divers on pretty much every remote area LOB I've been on.

A spare reg set is very good insurance on any dive trip, whether local or remote area LOB.
 
https://www.shearwater.com/products/swift/

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