A sensor which is installed in a waste tank to determine when the tank is full includes a shroud having a body with a curved surface and a leading edge which is mounted flushly to the inner surface of the tank wall and a trailing edge which is spaced apart from the sensor face. As waste material is swirled...http://www.google.com/patents/US5105974?utm_source=gb-gplus-sharePatent US5105974 - Liquid level sensor cover for waste holding tank
