cmH₂O

centimeter of water column

Pressureexact by definition

The centimetre of water column is exactly 98.0665 pascals on the conventional basis. It is the unit of respiratory medicine: ventilator pressures, CPAP settings and lung compliance are all in cmH₂O, and a normal breath moves about 5 to 10 of them.

1 cmH₂O 0.0980665 kPa