Challenges in a Multidisciplinary Approach for Explosion Design for Floating Facilities

Abstract

environment compared with onshore liquefied-natural-gas plants or other floating offshore installations. As a consequence, the explosion risk is expected to be higher than that for some other offshore floating facilities. Because of the general evolution of design practices, alternative approaches such as performance with risk-based design can be used. The performance-based approach relies on the explicit definition of the safety objectives and functional requirements (e.g., performance standards). The design process focuses on the objectives, not the means to reach them. Because it is based on the definition of realistic explosion scenarios, which could be deterministic (e.g., scenario-based approach) or probabilistic (risk-based), the design process requires more resources (skills, computational tools) that allow the contractor to demonstrate the compliance of the solution with the safety objectives. This could be a challenge because any design solution is specific to the installation and requires the acceptance of the operator, the local authority, and the classification society. All participants should ensure that they understand, agree with, and are aware of the limitation of the proposed design solution, to avoid further rework. During the entire engineering process, different barriers are investigated to reduce the risk of potential losses (people, assets) from the potential explosion hazards to as low as reasonably practicable, as shown in Fig. 1. Even if inherent safety is a key driver during the design phase of the facility, additional risk-reduction measures that combine prevention, detection, control, and mitigation are usually implemented. Emergency response (e.g., rescue of people) remains the ultimate option. Many of these barriers should be designed or verified against major-accident events to fulfill their function during and after the initial explosion event. This paper focuses on the design process and associated challenges of such barriers because they require an integrated multidisciplinary approach that combines the expertise of safety, structural, and equipment engineers.