What is the recommended minimum water pressure from a hydrant?

The recommended minimum water pressure from a hydrant is set at 20 psi (pounds per square inch) because this level of pressure is generally considered adequate for most firefighting activities. It allows for a sufficient flow of water to effectively suppress fires, ensuring that firefighters can operate efficiently and safely.

This pressure level ensures that the water can reach the required height to combat various types of structures, while also allowing for the necessary volume to be delivered to the firefighting hoses. Having a pressure lower than 20 psi might not provide the necessary force for effective firefighting tactics, particularly in urban or densely populated areas where high flow rates are often essential.

The choice of 20 psi is based on practical firefighting scenarios, where balancing pressure with adequate water flow is crucial for effective firefighting operations.