1.Depths in the vicinity of pipelines may be less than charted as not all pipelines are buried.
When anchoring or trawling in the vicinity of a pipeline mariners should bear in mind the danger of pipeline damage which may cause fire or loss of a vessel's buoyancy. In any case of pipeline damage mariners risk prosecution.

2.In the areas of oil and gas fields drilling rigs, platforms, mooring anchors for tankers and storage tankers exist. Surface structures as a rule carry Mo(U)W lights, aero obstruction lights and sound signals. It is prohibited without special permission to approach the stated structures and other objects within less than 500m and impede free maneuvering of tankers