CHAPTER 12 - RISK ASSESSMENT

Question 1

Originated in the aerospace industry and has been used extensively by the
nuclear power industry to qualify and quantify the hazards and risks associated with
nuclear power plants.

Answer 1

C. Fault trees

Question 2

____________ begin with an initiating event and work toward the top event.

Answer 2

B. Event Trees

Question 3

. __________ is a semi-quantitative tool for analyzing and assessing risk. This method
includes simplified methods to characterize the consequences and estimate the frequencies.

Answer 3

C. LOPA

Question 4

The actual risk of a process or plant is usually determined using _________.

Answer 4

C. QRA or LOPA

Question 5

A method that identifies where operations, engineering, or management systems can be
modified to reduce risk.

Answer 5

D. QRA

Question 6

Events in a fault tree are not restricted to hardware failures. They can also include
______________

Answer 6

software, human, and environmental factors.

Question 7

A fault event that needs no further definition.

Answer 7

B. BASIC Event

Question 8

The resulting output event requires the occurrence of any individual input event

Answer 8

D. OR Gate

Question 9

The resulting output event requires the simultaneous occurrence of all input events

Answer 9

B. AND Gate

Question 10

The event that results from the interaction of a number of other events.

Answer 10

A. INTERMEDIATE EVENT

Question 11

Failures that are immediately obvious.

Answer 11

B. Revealed failures

Question 12

Sum of the period of operation and downtime.

Answer 12

D. MTBF

Question 13

A failure of equipment without the operator being aware of the situation.

Answer 13

A. Unrevealed failure

Question 14

All process components demonstrate unavailability as a result of a failure.

Answer 14

A. Probability of Coincidence

Question 15

The loss of electrical power or a loss of instrument air. A utility failure of this type can
cause all the control loops to fail at the same time.

Answer 15

B. Common mode failure

Question 16

The approach offers details on the possibility of a failure as well as how it could happen.

Answer 16

A. Event trees

Question 17

Depends on the hazards of the process and on the potential for economic losses.

Answer 17

D. Degree of Redundancy

Question 17

__________ lines are drawn from these two states to the next safety function.

Answer 17

B. Horizontal

Question 17

The event trees is written from left to ______.

Answer 17

A. Right

Question 17

Among the 4 Safety Functions, which function is the high-temperature alarm?

Answer 17

A. First safety function

Question 18

_____ are collected on the failure rate of a particular hardware component

Answer 18

A. Data

Question 19

on average, the component fails after a certain period of time.

Answer 19

A. Average failure data

Question 20

The complement of the reliability.

Answer 20

C. Failure Probability

Question 21

The __________ is defined as the derivative of the failure probability.

Answer 21

B. Failure Density Function

Question 22

This means that a failure of any single component in the ______ of components will result in failure of the process.

Answer 22

D. Series

Question 23

___________ would depend on the manufacturer, materials of construction, the design, the environment, and other factors.

Answer 23

C. Actual Values

Question 24

______ is the reliability of an individual process component.

Answer 24

A. Ri

Question 25

_______is the failure probability of each component.

Answer 25

Pi

Question 26

_______ represents the fraction of the total area under the failure density function between time to and t1 .

Answer 26

A. Integral

Question 27

The time interval between two failures of the component is called the ___________.

Answer 27

C. MTBF

Question 27

The consequences and effects are approximated by categories, the frequencies are estimated, and the effectiveness of the protection layers is also approximated.

Answer 27

B. LOPA

Question 28

It begins with a top event and works backward toward the initiating event. (deduction)

Answer 28

C. Fault Trees

Question 29

In short terms, it means “LOPA”

Answer 29

A. Layer of Protection Analysis

Question 30

In short terms, it means “QRA”

Answer 30

C. Quantitative Risk Analysis

Question 31

The independent protection layer (IPL) varies from

Answer 31

A. 10^-1 to 10^-5

Question 32

The results should always be more conservative than those from a QRA.

Answer 32

A. LOPA

Question 33

if the LOPA results are unsatisfied or if there is any uncertainty in the results, then a full ____ may be justified

Answer 33

D. QRA

Question 33

The primary purpose is to determine whether there are sufficient layers of protection against a specific accident scenario.

Answer 33

A. LOPA

Question 34

study the consequences of these releases are quantified using dispersion modeling and a detailed analysis to determine the downwind consequences as a result of fires, explosions, or toxicity.

Answer 34

D. QRA

Question 35

The concept of ___ is also used when designing emergency shutdown systems called safety instrumented functions. (SIFs)

Answer 35

B. PFD