Description: the maximum  head of a pump that can deliver it during operation; Name: Greatest head allowed while operation
Description: Maximum permissible head at which the pump can be continuously operated without suffering damage; Name: Maximum allowable head
Description: NPSH-value required for a drop of 3 % in the total head of the first stage of the pump as a standard basis for use in performance curves; Name: Net positive suction head required for a drop of 3 %