Disclosed is a system including a conveyer, a sensor operationally directed to engage the conveyer, a controller for controlling the conveyer and the sensor, the controller renders a plurality of determinations including: a first determination that the conveyer is in an operational state, a second determination that first sensed data dynamically obtained from the sensor is indicative of a first passenger on the conveyer, a third determination to model shape of the first passenger, while the first passenger is on the conveyer, with a first nodal model, a fourth determination to track displacement differentials for the first nodal model, a fifth determination to identify from the differentials an occurrence of an alert condition with the first passenger, at an occurrence of an alert condition, a sixth determination to stop the conveyer, and the controller transmits first instructions to the conveyer to effect the sixth determination.