Unit 2 - Risk, Accidents and Human Factors Flashcards
What is the difference between risk and hazard?
A hazard is a potential source of harm or a situation with the potential to cause harm, damage, or adverse effects, whereas risk is the likelihood or probability of the occurrence of harm or adverse effects resulting from a hazard. It involves the combination of the probability of an event and the severity of its consequences.
What are hazards?
Sources of potentially damaging energy which exist either naturally or as a result of humankind’s modification of the naturally occurring world…where damage (injury) is the result of an incident energy whose intensity at the point of contact with the recipient exceed the damage threshold of the recipient
The definition of a hazard as a source of potentially damaging energy is the basis for several models of accident causation (refer Viner, 1991)
Give an example of something being a hazard.
(find a different one) Pipelines containing flammable oil under pressure are not in themselves
hazardous, what makes them hazardous is their potential to leak allowing the contents to come into contact with an ignition source, which can result in a fire or to cause harm to people in close proximity through impact or to harm the marine environment through leakage. If there is no context (no source of
ignition, no people in proximity, no proximity to marine environment) then there is no hazard in the event of a release of energy (i.e. pipeline leaks).
Why can it be difficult to identify hazards?
- Interconnectedness of Hazards:
Hazards are often interconnected, and the presence of one hazard can exacerbate or lead to the emergence of others. Identifying these relationships and understanding the cumulative effect of multiple hazards can be challenging.
- Complacency and Familiarity:
In environments where processes have been stable for a long time, individuals may become complacent or overly familiar with their surroundings. This familiarity can lead to oversight, where potential hazards are not recognized due to a lack of fresh perspective.
- Uncertainty in Dynamic Environments:
Some environments, such as those affected by weather conditions or external factors, are dynamic and unpredictable. Identifying hazards in these contexts can be challenging as conditions change rapidly.
- Unpredictable Human Behavior:
Human factors, including behavior, can introduce unpredictability. Identifying potential hazards related to human actions, errors, or variations in performance requires a nuanced understanding of the individuals involved and their responses to different situations.
What are the hazardous conditions to which ships may be exposed?
§ The transport of goods by sea is relatively hazardous when compared to other modes of transport. The hazards to which ships may be exposed are:
§ weather and sea conditions
§ The ship itself (structural failure, stability issues, fire)
§ proximity of navigational hazards such as shallow water, other ships, fixed and floating objects and ice.
§ carriage of flammable materials mainly cargo and fuel.
§ the proximity of dangerous goods and substances as cargo which are
hazardous to health, the ship itself and the environment.
§ the people who work on ships, if they are fatigued or not mentally or physically competent to perform their duties.
§ the condition of machinery; it’s design, reliability, availability and maintainability.
§ more recently computer hackers and those with malintent intent.
What is the relationship between hazards, accidents and
consequences?
The relationship between hazards, accidents, and consequences is integral to understanding the factors that contribute to incidents and their subsequent outcomes. (explain how one leads to another)
Explain the James Reason Swiss Cheese Model
The Swiss Cheese Model, developed by James Reason, is a conceptual framework used to illustrate the layers of defense within a system designed to prevent or mitigate accidents. In this model, each layer of defense is represented as a slice of Swiss cheese, and the holes in the cheese symbolize potential weaknesses or vulnerabilities in the barriers. The model distinguishes between two types of failures: active failures, which are immediate and observable actions that can contribute to incidents, and latent conditions, which are underlying factors that may not have an immediate impact but influence the likelihood of active failures. The idea is that for an accident to occur, the holes in multiple layers of defense must align, allowing a hazard to penetrate the system. The Swiss Cheese Model emphasizes the importance of having multiple layers of defense, continuous improvement, and a proactive approach to identifying and addressing weaknesses in order to enhance overall safety and prevent adverse outcomes.
How and why to understand of accidents with regard to systems, functions and hazards?
To have an understanding of maritime incidents and how they develop, it is important not just to understand the general risk picture but to recognize that they are complex phenomena that can rarely be fully explained simply.
It is important to to have a full appreciation of:
§ the performance of functions that need to be carried out by
humans or control systems to achieve the goal of getting a ship
safely from from its origin to its destination with payload
§ the reliability, availability and maintainability of systems that
support these functions
§ the proximity of hazards needing to be guarded against
What are the types of functions and systems important for safe ship operation?
what are the effects on a ship form grounding on rocky bottom?
Bottom damage in this case can result in significant indentation of the bottom shell plating and the bilge
keel, propeller or rudder.
§ In more severe grounding cases, the hull integrity can be breached due to cracks or tears in hull, and
there may be significant internal structural damage such as deformed transverse and longitudinal frames. The integrity of internal watertight bulkhead, separating compartment’s may be compromised and this can affect the ship’s stability.
§ The area of damage can be extensive.
Describe collision and the impacts
§ Collisions between ships can result in significant localised damage depending on:
§ the angle of impact between the two ships § contact location § relative speed and course § mass (displacement) of both ships
§ A glancing blow may result in just minor damage which is limited to the shell plating and deck fittings such as handrails.
§ Collisions which cause the most damage are those: § when ships impact at right angles to each
other
§ where there is end
-on contact when ships are
approaching on reciprocal courses. i.e., bow to bow contact
Ships are structurally much stronger in the bow area which is better able to resist the impact of a collision
and sustain least damage.
§ Under SOLAS, all ships are required to be fitted with a collision bulkhead which is the first watertight transverse bulkhead from the bow.
A collision bulkhead is the the first
watertight bulkhead in the forward part of a ship designed to keep out water in the event of a collision.
