hull insurance is taken to cover

Marine Hull Insurance offers protection to shipowners against loss of or damage to ships and related financial losses. Marine Hull insurance is a type of ocean marine insurance. This coverage protects the insured vessel or fleet against physical damage caused by a peril of the sea or other covered perils while the vessel is in transit over water.
A marine hull policy covers perils associated with maritime adventure. The important risks Covered include: Perils, Pollution Hazard, General Average and Salvage, New for Old, Bottom Treatment, Wages and Maintenance.
Marine Hull insurance policies can be written to cover a single vessel or the whole fleet of a ship owner.