What type and size of piping should sensing lines for fire pumps consist of?

Sensing lines for fire pumps are critical components, designed to detect water pressure changes that can signal the need for the pump to start or stop. The correct choice specifies brass piping of ½ inch in size, which is appropriate for this application due to brass's corrosion resistance and mechanical strength.

Brass is an excellent choice because it withstands the environment in which fire protection systems operate, including exposure to various chemicals and moisture. The ½ inch size allows for adequate flow and pressure sensing without introducing too much restriction, ensuring that the system operates efficiently and reliably.

In contrast, plastic may not offer the necessary durability and chemical resistance required in fire protection applications. Copper piping, while durable, may not be standard for sensing lines due to cost and potential issues with thermal expansion. Steel, particularly at 1 inch, could be more cumbersome and heavy than needed for a sensing line, which could complicate installation and maintenance. Thus, brass of appropriate size ensures optimal performance of the sensing line in fire pump applications.