A clause in a Marine Hull policy excluding certain risks such as paid towage or salve work or being towed except where customary or, to a limited extent, when in need of assistance.
Insurance Encyclopedia
Navigation risks
The risks arising when a vessel is navigating or at sea as distinct from the risks arising in port or when the vessel is laid up.
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The risks incidental to a vessel navigating or at sea, as opposed to those arising while the vessel is in port or laid up.
Navigation Warranty
A warranty in a hull Policy restricting the vessel’s operational area. Breach of warranty, is normally, held covered subject to payment of additional premium.