A method of passivating a metal surface in a primary system of a new nuclear power plant having a nuclear core, a pressurizer and coolant water flowing through the primary system, prior to the initial loading of nuclear fuel into the reactor core and prior to initiating normal operation of the new nuclear power plant, the method comprising: prior to initiating pre-core hot functional testing, filling the primary system with demineralized water and adding an oxygen scavenger to the primary system and pressurizer at low temperatures to scavenge oxygen in the coolant water; achieving an alkaline-reducing phase, comprising: heating the primary system to a simulated normal operating temperature prior to an initial loading of fuel in the nuclear core; initiating an addition of zinc to the coolant water at a temperature greater than or equal to 177°C (350° F) prior to reaching the simulated normal operating temperature; achieving a target zinc concentration in the coolant water from greater than 40 to 300 ppb at the simulated normal operating temperature; conducting hot functional testing in the primary system at the target zinc concentration and the simulated normal operating temperature; allowing the zinc to contact the metal surface in the primary system; and forming an initial zinc-containing oxide film on the metal surface initiating an acid-reducing phase to simulate a plant shutdown chemistry condition, comprising: adding boric acid to the coolant water; and initiating an acid-oxidizing phase, comprising: reducing temperature and removing hydrogen from the coolant water. prior to initiating pre-core hot functional testing, filling the primary system with demineralized water and adding an oxygen scavenger to the primary system and pressurizer at low temperatures to scavenge oxygen in the coolant water; achieving an alkaline-reducing phase, comprising: heating the primary system to a simulated normal operating temperature prior to an initial loading of fuel in the nuclear core; initiating an addition of zinc to the coolant water at a temperature greater than or equal to 177°C (350° F) prior to reaching the simulated normal operating temperature; achieving a target zinc concentration in the coolant water from greater than 40 to 300 ppb at the simulated normal operating temperature; conducting hot functional testing in the primary system at the target zinc concentration and the simulated normal operating temperature; heating the primary system to a simulated normal operating temperature prior to an initial loading of fuel in the nuclear core; initiating an addition of zinc to the coolant water at a temperature greater than or equal to 177°C (350° F) prior to reaching the simulated normal operating temperature; achieving a target zinc concentration in the coolant water from greater than 40 to 300 ppb at the simulated normal operating temperature; conducting hot functional testing in the primary system at the target zinc concentration and the simulated normal operating temperature; allowing the zinc to contact the metal surface in the primary system; and forming an initial zinc-containing oxide film on the metal surface initiating an acid-reducing phase to simulate a plant shutdown chemistry condition, comprising: adding boric acid to the coolant water; and initiating an acid-oxidizing phase, comprising: reducing temperature and removing hydrogen from the coolant water.