Nearly all the customs administrations, together with the traditional inspection techniques of goods (phisycal inspection, documentary controls), foresee a third type of controls based on the use of scanner devices. Their objective of such tools is to make more efficient the inspection process, accelerating the release of goods, due to the fact that through this metodology more invasive exams of goods can be avoided, replaced by a "photography" of the container's content. The WCO has developed, since 2009, Guidelines for the purchase and deployment of scanner devices, suggesting, among other things, the integration of the scanner techniques within the risk analysis systems used by the members of the Organization.