Symposium Safe Shipping on the Baltic Sea
Gdańsk 2011
Jan Jankowski
Polski Rejestr Statków S.A., Gdańsk
Email: j.jankowski@prs.pl
Implementing the Risk Approach to Develop Minimum but Sufficient Safety Standards
The trend to optimize fleets has led to new ship types adjusted to the diversity of carried cargo and loading and unloading means. New improved materials have been introduced in building ships. Bigger and faster ships, new loading technologies, improved propulsion systems and computerised deck control systems revolutionised shipping. However, these innovations were not followed by appropriately developed safety regulations.
Following a series of catastrophes, classification societies and International Maritime Organisation (IMO) developed new requirements, often retroactive in nature, which in case of ferries and bulk carriers required rebuilding/conversion of ships in operation – in effect creating a maze of regulations, which few manage to embrace. At the same time the number of controlling and auditing bodies has proliferated complicating operators’ life and frequently resulting in an adverse attitude to safety considerations.
Casualty statistics show that ”during a period of 25 years between 1982 and 2007, there were 419 bulk carriers lost, along with nearly 2000 lives'” [1]. The next few years showed a falling trend in bulk carrier casualties, however these figures leaped in 2009 [2],[3]. INTERCARGO statistics indicate that about 30% of bulk carrier total losses were caused by failure of ship structure or her equipment [4].
As early as in 1989, following the catastrophe of the tanker ''Exxon Valdez'' and heavy pollution of Alaska's coast, the US Senate resolved that tankers entering American waters must have double shell plating. This requirement was later introduced to MARPOL Convention to provide a second line of defence against polluting the environment.
In 1999, the tanker ''Erika'' broke in half and foundered along the French coast. The incident resulted from the bad technical condition of the ship hull. It caused an ecological catastrophe in the region. Similar consequences met the coast of Spain following the catastrophe of the tanker ''Prestige''.
After the disaster, the European Union issued the so-called ''Erika packages'' to improve the safety of European waters. The ''Prestige'' case induced International Maritime Organisation (IMO) to develop, for the first time, structural ship safety standards, starting with requirements for bulk carrier and tanker hull structure (so called Goal-Based Standards) and the International Association of Classification Societies (IACS) developed ''Common Structural Rules for Tankers''. Up to date the safety assurance of ship structures remains the domain of classification societies.
1994 witnessed the sinking of the passenger car ferry ''Estonia'' on route from Tallinn to Stockholm with loss of 852 lives [5]. In reaction to this catastrophe:
- IACS enhanced requirements on impact wave loads acting on the bow and formulated new requirements for the second line of defence against water ingress as well as other requirements improving ferry safety, e.g. monitoring bow visors to detect potential tightness failure;
- Swedish government organised a conference, in result of which some states, not only those of the Baltic region, signed the so-called Stockholm Agreement, referring to safety of ferries in damage condition [6].
Recent statistical data show that general cargo ships lead in the number of foundered vessels. The general cargo fleet is ageing and its replacement will follow tanker and bulk carriers replacement trend. In terms of life loss, however, small vessels, particularly fishing vessels are most vulnerable. They are often incapable of surviving extreme weather conditions in which they operate.
The biggest catastrophes in recent decades resulted in loss of life and environmental disasters. The reasons of the catastrophes were often technically related. A major problem in enhancing ship safety is the time lag between shipping industry innovations and development of class rules and other safety regulations, which are traditionally developed in reaction to specific casualties, thus following an inductive approach (reasoning from specific to general). Logic says that when the inductive approach is applied exemptions can occur and modification of the existing state is required. Bulk carriers, tankers and Ro-Ro vessels, their casualties, and the reaction to casualties, are good examples of this approach. The occurring exemptions (casualties) are information that the safety regulations developed basing on the inductive approach are not fully harmonized with the sea environment and ship operation, as the sea environment and ship operation underlie the majority of casualties.
A technically safe vessel is a necessary condition for safe shipping, whereas the sufficient condition to be met is safe ship operations, which involves improved performance of the so-called human factor. The paper presents, on the example of construction of bulk carriers, the novel trend in the rules development process.
