Abstract: A sensing edge for controlling movement of a door by actuation of a device upon an external force being applied to the sensing edge. The sensing edge includes an elongated, generally flexible tubular sheath which is secured to the door. The sheath includes an elongated, entirely hollow cavity with an optically reflective interior surface. A light transmitter is positioned proximate a first end of the sheath for transmitting a light beam toward a second end of the sheath. A light detector is positioned proximate the second end of the sheath for detecting the presence or absence of the light beam at the second sheath end. The light detector generates a signal for actuating the device upon detecting the absence of the light beam at the second end of the sheath.