Recently installed a new sub panel for the fueling islands that is controlled by a shunt trip breaker in the main panel. The shunt trip breaker is tripped when the emergency shut off switch is tripped. The sub panel contains 4 switch neutral breakers for the gas dispensers. The shunt trip breaker when tripped kills the power to the subpanel but does nothing to the neutrals. Is it required that the neutrals be disconnected from the main panel also?