API RP 581 - 3rd Ed.2016 - Add.2-2020 - Risk-Based Inspection Methodology

PART 1—INTRODUCTION TO RISK-BASED INSPECTION METHODOLOGY 1-29
10,000
3.1E-01
5
High
Damage Factor / POF Category
1,000
4
100
3
10
2
1
Low
Medium
Medium-High
3.1E-02
3.1E-03
3.1E-04
3.1E-05
Probability of failure, events/year
1
(gff = 3.06E-5)
0
3.1E-06
10 A 100 B 1,000 C 10,000 D 100,000 E 1,000,000
Consequence of Failure, ft 2 / COF Category
0.1 ft2/year 10 ft2/year 1,000 ft2/year
Figure 4.4—Example Iso-risk Plot for Consequence Area