Power

DOE-HDBK-6004-99

requirements. Test features of the safety system I&C should be able to detect failures of the system

that could degrade or prevent a safety function from occurring in the presence of a single failure.

The I&C system should include maintainability considerations in the design process. These

considerations should include ease of replacement of components, modules, or subsystems, the access

availability of the equipment with consideration for personnel hazard conditions (radiation, magnetic

fields, temperature, proximity to steam piping or other stored energy conditions, etc.), and the

provision for sufficient bypass or disable capability and test point access to allow for the valid

performance of necessary and adequate testing.

Power

The I&C power system design should provide for the necessary redundant power sources to ensure

that the system will be capable of performing its required function under all normal and postulated

accident scenarios. Power sources that should be considered for the I&C system include

uninterruptible power sources, critical instrument busses capable of being powered from diesel

generator back up power, and battery back up systems.

Control Room Design

The design of the control room should be implemented in accordance with IEC 964 standard

guidelines, with the appropriate modifications for fusion versus fission technologies and hazards. The

underlying principles of the man/machine interface and functional analysis presented in IEC 964 are

appropriate to the design of fusion control facilities.

Adequate radiation and environmental protection should be provided to permit access and occupancy

of the control room under accident conditions where the operator monitoring, mitigative or response

actions are required during or following an accident.

Equipment at locations outside the control room should be provided to achieve and/or maintain the

facility systems in a safe or shutdown condition in the absence of the control functions designated for

that purpose.

Safety Actuation

Safety function actuation should be sealed in, so that the safety function actuation is maintained even

if the logic that initiates the actuation is lost.

Monitoring

Monitoring of after-heat removal after-heat removal (and normal operating heat removal) should

include sufficient information processing and displays to present the heat balance and energy transport

and verify parameters are within the expected ranges. Higher order logical processing and display

may be required to present operators with an integrated picture of the fusion heat removal system.

The input sensors, algorithms, software and hardware required for this safety-significant activity

should meet appropriate reliability standards.

The inherent robustness of the facility confinement systems should be analyzed (and demonstrated)

to show survivability during PIE with the worst case performance of the I&C System. The design