Fire caused at the stern of a dive support vessel by flaring gas from a rig

A member has reported an incident where the stern of a diving support vessel suffered fire damage caused by flaring gas from a rig vent.

The vessel was secured to the diving location via stern lines to a production structure, in order to locate and mark pipelines in the area. An open ended vent on that structure was located near the stern of the vessel and had not been identified as a potential hazard. This open-ended vent was, in fact, a component of a secondary flare system, designed to provide pressure relief to production operations by venting product in the event that the primary system failed.

With the vessel on location, the compressors on the platform shut down, the primary flare system failed and the secondary system began to vent product near to the stern of the vessel. The product ignited, causing fire damage to the vessel stern deck and equipment in the area. Personnel responded quickly to extinguish the fire on the vessel and move off location. No personal injury occurred.

The company has highlighted the following lessons learned from the incident:

• Risk assessment procedures should identify all potential hazards associated with a project, including such flare systems;
• The location, contents and function of all flare systems should be identified at the planning stage, as part of identifying the safe work area, then checked once on location;
• The isolation of all flare systems and vents in the work area should be verified prior to setting up on location;
• Planned work should be communicated with platform personnel via a safety meeting upon arrival at location.