W6 wp52plenary

Slide1: 

Brussels, 19th-20 th February 2002 WP 5:Safety and Environmental Assessment Methods (for Design of Ships) THEMES network meeting

Maritime Safety: 

Maritime Safety Safety concerns have been reflected in the attention given to: - design and building activities - operation of the ships - education and training of the ship operators Penalties for the Lack of Safety: - lives lost, - damage to the environment and to cargo

Risk Assessment in Maritime Industry: 

Risk Assessment in Maritime Industry Accident Statistics Risk of Ship Collision, Grounding and Foundering - Risk of Fire and Explosion - Formal Safety Assessment (FSA) Risk of Structural Failure

Risk Assessment in Maritime Industry: 

Risk Assessment in Maritime Industry Accident Statistics Provide an overall quantification of the risks levels existing in maritime transportation Allow the identification of the time evolution of the levels of safety, the differentiation of safety in the different types of ships, ship sizes, ages, etc Allow the identification of the main modes of failure

Accident Statistics (cont.): 

World fleet. Source: Lloyds "World Fleet Statistics” Accident Statistics (cont.)

Accident Statistics (cont.): 

Annual rate of total losses Source: Lloyds "World Casualty Statistics” Accident Statistics (cont.)

Accident Statistics (cont.): 

Distribution of annual average rate of the first event by ship type Source: Lloyds "World Casualty Statistics” Accident Statistics (cont.)

Accident Statistics (cont.): 

Percentage of the principal causes of ship accidents Source: UK P&I Reports Accident Statistics (cont.)

Accident Statistics (cont.): 

Geographical distribution of the frequency of weather related accidents n=250 Accident Statistics (cont.)

Risk of ship collision, grounding and foundering : 

Risk of ship collision, grounding and foundering - Probabilistic evaluation of damage survivability of cargo ships larger than 100m in length was in adopted in 1990 (SOLAS) - Probabilistic evaluation of the effect of the subdivision on the expected oil outflow from damage tankers (IMO, 1995) Probabilistic standards for intact ship stability Probabilistic approach to damage stability resistance based on the watertight subdivision of the ship Ship Capsize under beam seas and winds Pure loss of stability when the ship is sailing with seas from astern Surf riding in the waves

IMO Guidelines for probabilistic evaluation of tanker subdivision: 

IMO Guidelines for probabilistic evaluation of tanker subdivision - Probability of collision - depends on the area in which the ships are sailing and on other aspects related with the ship operation - Conditional probability of damage location and size - depends on the type and size of the ships involved in the collision as well as on their speed and relative heading. - Conditional probability of the ship floating after the damage - depends on the design features of the ship. Ex.: depth and extend of the double hull Pollution Prevention Index - Measure of merit of the oil outflow performance of the tanker

Probabilistic ship design against structural failure : 

 Reliability Assessment of the primary ship structure - Development of probabilistic models for Ultimate vertical bending strength of the ship - Development of probabilistic formulations to model the effect of strength degradation due to fatigue and corrosion. - Development of probabilistic models for still water and wave induced bending moments Probabilistic ship design against structural failure  Reliability Assessment of ship structural components

Reliability Assessment of the primary ship structure (cont.): 

Reliability Assessment of the primary ship structure (cont.) Assessment of the notional probability of structural failure that result from different ship types Assessment of the notional probability of structural failure that result from different concepts of the same ship Quantification of the changes in notional probability of structural failure that result from ships being subjected to different wave environments Probabilistic assessment of partial safety factors Assessment of the time dependent reliability of the ship due to the effect of strength degradation due to fatigue and corrosion Structural maintenance planning Applications:

Reliability Assessment of the primary ship structure (cont.): 

Reliability Assessment of the primary ship structure (cont.) Isolines of relative probability of hull failure in European waters for a tanker 1.00 0.95 0.90 0.85 0.80 0.70 0.60 0.55 0.50 0.45 0.40 0.30 0.20 0.10 0.00

Failure Mode and Effect Analysis: 

Failure Mode and Effect Analysis FMEA is required under the International High-Speed Code for (IMO 1995): Directional control systems, Machinery, Electrical installations Stabilisation systems FMEA can be used to identify single catastrophic failures and also failures that are not immediately detected FMEA, is used to identify design and also operating and maintenance failure modes.

Formal Safety Assessment : 

Formal Safety Assessment Rational and systematic process for assessing the risks associated with shipping activity and for evaluating the costs and benefits of IMO's options for reducing these risks. Interim Guidelines were adopted in 1997 and IMO Member States have been invited to carry out trials and report back to IMO. FSA consists of five steps: Identification of hazards Assessment of risks (evaluation of risk factors); Risk control options Cost benefit assessment Recommendations for decision-making - information about the hazards, their associated risks and the cost effectiveness of alternative risk control options is provided

Formal Safety Assessment (cont.): 

Formal Safety Assessment (cont.)

Formal Safety Assessment (cont.): 

Formal Safety Assessment (cont.) Applications of FSA: Within IMO several studies have already been performed using FSA to support decisions about implementation of international regulations - UK study of safety of high-speed passenger catamaran vessels, concentrating on the safety of passengers and crew. - Safety assessment of high-speed craft operations performed between the Scandinavian Countries. - Germany study on disabled oil tankers in particular their Emergency Propulsion and Steering Devices. - A feasibility and rentability study of Emergency Propulsion Devices (EPD) using the FSA methodology carried out by Germany - Two studies have been made about the possibility of requiring helicopter-landing areas to be installed in ships for emergency evacuation (UK) - An international FSA study is currently being undertaken on the safety of Bulk Carriers coordinated by UK, under the auspices of the IMO

Risk acceptance criteria: 

Risk acceptance criteria The IMO FSA guidelines suggest that both the individual and the societal types of risk should be considered for a crew member for a passenger and for third parties Individual risks Fatal Accident Rate (FAR) represents the probability of a person being killed when actually doing a specific activity Social Risks F-N curves relates the frequency (F) and the number of fatalities in accidents

Risk acceptance criteria (cont.): 

Risk acceptance criteria (cont.) Individual risk criteria ( UK Health & Safety Executive, 1999)

Risk acceptance criteria (cont.): 

Risk acceptance criteria (cont.) Societal risk acceptance criteria curve for K=1, A=0.1 and A=0.001

Concluding Remarks: 

Concluding Remarks Applications of quantified risk analysis to commercial shipping are most likely to involve marine operations with significant consequences in the event of an accident The approach of proactively managing risk is now being used in shipping. This not only reflects the importance to safety of both the human being and the complexity of the technology in the system, but also the financial importance of delivering a completely integrated functioning system to time and cost. A number of potential applications of quantified risk assessment within the maritime transportation activity have been identified

Slide23: 

Brussels, 19th-20 th February 2002 WP 5:Safety and Environmental Assessment Methods (for Design of Ships) THEMES network meeting