What unit is typically used to refer to water pressure?

Water pressure is commonly measured in pounds per square inch (psi) because it quantifies the force exerted by water within a given area. Psi is a widely accepted unit in many engineering and technical fields, especially in hydraulics and water supply systems. This measurement allows for an understanding of how much pressure is exerted by water in pipes, tanks, and other systems, which is critical for proper design and safety considerations.

In contrast, pounds per gallon refers to weight, not pressure, making it unsuitable for expressing pressure levels. Kilograms per square meter is another metric unit used to express pressure, but it is less common in practical applications involving water systems in places where psi is the standard. Liters per second measures flow rate, which is not a direct measurement of pressure but of volume flow, highlighting the difference in the types of units used for different purposes in water system dynamics.