It is a growing trend that fish farms are moved out of sheltered, near-shore areas and moved to locations further offshore. There are several advantages applying this solution, better fish welfare, less conflicts with interests in the ocean space as well as possibility to scale up output volume without compromising environmental sustainability are some of them. We need to be sure that facilities for exposed aquaculture can handle harsh environment and still contain the fish safely.
The main areas of concern when it comes to ensuring safe and reliable offshore fish farming units may be categories into: Asset integrity, personnel safety, fish welfare and prevention of fish escape.
Asset integrity includes structural strength, stability, mooring, technical arrangement, and solutions on board together with reliability of essential equipment installed.
Personnel safety is mainly addressing arrangement for emergency escape and fire safety. This included lifesaving appliances, launching equipment and similar as well as fire detection and -extinguishing. It is common to apply well know maritime codes as acceptance criteria for personnel safety. SOLAS is a good example with local flag- or shelf states interpretation of these requirements embedded in this maritime code.
Fish welfare and requirements related to this varies depending on local authorities. It is essential to verify the reliability of technology utilized to monitor environment of the fish. Instrumentation indicating oxygen level, temperature, salinity, turbidity is subject for special attention.
Fish control or prevention of escape is the main function of a fish farming unit. Structural integrity of net system and ropes together with capability of fish transfer systems are crucial items in fish control. Flexible net systems utilized in rigid high volume steel fish farming installation has proven to be exposed to fatigue and need to be attended to in particular. Wear and tear of net due to cleaning and handling is also a concern. Several of reported incidents related to fish escape happens while handling of fish – for example crowding due to de-licing or transfer. Equipment contributing to these operations needs to be specially attended to.
The four different items are considered equally important for safe and sustainable fish farming offshore. These items are also closely interconnected where integrity of on may support several others.
There is a significant potential to utilize competence from offshore and maritime to help operators of exposed fish farming units to identify operational risks by applying technical rules and requirements from classification.
Combining the well-known classification concept from maritime industry with balanced aquaculture-based requirements provides a robust and cost-efficient solutions to reducing risk in operation of offshore fish farming installations.