With rational mathematically based analytical tools such as fault tree or Bayesian network based approaches it is possible to analyse the effect of Risk Control Options (RCO) as for example:
Change in collision probability due to change in route such as:
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Effect of vessel traffic separation schemes
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Effect of aids to navigation
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Effect of vessel traffic systems (VTS)
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Effect of Electronic Navigational Charts (ENC)
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Effects of pilots in open waterways
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Effect of weather and visibility conditions
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Effect of speed reduction
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Effect of better sea charts
Change in causation factor due to changes in human behaviour such as:
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Effects of manning
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Effect of simulator training [30]
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Effect of crew schedule to avoid fatigue of crew
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Effect of psychological screening of navigators
Changes in ship design such as:
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Effects of bridge layout and technical equipment such as radar systems
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Effect of GPS for position fixing and ECDIS
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Effect of AIS integrated with radar
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Effect of redundancy of navigational equipment
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Effect of ship’s speed on causation factor (time to react), see Fig. 8
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Effect of improved manoeuvrability on causation factor (time to react)
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Effect of propulsion redundancy – twin screw vessels
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Effect of reduced probability of engine blackout or steering machine failure