Abstract: One aspect of the invention provides a detection system for determining whether an object is present at a predeterminable location, the system comprising a sensor tool including an air outlet at a forward surface thereof from which an air flow is in use delivered; an air catch sensor pneumatically connected to the air outlet of the sensor tool and being operative to detect a change in pressure of the air flow as delivered from the air outlet indicative of the air outlet being moved proximate a surface of an object; a positioning mechanism to which the sensor tool is attached; and a control unit for controlling the positioning mechanism to advance the sensor tool such that the air outlet of the sensor tool is advanced through at least one detection point to sense for a surface threat and determine whether an object is present at a predeterminable location.