How often do RV propane cylinders and tanks need to be re-certified?

[Wayne]

Our portable propane cylinders need to be re-certified after a certain number of years, so I started looking for the answer. I found that portable cylinders and tanks are a much different beast.

Tanks that are permanently affixed to trailers are referred to as American Society of Mechanical Engineers (ASME) tanks and do not require testing. Although ASME tanks do not require testing, they should be inspected for excessive pitting or physical damage.

Portable cylinders are those that are not permanently affixed to your trailer. Portable cylinders are referred to as "DOT Cylinders" and are regulated by 49 CFR 180.209(e). DOT cylinders are also found on outdoor grills, space heaters, etc.

Federal Code of Regulations 49 CFR 180.209(e) table below shows how often portable cylinders need to be tested. The link provided has more detail and references to many other regulations.

https://www.ecfr.gov/current/title-...bchapter-C/part-180/subpart-C/section-180.209

Specification under which cylinder was made	Minimum test pressure (psig)2	Requalification period (years)
3	3000 psig	5.
3A, 3AA	5/3 times service pressure, except non-corrosive service	5, 10, or 12
3AL	5/3 times service pressure	5 or 12
3AX, 3AAX	5/3 times service pressure	5.
3B, 3BN	2 times service pressure	5 or 10
3E	Test not required
3HT	5/3 times service pressure	3
3T	5/3 times service pressure	5.
4AA480	2 times service pressure	5 or 10
4B, 4BA, 4BW, 4B–240ET	2 times service pressure, except non-corrosive service	5, 7, 10, or 12
4D, 4DA, 4DS	2 times service pressure	5.
4E	2 times service pressure, except non-corrosive service	5, 10, or 12
4L	Test not required
8, 8AL		10 or 20
Exemption or special permit cylinder	See current exemption or special permit	See current exemption or special permit.
Foreign cylinder	As marked on cylinder, but not less than5⁄3 of any service or working pressure marking	5

Mine is a type 4BW and has to be tested per these terms:

Cylinders in non-corrosive gas service. A cylinder made in conformance with DOT Specifications 4B, 4BA, 4BW, or 4E protected externally by a suitable corrosion-resistant coating and used exclusively for non-corrosive gas that is commercially free from corroding components may be requalified by volumetric expansion testing every 12 years instead of every 5 years. As an alternative, the cylinder may be subjected to a proof pressure test at least two times the marked service pressure, but this latter type of test must be repeated every 10 years after expiration of the initial 12-year period. When subjected to a proof pressure test, as prescribed in CGA C–1, the cylinder must be carefully examined under test pressure and removed from service if a leak or defect is found.

 

[ctechbob]

Talk about something I've never given any thought to. Having 20# cylinders, I'll probably just swap them out in 10 years at the cylinder exchange.

Has me curious though to look at the several of them I have sitting around that I've collected over the years. I probably have 4 more not including the 2 that are on the camper.

 

[MSCH]

pretty sure removable propane tanks are 10 year. the guys that refill them usually check..

as far as 20 pounders go, just exchange them. they are dime a dozen.

 

[Wayne]

pretty sure removable propane tanks are 10 year.

They could be or 5 or 7 or 12

The chart and all the references will explain exactly when a tank needs to be tested, but it's quite a bit of reading and referencing and you have to be able to read the type on the cylinder.

 

[dnewton3]

I had some larger DOT 30# cylinders (for extended service), and my problem is that once the initial certification expired, I couldn't find anyone that knew about re-cert services. I called several different places; no joy. I would have preferred to keep these; they were in good shape. Unfortunately, after a few attempts at trying to get them filled, no one would fill them without the re-cert (which is understandable), and no one could be found to test them. So they ended up being dead weight.

I ended up just converting down to typical 20# DOT tanks, and exchanging them easily at any local store.

 

[Wayne]

I had some larger DOT 30# cylinders (for extended service), and my problem is that once the initial certification expired, I couldn't find anyone that knew about re-cert services.

Mine are 40# cylinders and I hope I can find someone to test them, wouldn't want to throw them away.

 

[ctechbob]

Mine are 40# cylinders and I hope I can find someone to test them, wouldn't want to throw them away.

Sounds like you're in for a lot of googling and phone calls. I'd hate to throw those away as well.

I still need to look at my 'spares' I have laying around. Guess if they're getting up there in age I'll just go swap them.

 

[dnewton3]

Mine are 40# cylinders and I hope I can find someone to test them, wouldn't want to throw them away.

Yeah, it was painful to turn them in. They were in perfect shape. And yet, "expired" and no one would fill them.
Couldn't find anyone who would recert them anywhere near me.
True bummer.

Prepare yourself ... It's best to see the storm coming and get ready for the impending doom.