Boiler Superheater tubes precleaning & passivation?

A power plant that is going to have a new boiler asking if there is any procedure to clean/preserve/passivate the super-heater tube before it is put into operation.

Since the super-heater tube is not meant to be submerged under water, I am not sure if there is any procedure that can be done to clean/preserve/passivate the super-heater tube.

Thanks in advance for your input.