Do you still use a SPG with a AI computer?

[npole]

I have seen people diving without an octopus and they haven't been jailed, so I think you'll be safe.
The issue with the computer AI is due to the electronic involved, they doesn't offer the same level of reliability of a physical pressure gauge, especially because there's a wireless connection involved, so if going with a single SPG is acceptable, going with the AI only is not: on a plane you always have a barometric altimeter and (optionally) a GPS... you can fly legally with a baro only, you can't with a GPS only. Said that everyone is free to do whatever he/she want to do.. as along he/she isn't my buddy.

 

[scubadada]

I have seen people diving without an octopus and they haven't been jailed, so I think you'll be safe.
The issue with the computer AI is due to the electronic involved, they doesn't offer the same level of reliability of a physical pressure gauge, especially because there's a wireless connection involved, so if going with a single SPG is acceptable, going with the AI only is not: on a plane you always have a barometric altimeter and (optionally) a GPS... you can fly legally with a baro only, you can't with a GPS only. Said that everyone is free to do whatever he/she want to do.. as along he/she isn't my buddy.

What data do you have that a WAI is less reliable than a SPG?

 

[Ricardo V.]

@npole,
I don't think there is a right or wrong answer to this debate.

I will however politely disagree with your logic that going with the AI only is not acceptable. Not sure what your experience has been on this, but that's completely contrary to what I've been able to do, observe and share over the past 10 years.

My buddy and I both use AI, we don't rely on SPGs and don't plan on doing it.

Never say never, but while the sport of diving offeres many opportunities and surprises, we don't subscribe to the instabuddy plan; however, we won't purposely leave someone out there wanting to dive without a buddy when they just don't have one.

If your skill levels are up to the challenge and you need a buddy, you are welcome to dive with us. BTW, you can bring your SPGs. No problem.

Ricardo

 

[npole]

What data do you have that a WAI is less reliable than a SPG?

There's a clear warning signal icon saying:

"Always use a backup analog submersible pressure gauge as a redundant source of gas pressure information."

It means they have conduct their tests to determine that their equipment isn't safe enough to be used alone. Even without having their data, you can understand yourself that a computer (that could contains software bugs) + a electronic probe + a wireless transmitter is inherently less reliable that a physical instrument, other wise you wouldn't have the above warning.
On the other side, did you ever see the spg instructions asking you to use a computer with AI for redundancy?

 

[npole]

@npole,
I don't think there is a right or wrong answer to this debate.

I think the only data can be provided by the manufacturer, probably after their tests they determined that a wireless probe isn't reliable enough to be considered as a substitute of a mechanical pressure gauge, hence they have been forced to add that disclaimer/warning in their instructions, so if something goes wrong they wouldn't face a possible legal issue.

However, as I mentioned above, due to the nature of the hardware, it's pretty easy to understand that two electronic gadgets that relies on a wireless connection underwater are inherently less reliable than a tube connecting the tank to a piston.

As I said, everyone is entitled to do whatever they want to do.. even diving without fins. I trust the manufacturer.

 

[Trailboss123]

I have been diving with an AI computer with a transmitter for many years and have yet to lose a dive or have to go to redundancy-- I chose it in order to eliminate an additional hose and check everything from my wrist. That being said, I have always run it with a back up computer that is compatible with the same transmitter, which I attach to a D-ring for redundancy and I have an analog hosed SPG in my save a dive kit, which I keep in my car for shore dives or in a bag while on boat or live-aboard diving.

 

[CWK]

According to Padi, "An SPG can either be a mechanical gauge connected by a hose that reads the pressure in bar (metric) or psi (imperial, pounds per square inch) in your tank, or it may be built into your dive computer." from SPG (SUBMERSIBLE PRESSURE GAUGE)

The "AI" is a SPG that has a bluetooth connectrion and uses the dive computer to display the information. It is not so much SPG and AI, as analogue SPG and digital SPG.

A SPG has multiple parts that can fail, and different failures have different consequences that may require different kinds of redundancies to safeguard against. For example, a crimp failure on the SPG's high pressure hose may have quite serious consequences for which the safeguard may be an alternative air source. Therefore a pony is a valid redundancy against this type of SPG failure.

Everyone here is certified to dive and everyone does different types of diving. For my type of diving I prioritise a pony above a redundant SPG. But the diver who dives with redundant SPGs to safeguard against low tank fills has an equally valid point of view.

 

[scubadada]

There's a clear warning signal icon saying:

"Always use a backup analog submersible pressure gauge as a redundant source of gas pressure information."

It means they have conduct their tests to determine that their equipment isn't safe enough to be used alone. Even without having their data, you can understand yourself that a computer (that could contains software bugs) + a electronic probe + a wireless transmitter is inherently less reliable that a physical instrument, other wise you wouldn't have the above warning.
On the other side, did you ever see the spg instructions asking you to use a computer with AI for redundancy?

Sorry, not based in reality, good luck

 

[CWK]

Manufacturers try to cover their posteriors. An example from the Liquivision LYNX Air Integrated Dive Computer User Manual

WARNING – ELECTRONICS CAN FAIL – ALWAYS CARRY BACKUP
The LYNX dive computer hardware and T1, U-2 and L1 Transmitter hardware will eventually fail, like any electronic equipment whose components mature and age. If they fail during your dive, they can stop providing you with critical information.
You must have a plan to handle the failure of the LYNX dive computer or the T1, U-2 or L1 Transmitters during your dive. You should carry backup instruments, including a depth gauge, submersible pressure gauge, digital bottom timer or dive watch, a compass, and have access to decompression tables. Do not risk your life on only one source of information.


How many divers have backup depth gauge, submersible pressure gauge, digital bottom timer or dive watch, a compass, and decompression tables as a backup for their dive computer?

 

[MargaritaMike]

How many divers have backup depth gauge, submersible pressure gauge, digital bottom timer or dive watch, a compass, and decompression tables as a backup for their dive computer?

I know of one. (most pieces of equipment are in "save-a-dive" kit/bag)
Cheers - M²