<p>An elongated sensor is longitudinally crimped to provide electrical isolation between two closely spaced wire conductors and to form around each conductor a surrounding elongated tube of porous soft material which permits the two conductors to become electrically shorted together in the presence of an electrically conductive fluid on the sensor. A connector detachably secured to one end of the sensor connects the conductors across the high impedance input of a signaling circuit to activate an indicator when the two conductors are shorted together.</p>
