What is the observed static pressure during normal operation known as?

The observed static pressure during normal operation is referred to as normal demand pressure. This term specifically denotes the pressure measured in a fire protection system when it is under typical operating conditions, meaning that it accurately reflects the pressure available within the system during normal usage scenarios. Understanding normal demand pressure is essential for ensuring that the fire protection systems can deliver adequate water supply and pressure when needed, particularly in the event of a fire.

The other options, like dynamic pressure, would refer to the pressure encountered when fluid is in motion, and standby pressure typically indicates the pressure levels when the system is not actively supplying water. Operating pressure can be a broader term but does not specifically denote the observed measurement during normal operational conditions as clearly as normal demand pressure does. Thus, normal demand pressure is the most precise term for the observed static pressure during normal operation.