Root Cause Analysis

APPENDICES

A. Answer Keys

1. Check for Understanding

# Answer

1. lost opportunities; increased risk


2. True


3. Any of the following:
   
   
   • Sequence of Events
   
   
   • Event and Causal Factor Analysis (ECF)
   
   
   
   


4. Any of the following:
   
   
   • Five Why, Root Cause Problem Elimination (RCPE)
   
   
   • Fault Tree Analysis (FTA)
   
   
   • Logic Tree Analysis (LTA)
   
   
   • Cause and Effect
   
   
   • Failure Modes, Effects, and Criticality Analysis (FMECA)
   
   
   
   


5. Five Why


6. Event and Causal Factor Analysis (ECF)


7. Change Analysis


8. Fault Tree Analysis (FTA)


9. Five Why


10. Cause and Effect/Ishikawa/Fishbone Diagram


11. Methods, Materials, Manpower Machinery, Measurements, and
    Environment


12. Failure Modes, Effects, and Criticality Analysis (FMECA)


13. The RPN is the product of the likelihood that the failure will occur, the
    likelihood that the failure can be detected, and the severity damage
    that a failure may cause. (or its equivalent formula).


14. Sequence of Events displaying the sequence of events leading to a
    particular failure or event in a graphical manner on a single path while
    ECF displays the same but on multiple paths.


15. Five Why asks Why questions after problem is identified while RCPE
    asks How Can questions.

# Answer

16. FTA is an expansion of the Five Why method by adding branches to the
    initial ‘why’ tree. This method looks for actions and conditions.


17. Both methods look at undesirable results in a branched method but LTA
    does so with the addition of logic statements (‘Ands’ and ‘Ors’).

2. Change Analysis Exercise – The Anchor And My Tugboat

Change Factor Difference/Change Effect Questions to Answer

What

Anchor falling on

tugboat

Damaged

equipment and

injured personnel

Any primary

equipment failure

led to anchor falling

inadvertently?

(Conditions, occurrence,

activity, equipment)

When

Time of occurrence -

time of day/week

Ship and tugboat

personnel

stressed or not in

appropriate state

of mind

What was likely

state of mind of

personnel at time

of incident?

(Occurred, identified,

plant status, schedule)

Where

1. Event occurrence
   in fog/ reduced
   visibility conditions


2. Unfamiliar ship in
   unfamiliar port


3. Tugboat
   obscured


4. Unfamilarity
   with
   surroundings


5. Validate adverse
   weather conditions.


6. Check shipping
   manifest and port
   reports/
   documentation

(Physical location,

environmental conditions)

How (^) 1. Tugboat should not
be directly under the
anchor 2. Lack
of/miscommunication
between vessels 3.
Release of anchor
while ship is being
maneuvered

1. Tugboat in
   wrong location


2. Inability to
   prevent adverse
   consequence
   from happening


3. Anchor falls on
   tugboat


4. SOP? 2. Was
   communication
   method ineffective
   or not used? 3.
   Failed brake on
   anchor?

(Work practice,

ommission, extraneous

action, out of sequence

procedure)