PSI helps ensure that production complies with the governing specification, contract, or purchase order.
A final random inspection (FRI) checks finished products, often when at least 80% of an order has been produced and export-packed.
A PSI can be performed at different stages before shipment, such as checking the total amount of goods and packing, controlling the quality or consistency of goods, checking of all documentation, as for example test reports, packaging list, or verification of compliance with standards of the destination country like ASME, CE mark and import duties.
This step takes considerable time but importers consider it to be the de facto part of the inspection process.
PSI increases burdens and costs in international trade and can be counter-productive for the country of importation and its traders.