3m water tower.
MPa is approximately equal to 10kgf/cm2, 1kgf/cm2 is approximately equal to 1 atmosphere, which is the normal ambient air pressure in which we live. 1 atmosphere is approximately equal to 10 meters of water column, and 1MPa is approximately equal to 100 meters of water column. This 0.03MPa is approximately equal to 3 meters of water column.
MPa is a unit of pressure, the full name is MPascal.