Check IP Every Dive

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The military also prescribes checking tire pressure and fluid levels daily during pre-op checks. It can't hurt, especially when others may also be using the same gear.

I check mine at least every few months, before any trips, and at any indication of a problem. I always carry a spare regulator when I go diving. I often take a cheap IP gauge with me for troubleshooting problems, usually on other diver's gear.
 
I'm not sure rec divers even know how.
It's not something they teach in most Open Water or even Advanced Open Water scuba courses.

I am curious....could you enlighten me so I'm a more educated diver.
Thanks in advance....:)

Every day is a bit much but it would be good if very diver knew how to check their regs IP. I check mine before any major trip or if there seems to be a problem. Checking it is very easy, just get a gauge (like the one in the LP link below) and attache it where your BC lp inflator would normally go, open the tank valve and cycle one of the second stages a couple of times, then read the meter. For most regs the IP should be in 135 to 145 psi range. The actual value is not so important as long as it's in the correct range. What is important is that it stays at the same value every time and does not "creep". Creep is when the IP very quickly gets to a value- like it should- then slowly creeps up to a higher value or does not stop at all. On simple unbalanced piston regs like the Scubapro MK-2, the IP will vary with tank pressure so tank pressure has to be taken into account if your reg is an unbalanced design but it still should not creep. An IP that jumps from one value to another when a second stage is purged (the needle should swing during the breathing cycle but quickly return to the previous value) or creep are signs that service is needed.

This gauge is usually on Ebay for around $20.

Intermediate Pressure Gauge Plugs Into The BCD Quick Disconnect Hose
 
although it is a little over the top, you can never be too careful! we have an easy set up that plugs right into your lp (low-pressure) hose that you can make yourself. go to grainger's and purchase a liquid filled pressure gauge. attach an lp adapter to the gauge. now you can check your pressure in a click. what you want to watch for is to see what the initial pressure is (depends on the make of your reg) and watch to see if it starts to creep. if you see it creep, your first stage is due for an overhaul!

hope this helps.
 
I agree with Herman that the value of the test lies not in the value but rather in how solid the lock up is and the abscence of any IP creep.

I recommend divers do some basic pre-dive checks.

1. Hook the reg up to the tank. Before you turn on the tank valve, try to inhale from the reg. You should not get any air or hear any leaks. If the reg fails this vaccuum check you probably have a leak in the exhaust valve, the diaphragm or in one of the o-rings sealing the case or through a crackin the case itself.

2. Pressurize the reg. Depress the purge slightly. If you have to depress it more than a very slight amount before airflow starts, the lever may be improperly adjusted, reducing the working range of the valve and the flow rate of the reg.

3. Breath off the reg to ensure it breathe normally and does not freeflow even slightly after the last breathe.

4. leave the reg sit in this pressurized condition for a few minutes. If the second stage begins freeflowing slightly immediately after you stop inhaling from it, it is most likely in need of adjustment or annual service due to improper second stage orifice adjustment or excessive LP seat wear.

If the primary or octo begins freeflowing slightly a few seconds to a few minutes after you last breathed off it, it indicates IP creep - most commonly caused by a leaking HP seat or damaged first stage orifice.

This check does basically part of what you can check with an IP gauge, it just takes longer and does not give you the same amount of information that the needle does on an IP gauge in terms of IP drop, initial swing/lockup - just IP creep over time.

5. If the reg passes number 4, turn the tank valve off but do not purge the reg. Note the SPG pressure and leaving it undisturbed come back in 5 or 10 minutes. The SPG pressure should be close to the original value. A drop of 200-400 psi is no big deal, but a large drop in pressure indicates something is leaking beyond the normal limits. If the leak is so fast you can see the needle drop just looking at it, the leak is probably large enough to warrant fixing before you dive.

Common areas for leaks are the o-rings on the hoses connecting stages and accessories to the first stage and the o-rings on the first stage plugs. These are normally easy to fix with a wrench and a suitable o-ring in a dive kit.

Other less common possibilities are the HP swivel in the end of the SPG hose, or a leak in one of the hoses. These two have the potential to get worse fairly quickly. Another even less common failure is a leak in one of the static or dynamic HP o-rings in the first stage, and this bodes ill for the health of the reg. These last three all have the potential to be bad news and it would be prudent to cancel the dive until the problem is fixed.

*Sherwood first stages use an air bleed system and a sslow leak in the first stage is normal, so they will never pass #5.
 
Nice checklist. I would like to update the checklist that we already started with some of your ideas, or if you would like to make some comments to the list up above, it would be good.

I use your item 5 all the time myself, but I forgot to include it in the list as an easier alternate to a bubble check. Actually the bubble check would only follow that test if one wanted to isolate the location of the leak.

I will send you an email in a bit.

Here is the list I am referring to:
http://www.scubaboard.com/forums/regulators/260452-regulator-checklist-inspection.html
 
https://www.shearwater.com/products/peregrine/

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