Inches of water
Inches of water (inH₂O) is a pressure unit from the Imperial system. An inch of water is defined as the pressure from a one inch column of water at 4°C (39.2°F) (which is the temperature at which water is densest).
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.