Marine Cargo Hold | Oil Tank Vertical Ladder This vertical ladder is used in cargo hold or oil tank of ships. It has a reliable structure and good strength. Approved by the CB*3218-84 standard, it accords with the requirements of ISO3797-1976. Certificates like ABS, CCS, BV, DNV, LR, GL, KR, and NK are offered according to customers’ requirement. Besides, we can customize this vertical ladder to meet the clients’ demand.