Probability of Occurrence Classifications: May be expressed in qualitative terms like Extremely Improbable, Extremely Remote, Remote, Reasonably Probable or Frequent
Probability of
Occurrence
classification
|
Extremely improbable
|
Extremely
remote
|
Remote
|
Reasonably probable
|
Frequent
|
Qualitative definition
|
Should virtually never occur in the whole fleet life. |
Unlikely to occur when considering several systems of the same type, but nevertheless, has to be considered as being possible |
Unlikely to occur during total operational life of each system but may occur several times when considering several systems of the same type |
May occur once or a few times during the total operational life of a single system |
May occur once or several times during operational life |
Quantitative definition
|
< 10 9 per flight hour |
10 7 to 10 9 per flight hour |
10 5 to 10 7 per flight hour |
10 3 to 10 5 per flight hour |
10 3 per flight hour |
NOTE: As there are usually a number of causal factors that contribute to the risk budget of an undesired event, the probability of each item is (arbitrarily) set one or two orders of magnitude greater than in the table above.
Speak Your Mind
You must be logged in to post a comment.