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Guidance on Risk Analysis and Safety Implications of a Large Liquefied Natural Gas (LNG) Spill Over Water


Quiz Questions

1.Risks from a potential LNG spill over water could be reduced through a combination of approaches, including 1) reducing the potential for a spill, 2) reducing the consequences of a spill, 3) improving LNG transportation safety equipment, security, or operations to prevent or mitigate a spill.
True
False
2. Some of the special features of LNG ships include- (1) Construction of specialized materials and equipped with systems designed to safely store LNG at temperatures of -260 °F (-162.2°C). (2) All LNG ships are constructed with double hulls. This construction method not only increases the integrity of the hull system but also provides additional protection for the cargo tanks in the event of an accidental collision.
True
False
3. LNG is considered an inflammable liquid.
True
False
4.______________ is defined as the potential for suffering harm or loss and is often quantified as the product of the probability of occurrence of a threatening event times the system vulnerability to that event and the consequences of that event.
Risk
Spill
5.Risk assessment and risk management approach is represented in ___________________.
Figure 3
Figure 4
Figure 5
6. Anatomy of an LNG Spill on Water is represented in ____________________________.
Figure 3
Figure 4
Figure 5
7.Rapid Phase Transitions occur when the temperature difference between a hot liquid and a cold liquid is sufficient to drive the cold liquid rapidly to its superheat limit, resulting in spontaneous and explosive boiling of the cold liquid.
True
False
8. In risk reduction strategies, accidental mechanisms can often produce greater consequences than intentional mechanisms because the perpetrator can maximize the effects of an attack by choosing the time and place.
True
False
9. __________________could occur between an LNG tanker and a fixed object or between a boat and an LNG tanker.
Ramming
Triggered explosion
10.External terrorist attacks could come from a number of avenues, including attack of the LNG ship with a wide range of munitions or bulk explosives. A U.S.S Cole-type attack is often suggested as a potential attack scenario, as well as attacks with munitions such as rocket propelled grenades, or missiles or attacks by planes.
True
False
11. The duration of the fireball from combusting clouds is given as t = 4.6M 0.2 in which the fuel mass, M, is in metric tons and the time, t, is given in seconds.
True
False
12. Figure 14 represents___________________________________.
The fireball duration and radius as a function of fuel mass
The dispersion distances to LFL for potential spills
13.Figure 12 represents___________________________________.
The dispersion distances to LFL for potential spills
The fracture toughness of low alloy carbon steels
14. Shallow-layer models use equations that assume the lateral dimensions are much greater than the vertical dimension, which is representative of dense gas releases where low wide clouds result.
True
False
15. Gaussian puff models are typically for buoyant or neutrally buoyant releases, such as from an elevated stack source.
True
False