3.5.8.2

Are auditory and visual alert signals

  1. unambiguous and
  2. perceivable from all relevant workplaces in the control room under all operating conditions?

The purpose of auditory and visual alert signals is to attract the operators' attention to a deviation. The use of flashing (or blinking) should be limited. E.g., in alarm messages, only a small symbol should be flashing. Text should never flash. Instead of flashing, other effects could be used that are less disturbing to the eye (i.e. raised face / 3D-effects that highlight new alarms). Operators should be able to easily distinguish between system alarms, process alarms and events.

Note to point B - in some cases there could be just one operator alone in the CC, can he perceive all alarms?

Comments/Recommendations

NUREG0700, point 4.2.3-1, p. 272., NUREG0700, point 4.6-1, p. 299YA-711, point 35, 36, 39, p. 19-20.
DC: Applicable to the DC