7. Human Error and Mitigation Strategy

Question 1

Cos’è la root cause analysis?

Answer 1

Investigate the accident until the single, underlying cause is found

Question 2

Spiega i Five Whys

Answer 2

Basically, it means that when searching for the reason, even after you have found one, do not stop: ask why that was the case.

Question 3

Quali sono i 2 tipi di errore?

Answer 3

Slips (lapsus), mistakes (errori cognitivi)

Question 4

Cos’è uno slip?

Answer 4

With a slip, the action performed is not the same as the action that was intended.

Question 5

Quanti tipi di slips ci sono?

Answer 5

Action-based slips
Memory-based slips

Question 6

Cos’è un mistake

Answer 6

A mistake occurs when the wrong goal is established or the wrong plan is formed.

Question 7

Quanti tipi di mistakes ci sono?

Answer 7

rule-based mistakes,
knowledge bases mistakes,
memory lapses

Question 8

Tra il tuo obiettivo e il mondo esterno come si collocano gli splis e i mistakes visti?

Answer 8

Where slips and mistakes originate in the action cycle.
Figure A shows that action slips come from the bottom four stages of the action cycle and mistakes come from the top three stages. Memory lapses at the higher levels lead to mistakes and lapes at the lower levels lead to slips.

Question 9

Come fare Error Prevention?

Answer 9

• Understand the causes of error and design to minimize those causes.
• Do sensibility checks.
• Make it possible to reverse actions
• Make it easier for people to discover the errors that do occur, and make them
  easier to correct.
• Don’t treat the action as an error;

Question 10

Come fare Error Mitigation?

Answer 10

The Swiss cheese metaphor suggests several ways to reduce accidents:
* Add more slices of cheese.
* Reduce the number of holes (or make the existing holes smaller).
* Alert the human operators when several holes have lined up.
Each of these has operational implications:
More slices of cheese means mores lines of defense (more checks and control
steps)
Reducing the number of critical safety points where error can occur is like
reducing the number or size of the holes (Reduce distraction and design for
error mitigation)