Proceedings of the Eighth International Conference on Probabilistic Safety Assessment & Management (PSAM)
232 Integrated Safety Assessment of Small Container Ships (PSAM-0234)
Download citation file:
- Ris (Zotero)
- Reference Manager
On 15 August 2000, without prior indication, disaster struck onboard the container ship “Dongedijk”. The ship capsized shortly after leaving Port Said, Egypt, on a flat calm sea. Fortunately, no lives were lost and the environment was not compromised. The Dutch Shipping Council investigated the accident and concluded that the vessel did not comply with all statutory stability regulations. Disciplinary action has been taken on both the Captain and the First Navigating Officer.
The accident initiated an intense discussion on the safety onboard small container ships, as it was widely felt that there was more to it. The Dutch Ministry of Transportation has assigned the Maritime Knowledge Centre to further investigate the safety of small container vessels with respect to stability.
The research was conducted along four separate paths: a general quantitative risk assessment, both a qualitative and a quantitative analysis of the working environment and a quantitative analysis of the technical aspects of stability.
The philosophy underlying the general quantitative risk assessment was in accordance with the guidelines for Formal Safety Assessment of the International Maritime Organization (IMO). The assessment was performed by a broad selection of experts from the shipping sector.
Both the quantitative and the qualitative analysis of the working environment was based on TRIPOD, an investigation method which classes latent failures in eleven Basic Risk Factors, such as “Maintenance management”, “Communication” and “Design”. The quantitative analysis was based on questionnaires issued under Captains and Navigating Officers, the qualitative analysis was based on interviews of the same target group.
The quantitative analysis of the intact stability of container vessels was performed through a combination of two simulation tools. The non-linear time-domain simulation program FREDYN, originally designed for naval vessels, has been validated as applicable to container vessels by model tests. FREDYN in conjunction with GULLIVER allows computation of statistical distributions of ship behavior in waves for a specific sea area and route, taking into account the variability of Captain's decisions.
In this paper, the authors give insight into the above mentioned methods, the results and share their experiences obtained during the safety assessment of container vessels.