Optically Monitoring Comb-Line of Escalators and Moving Walks

Method for monitoring at least part of a comb-line ( 18 ) of a comb plate ( 14 ) having a plurality of teeth ( 16 ), of a people conveyor ( 2 ) having a movable transportation band ( 4 ) and the comb plate ( 14 ) located at the transition ( 20 ) between the movable transportation band ( 4 ) and the stationary comb plate ( 14 ), wherein the method includes (a) taking a picture of the comb-line ( 18 ) with a camera ( 12 ); (b) comparing the picture with a reference picture; (c) determining the safety state of the comb-line ( 18 ) based on such comparison.