12.1.1.7-6 Dedicated Crews

When mirror image control rooms exist, operational crews should be committed to one or the other unit and should not be allowed to alternate between the two mirrored units.

Additional Information:
This includes crews staffing a single center-desk station. Some control rooms are designed with the control boards of two units laid out symmetrically, side-by-side, so that one is a complete or nearly complete reversal of the other. Operators who work both units have to deal with two opposite patterns of controls and displays, and must reorient their expectations completely when they switch from unit to unit. This requirement violates the principle of positive transfer of training and is highly unfavorable for task performance reliability. The potential for confusion is greater when the reversal is incomplete (e.g., control boards mirror imaged, but annunciator panels arranged identically in both units).