A 'centimeter (centimetre) of water' or 'cm H
2O' is a less commonly used unit of
pressure. It is used to measure the
central venous pressure, the
intracranial pressure while sampling
cerebrospinal fluid, as well as determining pressures during
mechanical ventilation or in
water supply networks (then usually in
metres water column). It is also a common unit of pressure in the speech sciences.
It is defined as the pressure exerted by a column of
water of 1
cm in
height at 4
°C (temperature of maximum density) at the standard acceleration of gravity.
This unit is commonly used to specify the pressure to which a
CPAP machine is set after a
polysomnogram.
:1 cmH
2O = 98.0638
pascals
To convert this measure to other units, the following conversion is used:
:1
mmHg = 1.36 cmH
2O = 0.133
kPa = 0.0193
psi = 1.3332
mbar
External links
★
Pressure conversion calculator at
Cornell University website