The vessel must adhere to IMO (International Maritime Organization) regulations. Specifically, ensure the ship is built according to IACS (International Association of Classification Societies) standards, such as ABS, BV, CCS, or LR. Essential certifications include the International Load Line Certificate, MARPOL (Prevention of Pollution) compliance, and SOLAS (Safety of Life at Sea) standards. For B2B buyers, always request the Certificate of Classification and the Builder's Certificate to verify structural integrity.