Metric versus Imperial System for Diving?

[Aguablanco1]

---------- Post added October 8th, 2014 at 12:49 AM ----------



What is so difficult to comprehend about working with multiples of 1 bar/min breathing gas Surface Consumption Rate in Metric versus 14.5 psi/min in US Imperial Units??? You've got no excuse, justification or rationale if you don't even try & understand. . .

You assume that I need some excuse, rationale or justification to keep using the system that is most intuitive to me. It doesn't matter that metric is easier for some people, it is not what is easier or more intuitive for me. I think Chevy ' are easier to drive, why don't you have one? It is obvious that cotton is the superior clothing fabric, don't you agree? This whole argument is diametrically opposed to my first principle of diving. I do and use what I deem appropriate and safe. You do the same. If we both come up alive who was wrong?
We have very similar discussions in the whitewater rafting community about the "proper" gear and techniques. It is as silly there as it is here.
RichH

 

[Aquavelvet]

The correct system is the one you and your buddies or teammates have agreed to use. I tend to use metric for my own purposes, but have switched the SPG on my doubles rig to PSI, because that is what people use locally.


Sent from my iPad using Tapatalk

 

[Kevrumbo]

You assume that I need some excuse, rationale or justification to keep using the system that is most intuitive to me. It doesn't matter that metric is easier for some people, it is not what is easier or more intuitive for me. I think Chevy ' are easier to drive, why don't you have one? It is obvious that cotton is the superior clothing fabric, don't you agree? This whole argument is diametrically opposed to my first principle of diving. I do and use what I deem appropriate and safe. You do the same. If we both come up alive who was wrong?
We have very similar discussions in the whitewater rafting community about the "proper" gear and techniques. It is as silly there as it is here.
RichH

Answer the question objectively then without all that crap rhetoric above: what is so hard about understanding how to work with the Multiplicative Identity Unit of 1 bar/min* ATA in Metric???

Anything multiplied-by-one is itself . . .can you understand how much easier AND SMARTER that is to do arithmetically with regard to Gas Management Calculations, both pre-planning and on-the-fly???

 

[RJP]

No you don't, and yes it IS easier. He mentioned "weighing 100 pounds". Weight is NOT the same as mass. Weight is the force on the object. 100 pounds force is 100 pounds force regardless of displacement of the water.. you need to apply 100 "pounds force" in the opposite direction to make it "weightless". If he mentioned "mass" of the object, then we would need to know the displacement of the water to figure out the weight.

Um... no.

Time to dig out your Open Water manual, where buoyancy is covered in Chapter 1.

If displacement is not a factor in determining buoyancy please explain why THIS object - which weighs 2oz - sinks...

Yet THIS object - which weighs 22oz - floats...

Unless you're telling me that the basketball will sink if I weigh it in grams...

 

[nimoh]

Um... no.

Time to dig out your Open Water manual, where buoyancy is covered in Chapter 1.

If displacement is not a factor in determining buoyancy please explain why THIS object - which weighs 2oz - sinks...



Yet THIS object - which weighs 22oz - floats...



Unless you're telling me that the basketball will sink if I weigh it in grams...

The way that post was worded "Let's say you have an object weighing 100 pounds at 60 feet depth." could be interpreted to mean that the object is 100 lbs negative at 60 feet. It might weigh 200 lbs on the surface, but if it weighs 100 lbs at 60' of depth then its displacement doesn't matter. I think it is a bit of a reach, as I would never word it that way, and would reword it to be "Let's say you have an object that is 100 pounds negatively buoyant at 60 feet depth".

 

[RJP]

The way that post was worded "Let's say you have an object weighing 100 pounds at 60 feet depth." could be incorrectly interpreted to mean that the object is 100 lbs negative at 60 feet... It might weigh 200 lbs on the surface, but if it weighs 100 lbs at 60' of depth then its displacement doesn't matter. I think it is a bit of a reach, as I would never word it that way, and would reword it to be "Let's say you have an object that is 100 pounds negatively buoyant at 60 feet depth".

Yup - the object's weight (the downward force exerted by the Earth's gravity) does not vary based on depth or displacement. Accordingly, forum participants can only go on what was written and assume that the writer meant what they said.

Imagine if forum participants were to assume that most posters on ScubaBoard didn't know what... they were... uh... talking about. Umm, uhhhh, hmmm...

Nevermind.

 

[miked]

My take: both systems work, just use the one with which you/your buddy/group are more comfortable .

and
Gentlemen. Really? A pissing contest in the "flame free" Basic scuba forum?.......

 

[victorzamora]

My take: both systems work, just use the one with which you/your buddy/group are more comfortable .

and
Gentlemen. Really? A pissing contest in the "flame free" Basic scuba forum?.......

It was moved here, split from another thread. Most of the pissing was moved here by a mod.....so.......

 

[RJP]

Gentlemen. Really? A pissing contest in the "flame free" Basic scuba forum?.......

Do note that this thread began elsewhere and the pissing contest was well underway before the thread was moved TO the flame free zone. Perhaps the pissing will extinguish the flames?

 

[dfx]

The way that post was worded "Let's say you have an object weighing 100 pounds at 60 feet depth." could be interpreted to mean that the object is 100 lbs negative at 60 feet. It might weigh 200 lbs on the surface, but if it weighs 100 lbs at 60' of depth then its displacement doesn't matter. I think it is a bit of a reach, as I would never word it that way, and would reword it to be "Let's say you have an object that is 100 pounds negatively buoyant at 60 feet depth".

Actually I was going for a "how much air from your tank do you need at most" kind of solution, which is the obviously important part. Either way it doesn't matter, whether you take the buoyancy of the object itself into account or not, it's always much easier to work out in metric.