Pascals
Pascals (Pa) are the SI units of pressure named after the French mathematician Blaise Pascal. It is defined as one newton per square meter (N/m²). Since the pascal is a relatively small unit, kilopascals (kPa), megapascals (MPa), and gigapascals (GPa) are often used for practical applications.
mm of water
The millimeter of water (mmH₂O) is a unit of pressure exerted by a 1 millimeter column of water at 4 degrees Celsius under standard gravity.