Scope
The facility experienced repeated ambiguity at a shared waiting point. People approaching from two directions could not reliably determine which sequence they had entered. A call control was available, but its placement sat outside the ordinary access envelope.
Observed conditions
MQT recorded approach, recognition, entry and dwell conditions. MPS reviewed the call control’s intended and ordinary position. Meridian Ambient recorded background conditions affecting recognition. Button & Interface reviewed response certainty after the control was relocated.
Method and result
The access envelope was redrawn using PCP-87-24. The approach path was retained, but the sequence recognition point was moved before the merge. The control was returned to a position visible from the ordinary approach without occupying the waiting envelope. Follow-up review recorded a stable ordinary position and no new return condition.