Few metal-based surfaces are able to endure the relentless corrosive forces that occur around Marine environments. For this reason, anti-corrosive magnetic alloys or magnets with protective coatings are often employed to resist these conditions.

Businesses or recreational activities that encounter marine environments include shipyards, fishing operations, public marinas, cruise ships and sightseeing vessels.

Samarium Cobalt (SmCo) magnets are manufactured from highly corrosion-resistant Rare Earth alloy and are ideal for harsh aquatic conditions. They are also able to tolerate heat affected applications (up to 300°C).

Similarly magnets with protective coatings may also be suitable for marine environments. Coatings of Teflon, Plastic or Epoxy protect the magnet from the harsh conditions that marine environments present. However these protective coatings would not be suitable for application that required the magnet to be submerged for prolonged periods in water.

Shipwrights that need to repair or modify steel hulled vessels find countless uses for corrosion resistant magnets and often find them to be an excellent holding or clamping tool as they perform their work. International shipping companies with vessels that move thousands of steel containers around the world also find magnets invaluable. Booms that float on the ocean surface and contain oil spills from ruptured tankers are often attached magnetically, as are the access ladders that harbour pilots use to board container ships as they approach a port or prepare to dock at a terminal.

Some underwater salvage operators use sealed magnetic retrieval devices to drag the seabed or waterways for submerged metallic materials that need to be removed to prevent contamination or retrieved for their monetary value.