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).
bar
Bar is a unit of pressure used in various science and engineering. The bar is a metric unit of pressure defined as 100,000 pascals. Although it is not an SI unit it is widely used due to its convenient size for many applications.