On Site Post Clearance Audit enables premises verification of importer/exporter self assessments and mandates document access. On Site Post Clearance Audit (OSPCA) enables premises based periodic verification of importer/exporter self assessments, obliges timely provision of all import/export documents including electronic records, authorises auditors to verify declarations and take samples, and prescribes penalties for non compliance; initially applied to Accredited Client Programme importers with phased expansion and coordinated audits to avoid duplication with Central Excise and Service Tax checks.