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

[Norrm]

In my parts bag, which goes with me wherever I dive, whether it's a local shore dive, or off my boat, or to a distant tropical location, I carry along with spare mask and fin straps, computer batteries, tools to swap hoses, seasickness, headache and sinus meds, and a variety of zip ties, O-rings, bungees. and compact 1st and second stage regulators. By compact I mean "about as small as you can get". Sherwood Magnum and Dacor Viper are two such 2nd stages that are good for extra parts bags.There are a variety of 1st stage regs that are on the smallish side and weigh a bit less.

I've had one 1st stage blow a HP seal (after a recent service) and another with IP creep cause a freeflow in my octo regulator in the middle of a weeklong dive trip. In both cases I quickly swapped the hoses onto my spare 1st stage. One one occasion my girlfriend was sucking water into her second stage and another time my sister got an unstoppable freeflow in her octo reg. I quickly swapped out my spare 2nd stage. I don't depend on a boat charter to have these things. You just never know, and older gear is inexpensive and reliable and not a big deal to carry around.

 

[rhwestfall]

I think it depends on your destination. If you are going somewhere you can't buy, rent, or borrow a regulator set it may be worth thinking about.

^^^^^ This

 

[broncobowsher]

I've had 2 fail. One was an old junker I used for filling car tires. Probably 40 years old, probably never serviced in it's life. Luckily had an OPV that kept the hose from blowing up. The other was a year old Apeks that tested perfect the day before but at the pool for a class had an IP creep. Had a same day rebuild that cost nearly as much as the reg. Looked perfect inside, super clean, but was bad IP creep. Rebuild fixed it. Finished class.

For a local day trip I don't bother with a spare. If a first stage goes out again, that is my cue to stay out of the water that day. But for any trip that involves sleeping away from my own bed, there is a spare.

Was in Truk earlier this month. A hanging deco bottle popped a 1st stage. My spare was put into service.

So they do fail. Old and new. The old one, not surprised. No name on it. Looked like crap inside. Just tossed it. The new ones, neither were lacking service, nor just out of service and were in otherwise good condition.

This doesn't count environmental diaphragm that hemroged into a golf ball during the dive. That one still functioned just fine.

So I have seen them fail. Mine and others. Generally for no good reason. But you also have to balance in how much spares you are willing to bring. By no means would I call it failure prone. They generally do very good. My 40 year old one that finally went is good proof that they can often be ignored for decades and still work, at least up to a point.

 

[divezonescuba]

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.

 

[Couv]

I haven't seen a first stage fail on a trip-but stuff happens. I have seen 2 tanks (separate trips) fall over and disable the first stage, and 1 first stage left to soak with no dust cap. Fortunately none were mine. Other than that I've seen 2 first stages (1 GSD, 1 Dacor 950) fail open with resulting runaway IP after long periods of non use.

 

[tbone1004]

Hello,

in this thread:
First time reg buyer: some questions

@tbone1004 wrote:



@tbone1004 thanks for you advice. I am curious, you wrote" First stages are unpredictable little buggers". This is a relative statement. Just how unreliable are first stages in your opinion? What do you think the failure rate is? Do Deep6 first stages fail in a way that is not fail safe(some would say that ACD first stages could fail in a way that is not fail safe as they close).

Please know that I am not being provocative as I am trying to decide which Deep6 set up to buy yet I am thinking ....really? .... in 100 dive trips(with proper maintenance) of a week long with 20 dives per trip, what would the failure rate be? in my VERY inexperienced mind, I would think it would be less than 1% over that total sample size. Maybe others could weigh in what would be the expected failure rate of first stages? Buying a spare first stage is like buying an insurance policy, yet since one could always rent(unless in remote area) a regulator if need be, one would want to weigh all the costs of buying(and carrying around) a spare first stage.

Thanks for any input.

I'm teaching now so I haven't read the previous 3 pages so I'm sure it's been said, but just in case.

They're not inherently unreliable, but they are more unreliable than second stages.
Failure rate is very small.
They don't fail in any strange or bad ways.

The issue with failure is mainly right after service, or as the regs start to get up in years and then get IP creep. This can also be a sudden onset if/when the soft parts fail. Much better IMO to have the spare and not have to rent, but if you are OK with renting, then it's an insurance policy you may not be interested in. I like my regs, so don't want to deal with rentals, so I carry a spare. That said, a lot of the reason I talk about it is the nonsense spewed about being able to get service anywhere in the world as a reason to buy Scubapro or Aqualung. That is not realistic and you will lose at least a day of diving as a result, as well as spend an arm and a leg for rush service which puts you at the highest risk of having another failure as a result of service *which as mentioned above is when most of them happen*.
Your options are basically to rent, or carry a first stage. If the option is rent, then you have to risk whether you will lose out on the rest of that days diving if the boat doesn't have a spare. A liveaboard will have a spare on board, but some other boats may not. You can swap the hoses to another first stage in less than 5 minutes and not miss a dive. If they have a spare, then it's no big deal, if they don't, then you're done until you can get one.

 

[rsingler]

As noted above, your spare reg will always help out some hapless fellow whose long-ago serviced reg fails.
For me, once in 30 years. But it was a week-long expensive trip to Bonaire. I was glad when the HP o-ring blew on a recently serviced and tested first stage that it was just a quick swap to my spare.
A molding flaw in the HP seat o-ring:

 

[johndiver999]

I would try to bring one complete spare rig (minus the octopus).

First stages are less likely to fail then second stages or hoses etc. As already mentioned, damage from falling, a hose leaking, an spg flooding and second stages can get smashed by a falling tank and second stages seem to get out of adjustment more often than first stages fail, computers can flood or fail etc. An inexpensive back up rig seems like a smart option if you are spending a bunch on a trip.. Maybe even borrow a friend's reg for a week if they aren't using it?

 

[Bigbella]

I always carry redundant equipment into the field, especially to foreign countries, along with tools; first and second stage kits, to break things down, should that ever be necessary. That being said, I have never experienced a first stage failure -- knock on brass and nitrile o-rings . . .

 

[DeepSeaExplorer]

As noted above, your spare reg will always help out some hapless fellow whose long-ago serviced reg fails.
For me, once in 30 years. But it was a week-long expensive trip to Bonaire. I was glad when the HP o-ring blew on a recently serviced and tested first stage that it was just a quick swap to my spare.
A molding flaw in the HP seat o-ring:
View attachment 550732

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.