I was reading Wikipedia's article on Pressure and came across this (bold is mine):
[5] is from the US Navy Diving Manual:
3. In the metric system, 10 MSW is defined as 1 BAR. Note that pressure conversion from MSW to FSW is different than length conversion; i.e., 10 MSW = 32.6336 FSW and 10 M = 32.8083 feet.
Is it true that dive computers are calibrated to this standard rather than an actual 10 Meters under seawater? Same question for computers set to Feet of Seawater.
I know that when precision pressure gauges for saturation diving systems were ordered in feet or meters of seawater based on the actual linear distance.
Underwater divers use the metre sea water (msw or MSW) and foot sea water (fsw or FSW) units of pressure, and these are the standard units for pressure gauges used to measure pressure exposure in diving chambers and personal decompression computers. A msw is defined as 0.1 bar (= 100000 Pa = 10000 Pa), is not the same as a linear metre of depth. 33.066 fsw = 1 atm[4] (1 atm = 101325 Pa / 33.066 = 3064.326 Pa). Note that the pressure conversion from msw to fsw is different from the length conversion: 10 msw = 32.6336 fsw, while 10 m = 32.8083 ft.[5]
[5] is from the US Navy Diving Manual:
3. In the metric system, 10 MSW is defined as 1 BAR. Note that pressure conversion from MSW to FSW is different than length conversion; i.e., 10 MSW = 32.6336 FSW and 10 M = 32.8083 feet.
Is it true that dive computers are calibrated to this standard rather than an actual 10 Meters under seawater? Same question for computers set to Feet of Seawater.
I know that when precision pressure gauges for saturation diving systems were ordered in feet or meters of seawater based on the actual linear distance.
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