Quiz 5

Question 1

What are the 2 main factors that caused the Union Carbide disaster?

Answer 1

1. Use of a dangerous chemical when alternative was available
2. Poor attention to safety during operations (supervisor ignoring a small leak, alarm that workers ignored)

Question 2

Why is safety so important in engineering?

Answer 2

1. Engineering won’t benefit humanity if harm is caused
2. Professional privileges would disappear if public perceived danger
3. Safety is an economic good: increasing productivity and reduced healthcare costs
4. Moral integrity of engineers

Question 3

What formula defines risk?

Answer 3

Risk = likelihood of event x severity if event occurs
Risk = p(E) * p(C|E)

Question 4

What are the 3 techniques for assessing risk in “the risk framework”?

Answer 4

1. List possible outcomes, their likelihood, and their severity
2. Event trees to find the probability of major events
3. Fault diagram to determine what causes a failure

Question 5

Name some examples of non-prototypical designs?

Answer 5

1. My capstone project
2. bridge designs
3. autonomous cars

Question 6

How does the Hurricane Katrina disaster show a flaw in the risk framework?

Answer 6

The risk of flooding was underestimated by those who did not have enough experience with flood protection systems. Thus, the risk framework had large error

Question 7

What are the 6 situations that tight-coupling occurs?

Answer 7

Parts are related such that:
1. The process cannot be slowed
2. The order of sequences is fixed
3. There is a single way to achieve the goal
4. There is little slack in resources (supplies, equipment, and personnel)
5. 5. The only buffers and redundancies are those that are built-in to the system
6. There is limited opportunity to substitute resources

Question 8

Why do complex-adaptive systems fail?

Answer 8

Interdependency creates vulnerability to failure at all scales.

Question 9

How can complex systems be made safer?

Answer 9

Reduce complexity and manage the system with caution every day by:
1. patient observation
2. testing and revising understanding
3. obtaining good data
4. developing humility to accept weakness and promote learning
5. working across disciplines
6. obtaining clarity on the desired goals

Question 10

What factors do resilience depend on?

Answer 10

1. drop in performance after a shock
2. recovery time
3. window for analysis
4. initial value for performance

Question 11

How are risk-cost-benefits compared?

Answer 11

Each aspect is converted to monetary value

Question 12

What are 4 indirect approaches to safety?

Answer 12

1 rules
2. regulations
3. policies
4. procedures

Question 13

What were some of the engineering failures behind the collapse of the FIU pedestrian bridge?

Answer 13

1. Peer review was done by an unqualified firm
2. Inspection done by 3rd party that did not understand the new design
3. Failure to acknowledge importance of large, propagating cracks

Question 14

What are 3 human mistakes in risk management?

Answer 14

1. ignorance
2. complacency
3. overconfidence

Question 15

Name the 4 individual factors in engineering failure

Answer 15

1. bounded rationality
2. pressure from non safety goals
3. inconsistent habits
4. hubris / overconfidence

Question 16

Name the 6 organizational factors in engineering failure

Answer 16

1. group dynamics / organizational structure
2. pressure from non safety goals
3. insufficient safeguards
4. organizational complexity
5. tendency of systems towards disorder
6. organizational inattention to safety
7. hubris / overconfidence

Question 17

What were some human factors to the flooding caused by hurricane Katrina?

Answer 17

1. multiple, uncoordinated entities in charge of system
2. lack of peer review
3. flawed funding process

Question 18

Which human factors led to the failure of the Challenger space shuttle launch?

Answer 18

1. Overconfidence
2. pressure from non safety goals