Here we go again...PST tanks marked E9791/SP9791

[Ted Judah]

I snapped this at my LDS. Unfortunately I didn’t think to photograph the whole thing.

 

[Eric Sedletzky]

Just curious, why aren’t LP 3AA tanks subject to a permit renewal like this one?

 

[DeepSeaExplorer]

Because they are low pressure. The permit is for high pressure tanks. The whole thing is odd.

 

[greeniguana]

I snapped this at my LDS. Unfortunately I didn’t think to photograph the whole thing.

Appears to be a printout of the the PSI-PCI "special bulletin".

Industry Bulletin: Status of the Special Permit 9791 - DiveNewswire

PSI-PCI would like to provide the following factual information related to the expiration of Special Permit 9791 (marked on cylinders as either E9791 or SP9791). The Special Permit (SP) is expired as of 9/30/22. This means that any cylinder stamped with that SP9791 or E9791 is no longer valid...

www.divenewswire.com

 

[rjack321]

Does anyone know if these tanks can still be filled in Canada?

PST SP 9791 cylinders have never been legal to fill or hydro in Canada.

 

[rjack321]

Just curious, why aren’t LP 3AA tanks subject to a permit renewal like this one?

Because they are made to an actual DOT specification (3AA) not under a special exemption.

Because they are low pressure. The permit is for high pressure tanks. The whole thing is odd.

It has nothing to do with their pressure rating. 3AA tanks exist in a vast array of pressure ratings, up to 6000psi or more. I have some 3AA 3400psi plus rated ones in my garage right now - they are not scuba cylinders.

 

[Eric Sedletzky]

Because they are made to an actual DOT specification (3AA) not under a special exemption.

It has nothing to do with their pressure rating. 3AA tanks exist in a vast array of pressure ratings, up to 6000psi or more. I have some 3AA 3400psi plus rated ones in my garage right now - they are not scuba cylinders.

I learn something every day.
So if a person wanted to hedge themselves against this sort of thing in the future then they should buy or collect 3AA tanks and that would be good insurance that they will be in service for life?
Provided they pass hydro of course.

 

[Tracy]

I learn something every day.
So if a person wanted to hedge themselves against this sort of thing in the future then they should buy or collect 3AA tanks and that would be good insurance that they will be in service for life?
Provided they pass hydro of course.

Yes, but there are cons to those as well depending on your location.
If you are cave diving in north Florida, by all means buy the 3aa tanks, they all get filled to the same pressure.

If you are in podunk kansas, you aren't getting 3600 psi in your lp85s.
While there are the occasional 3500ish psi 3aa scuba cylinders floating around, they are very heavy. Fine for single tanks, but make horrible doubles.

 

[Bob DBF]

I learn something every day.
So if a person wanted to hedge themselves against this sort of thing in the future then they should buy or collect 3AA tanks and that would be good insurance that they will be in service for life?
Provided they pass hydro of course.

Yeah, go pick up some Faber MP tanks and take some lead off your belt.

Manufacturer & Nominal Capacity	Service pressure, psi	Actual air capacity, ft3	Outer diameter, in	Length without valve, in	Empty weight, lbs (w/o valve)	Buoyancy Empty, lbs (w/valve)	Buoyancy Full, lbs (w/valve)

Faber 100

3180 +10%

100

7.25

24.01

38.7

-7.26

-14.76

Faber 120

3180 +10%

120

7.25

28.64

48.3

-7.22

-16.22

 

[rob.mwpropane]

Yes, but there are cons to those as well depending on your location.
If you are cave diving in north Florida, by all means buy the 3aa tanks, they all get filled to the same pressure.

If you are in podunk kansas, you aren't getting 3600 psi in your lp85s.
While there are the occasional 3500ish psi 3aa scuba cylinders floating around, they are very heavy. Fine for single tanks, but make horrible doubles.

You just offended all 3 people in podunk Kansas