A Novel Solution for Retrospective Enhancement of Passenger Vessel Damage Stability

Ship flooding and inadequate damage stability remains the greatest risk to life in the maritime industry today. To address this problem, increasingly stringent damage stability regulations have been introduced at the international level, most recently SOLAS 2020. However, these apply only to new vessels, leaving the majority of the global fleet under older, more lenient regulations. In fact, the effect of these regulatory changes won't be fully realized for 30-40 years, when older ships are phased out, and that is a long time to wait. The challenge lies in the difficulty and cost of retrofitting older ships to meet modern standards. Adding to the problem is the tendency for the stability of vessels to deteriorate over time, meaning the situation is liable only to get worse. At the heart of the issue has been an overreliance on subdivision as the primary method of controlling flooding, which is exceedingly hard to retrofit in older ships and has diminishing returns with increased application. This highlights the need to seek alternative means of improving damage stability for both new and existing vessels. The research presented in this paper proposes a novel solution to this problem, namely the use of high-expansion polyurethane foam as a means of reducing vessel permeability and enhancing survivability. The system is easy to apply, making it suitable for both new and, more importantly, older ships. The paper provides an overview of the development process to date and presents a methodology for implementing the solution on ships, culminating with promising results from a recent impact assessment conducted on an existing RoPax vessel