General Design Criteria/Standards cont'd

DOE-HDBK-6004-99

effects of fires on safety-class systems, structures and components. Rupture or inadvertent operation

of fire suppression systems should not significantly impair the safety function of the electrical safety-

class systems, equipment, structures and components.

The design should also provide for protection of safety-class equipment and systems from potential

failure of non-safety-class hardware systems. Equipment, instruments and electrical systems, that

provide for the isolation should be capable of withstanding the effects of design basis natural

phenomena without failure of function and should be fail-safe in the event of power loss or failure

within electrical systems.

The design bases for these structures, systems, and components should reflect: (1) Appropriate

consideration of the most severe of the natural phenomena that have been historically reported for

the site and surrounding area, with sufficient margin for the limited accuracy, quantity, and period

of time in which the historical data have been accumulated, (2) appropriate combinations of the

effects of normal and accident conditions with the effects of the natural phenomena, and (3) the

importance of safety functions to be performed.

2. Safety-class design criteria for environmental and dynamic effects: Structures, systems, and

components of safety-class electrical systems/components should be designed to accommodate the

effects of, and be compatible with, the environmental conditions associated with the normal operation,

maintenance, testing, and postulated accidents (including loss of coolant accident, loss of flow

accident, loss of vacuum accident, plasma transients, magnet transients, loss of cryogen, tritium plant

events, and auxiliary system accidents).

Also, structures, systems, and components of safety-class should be designed appropriately to protect

against dynamic effects, including the effects of missiles, pipe whipping, and environmental conditions

associated with normal operation and the above postulated accidents.

3. Safety-class design criteria for sharing of structures, systems, and components: Structures,

systems, and components of safety-class electrical systems/components of the fusion facility should

not be shared among other facilities unless it can be shown that such sharing will not significantly

impair their ability to perform their safety functions.

4. Safety-class design criteria for inspection and testing of electric power systems: The design

should provide for periodic testing of safety-class electrical items to prevent equipment failure. The

tests and inspections should assess the parameters related to their safety functions. The testability

of safety-class on-site AC and DC power systems should be designed to meet the following guidelines

or equivalent.

AC systems and components: IEEE 308 and 338 Standards.

DC systems and components: IEEE 308 and 387 Standards.

5. Design criteria for electrical penetration assemblies (Safety-Class and Non-Safety Class) of Fusion

Facility containment: Containment electrical penetrations should be designed to be capable of

withstanding, without loss of mechanical integrity, the maximum possible fault current versus time

condition that could occur given a single random failure of circuit overload protective devices located

in circuits of the on-site safety-class AC/DC power systems. IEEE 317 Standard., Electrical