2.2 Primary Guidance

  1. The primary guidance documents used during the assessment are the following:
  • MGN 654 (Merchant and Fishing) Safety of Navigation: Offshore Renewable Energy Installations (OREIs) – Guidance on UK Navigational Practice, Safety and Emergency Response and its annexes (MCA, 2021); and
  • Revised Guidelines for FSA for Use in the IMO Rule-Making Process (International Maritime Organization (IMO), 2018).
  1. MGN 654 highlights issues that need to be taken into consideration when assessing the impact on navigational safety and emergency response (search and rescue, salvage and towing, and counter pollution) caused by offshore renewable energy installation developments (wind, wave and tidal). It applies to proposals in United Kingdom internal waters, Territorial Sea and Exclusive Economic Zone.
  2. MGN 654 includes several annexes including the Methodology for Assessing the Marine Navigational Safety and Emergency Response Risks of Offshore Renewable Energy Installations (OREI) which the MCA require to be used as a template for preparing NRAs. The methodology is centred on risk management and requires a submission that shows that sufficient controls are, or will be, in place for the assessed risk to be judged as broadly acceptable or tolerable with mitigation (see section 3.2). In both volume 2, chapter 13 and this NRA, the base and future case levels of risk have been identified as well as the mitigation measures required to ensure the future case remains broadly acceptable, or tolerable with mitigation.

2.3 Other Guidance

  1. Other guidance documents used during the assessment include:
  • MGN 372 Amendment 1 (M+F) Safety of Navigation: Guidance to Mariners Operating in the Vicinity of UK Offshore Renewable Energy Installations (OREIs) (MCA, 2022);
  • International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA) Recommendation RO138 (O-139) The Marking of Man-Made Offshore Structures (IALA, 2021a);
  • IALA Guidance G1162 The Marking of Offshore Man-Made Structures (IALA, 2021b);
  • The Royal Yachting Association’s (RYA) Position on Offshore Renewable Energy Developments: Paper 1 (of 4) – Wind Energy (RYA, 2019); and
  • Regulatory Expectations on Moorings for Floating Wind and Marine Devices – (MCA and Health and Safety Executive (HSE), 2017).

2.4 Lessons Learnt

  1. There is considerable benefit in the sharing of lessons learnt within the offshore industry. The NRA, and in particular the risk assessment undertaken in volume 2, chapter 13, includes general consideration for lessons learnt and expert opinion from previous offshore wind farm developments and other sea users, capitalising upon the UK’s position as a leading generator of offshore wind power.

3 Navigational Risk Assessment Methodology

3.1 Formal Safety Assessment Methodology

  1. A shipping and navigation user can only be exposed to a risk caused by a hazard if there is a pathway through which a risk can be transmitted between the source activity and the user. In cases where a user is exposed to a risk, the overall significance of risk to the user is determined. This process incorporates a degree of subjectivity given it relies on qualitative definition of frequency and occurrence. The assessments presented herein for shipping and navigation users have considered the following criteria:
  • baseline data and assessment;
  • expert opinion;
  • stakeholder consultation comments including output of the Hazard Workshop for the Array;
  • time and/or distance of any deviation;
  • number of transits of specific vessels and/or vessel types; and
  • lessons learnt from existing offshore developments.
  1. It is noted that, with regards to commercial fishing vessels, the methodology and assessment has been applied to hazards considering commercial fishing vessels in transit. A separate methodology and assessment for commercial fishing vessels have been applied in volume 2, chapter 12 to consider hazards on commercial fishing vessels including safety risks which are directly related to commercial fishing activity (rather than commercial fishing vessels in transit) and risks of a commercial nature.