4.6.1 Machinery essential for the safety of the
unit should be provided with effective means for its operation and
control.
4.6.2 Automatic starting, operational and control
systems for machinery essential for the safety of the unit should,
in general, include provisions for manually overriding the automatic
controls. Failure of any part of the automatic and remote control
system should not prevent the use of the manual override. Visual indication
should be provided to show whether or not the override has been actuated.