During "Storm Ingunn" on 31 January 2024, a large wave (green water) hit the Åsgard A facility.

The pressure from the wave exceeded the load resistance of the cabin window, and both the window and window frame were forced into the cabin.

Green water

Whole waves that wash over the deck of a vessel or facility are often referred to as “green water”. (This is in contrast to “white water”, which is sea spray or the foam at the top of a wave)

Green water can impose substantial loads (wave loading) on any objects that are hit.

Actual and potential consequences

No one was injured during the incident.

The incident caused material damage, both inside and outside the cabin, as a result of large quantities of seawater surging into the facility’s living quarters.

Had anyone been present in the cabin at the time of the incident, the window and the frame, as well as seawater, could have hit them and caused a serious injury or fatality.

Direct and underlying causes

The direct cause of the incident was that the force exerted by the green water exceeded the load resistance of the cabin window.

The investigation has identified several underlying causes. These were:

  • Location of emergency escape shaft
  • Design and execution of the window fixing
  • Lack of protection for cabin windows
  • Lack of green water model tests
  • Lack of follow-up of observations

Non-conformities and improvement points

During the investigation, we identified non-conformities concerning:

  • Inadequate assessments for green water
  • Lack of compliance with internal requirements for covering of cabin windows and inadequate use of experiential knowledge
  • Weakened load resistance of cabin windows

We also observed one factor that we have chosen to categorise as an improvement point. This concerned:

  • Wave measurements and meteorological observations.

Order

The incident on Åsgard A had the potential to cause serious injury or fatality.

Through the investigation, we have identified breaches of the regulations relating to inadequate green water assessments, lack of compliance with internal requirements for covering of cabin windows and inadequate utilisation of experiential knowledge, as well as weakened load resistance of cabin windows; cf. non-conformities 9.1, 9.2 and 9.3 in the report.

We have issued Equinor with the following order:

Pursuant to the Framework Regulations, Section 69 concerning administrative decisions, Equinor Energy AS is ordered to:

  1. Identify measures and establish a plan for implementing measures to reduce the likelihood of damage, faults and hazard and accident situations occurring as a result of green water events, cf. the Management Regulations, Section 4 on risk reduction, first paragraph, cf. the Management Regulations, Section 22 on handling of non-conformities, second and fourth paragraphs.

  2. Identify measures and establish a plan for implementing measures to ensure that experiential knowledge relating to green water from own activities is utilised in improvement work, cf. the Management Regulations, Section 23 on continuous improvement, last paragraph, cf. the Management Regulations, Section 22 on handling of non-conformities, second and fourth paragraphs.

The deadline for complying with parts 1 and 2 of the order is 28 February 2025. We are to be notified when the order has been carried out.