Standards drive a lot of the differences between onshore and offshore installations, but some things are simply down to preferences, or established industry practices. Some of the biggest noticeable differences with offshore installations are:
1. Cables – braided armour is more common, low-smoke, zero-halogen (LSZH) cables mandatory
2. Cable transits – Multi Cable Transits (MCTs) will be used for all penetrations through walls, rather than the block and cement work often used onshore
Familiarity with terminating braided armour cables and working with MCTs would be a big advantage for anyone trying to get into the offshore industry.