Navigation and Collision Risk

Offshore vessels, including supply boats, tankers, and drilling rigs, face navigation hazards. Collision between vessels or with offshore structures can result in damage, spills, and personnel injuries.

Navigation and collision risks are significant concerns in offshore operations, particularly in areas with high maritime time traffic and complex infrastructure such as oil and gas fields.

Past accidents

Exxon Valdez Oil Spill (1989): The Exxon Valdez, an oil tanker, ran aground in Prince William Sound, Alaska, resulting in one of the most infamous oil spills in history. The accident occurred due to navigational errors, and the tanker stuck Bligh Reef, causing a massive release of crude oil into the environment.

Sanchi Oil Tanker Collision (2018): The Sanchi, an Iranian oil tanker, collided with a Chinese bulk freighter off the coast of Shanghai. The collision results in a significant oil spill and the sinking of the Sanchi. Navigation issues and communication failures were cited as contributing factors.

Cause of Navigation Risk and Collision Risk

Here are some common causes of Navigation and Collision Risk .

• High Traffic Area; especially those near major shipping lanes or in regions with extensive oil and gas activity.
• Dynamic Weather Condition, including high wind, rough sea, reduced visibility.
• Platform-to-Platform Transfer since the transfers of personnel and supplies between offshore platform, vessels, and support boats can pose collision risk.
• Navigation challenges since navigation in offshore area may involve navigation around fixed structures, seabed, underwater pipelines, and etc. Adequate mapping and communication between vessel operation and offshore installation are essential.
• Use of Dynamic Positioning (DP) System; DP system is required to maintain a stable position. However, reliance on DP system can create challenges if there are malfunctions or if operators do not have adequate training in DP operation.
• Ice and Arctic Navigation; In specific Arctic Regions, navigation risks are compounded by the presence of ice. Icebergs and sea ice pose collision risks

Design Codes and Standards

Reducing navigation and collision risks in offshore operations involves adhering to industry-specific design codes and standards. Here are some relevant design codes and standards;

• International Maritime Organization (IMO) regulation which includes COLREGs (International Regulations for Preventing Collision at Sea): These rules establish the conduct of vessels to prevent collision and are crucial for safe navigation. The few examples such as
  • Rule-5: Lookout
  • Rule-6: Safe Speed
  • Rule-7: Risk of Collision – “Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if the risk of collision exits”
  • Rule-8: Action to avoid collision – “Action taken to avoid collision with another vessel shall be such as to result in passing at a safe distance“
  • Rule-10: Traffic Separation Schemes – “Proceed in the appropriate traffic lane in the general direction of traffic flow for that lane”
  • Rule-12: Sailing Vessel – “Windward vessels shall keep clear of leeward vessel, and overtaking vessels shall keep clear of vessels being overtaken”
  • Rule-14: Head-on situation” When two power-driven vessels are meeting head-on or nearly head-on, each shall alter her course to port (left)”

• SOLAS (International Convention for the Safety of Life at Sea) provides a comprehensive wide range of aspects related to ship safety, including navigation and collision prevention such as
  • Chapter I – General provisions – Part B – Surveys and certificates – Regulation 7 – Surveys of passenger ships
  • Chapter I – General provisions – Part B – Surveys and certificates – Regulation 8 – Surveys of life-saving appliances and other equipment of cargo ships
  • Chapter V – Safety of Navigation

• IEC 61892 provides a series of standards covering electrical installations in mobile and fixed units used in the offshore industry. Compliance with these standards helps ensure the safety and reliability of electrical systems.