Water pressure (diving)

[rich 36]

Something that has popped into my head
from god knows where.



would the water pressure, measured in one of these
training towers,

be somehow, innacurate, in terms of diving in the ocean,


as in below (actual)Sea level

[s2art]

Plausibly, if the concentration of salts is different to sea water.

[djfish]

Pressure = Depth * Density, I wouldn't have thought the altitude of the body of water would make much of a difference.............Is that what you were after?

[rich 36]

salt water!

gosh haden't even thought that far ahead.

no in broad terms if you swam 10M down the tower, would you still be above
real sea level if you jumped off the Sub in comparison

[tombaron]

The overall pressure takes into account barometric pressure at the surface. Because the 'surface' in the tower is above ground level, then barometric pressure will be lesser. However, the effect will be negligable.

[rich 36]

NO I wasen't thinking of a life and death
'equipment good for 51M only'

just querying

[tombaron]

If the tower is a pressure vessel then pressurising the air at the top will simulate depths greater than 51m

[rich 36]

Oh pressure-ised well that makes some sense ta

[geoff82]

Actually we use a very similar thing called the Submarine Escape Tower, which is at the Submarine training school, HMS Raleigh. Because the depth inside the tower is still commensurate with plausible escape depths and pressure is a measure of force over unit area, the pressure is indeed the same as if you were in the ocean!

[rich 36]

geoff82 said:

Actually we use a very similar thing called the Submarine Escape Tower, which is at the Submarine training school, HMS Raleigh. Because the depth inside the tower is still commensurate with plausible escape depths and pressure is a measure of force over unit area, the pressure is indeed the same as if you were in the ocean!

now in laymans terms,

is there a sliding scale of negligble difference in
'fabricated' depth created in this artificial environment,

to compare with escaping from a submarine at depth

>> Edited by rich 36 on Sunday 5th February 13:59

[geoff82]

There are 2 factors which affect the density of water and in turn affect the pressure at a given depth. These are:

Temperature, (Warm water is less dense)
Salinity, (higher salt content increases density)

The variations in both do not significantly affect density at a given depth, especially as depth increases. This is because salinity and temperature are fairly uniform all year round under a certain depth (about 1000 metres)

The actual variation caused is about 1 percent maximum at the surface and so there should be no significant difference between the pressure in the escape tower and the ocean at a given depth.

Also remember pressure equals force divided by area, so the atmospheric pressure on top of the ocean and the top of the tower is still the same, (As the increased height of the tower again only has a minute difference in air pressure at the top compared to the ocean), as well as the water pressure.

Hence, the pressure is almost exactly the same in the tower and under water at any depth.

Hopefully i've managed to explain that more clearly, but if not let me know!