Divetech99
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Is this correct ?
METRIC
turn pressure = start pressure - (bottom volume ÷ cylinder capacity)
It doesn't seem right. The lower your sac rate, the higher the turn pressure.
Example:
Start pressure = 200 bar
Depth = 30 meters
B Time = 10 minutes
RMV = 25 liters/min
ATA = 4
Bottom vol required = 1000 liters
Turn pressure = 109 bar (using above formula)
However if a diver's RMV is lower at 15 ltr/min bottom gas required is only 600 liters of air BUT Turn Pressure becomes 146 Bar???
So using the above TP formula, a diver with with a lower RMV (15 lpm) has to turn the dive sooner (at 146 bar spg reading) than someone with a 25 liters per min RMV (TP of 109 bar)?
Doesn't look right.
METRIC
turn pressure = start pressure - (bottom volume ÷ cylinder capacity)
It doesn't seem right. The lower your sac rate, the higher the turn pressure.
Example:
Start pressure = 200 bar
Depth = 30 meters
B Time = 10 minutes
RMV = 25 liters/min
ATA = 4
Bottom vol required = 1000 liters
Turn pressure = 109 bar (using above formula)
However if a diver's RMV is lower at 15 ltr/min bottom gas required is only 600 liters of air BUT Turn Pressure becomes 146 Bar???
So using the above TP formula, a diver with with a lower RMV (15 lpm) has to turn the dive sooner (at 146 bar spg reading) than someone with a 25 liters per min RMV (TP of 109 bar)?
Doesn't look right.