To provide an apparatus for confirming generation of a debris flow which has no danger of being broken with an indirect stroke and can facilitate evacuation by arranging cables for detection also to points, where generation of far debris flow is estimated.
In this apparatus for confirming that the debris flow 21 has taken place at a predetermined point, optical fiber cable 3 for detection, each of which has one end connected to a light generator 1 and the other end connected to a light receiver 4 are arranged to the points, where the generation of the debris flow 21 is estimated. Generation of the debris flow 21 is confirmed by detecting that the optical fiber cable 3 is cut by the debris flow 21, and the light receiver 4 becomes incapable of to receiving light.
SAITO HIROYUKI
IGARASHI TOSHIYUKI
OKAWA SHIGERU