Abstract: A walkway or escalator system for the conveyance of standing passenagers comprises a termination plate associated with the travelling surface and a detector device responsive to the sensing of material ingested between the leading edge of the termination plate and travelling surface so as to shut-off the system in the event that ingestion is detected. Alternatively or in addition the system comprises means for detecting a blockage at the discharge end of the travelling surface as may arise of luggage accumulates at that point or if a passenger falls or is trapped. The detector means operates by sensing the presence of relatively stationary objects or passengers at the discharge end and shuts-off the system if blockage is detected.