FPSO units are not considered offshore structures as they are not permanently fixed to the seabed.

Steel is the most commonly used material for offshore structures due to its strength, durability, and ease of fabrication.

Structural integrity is the primary design consideration for offshore structures as they are subjected to harsh environmental conditions and dynamic loads.

Cathodic protection is a technique used to prevent corrosion of offshore structures by applying a negative electrical potential to the structure.

Ultrasonic testing is a non-destructive testing method used to detect flaws and defects in underwater members of offshore structures.

Risers are used to transport produced oil and gas from the seabed to the surface platform or onshore facilities.

Tension leg platforms are designed for deepwater applications as they are held in place by vertical tension tethers rather than resting on the seabed.

Sacrificial anodes are used to protect offshore structures from corrosion by corroding themselves instead of the structure.

Steel is the most commonly used material for underwater pipelines due to its strength, durability, and ease of installation.

Mooring systems are used to keep offshore structures in place by anchoring them to the seabed.

Jack-up platforms are commonly used for drilling exploratory wells as they can be easily moved from one location to another.

Blowout preventers are used to prevent uncontrolled release of hydrocarbons from a well in the event of a blowout.

Floating storage and offloading units are used for the storage of produced oil and gas before it is transported to shore.

Subsea manifolds are used to collect and distribute fluids from multiple wells to a central processing facility.

Accommodation platforms are specifically designed to provide living quarters and facilities for personnel working on offshore oil and gas platforms.