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

RISK-BASED INSPECTION METHODOLOGY, PART 2—PROBABILITY OF FAILURE METHODOLOGY 2-121
Number of inspections
Operating temperature, °C (°F)
The number of inspections in each effectiveness category that have been
performed.
Determine the expected operating temperature (consider normal and nonnormal
operating conditions).
Table 17.2—SCC Susceptibility—External ClSCC
Operating Temperature SCC Susceptibility As a Function of Driver 1
°C °F Severe Moderate Mild Dry
<49 120 None None None None
49 to 93 120 to 200 High Medium Low None
93 to 149 200 to 300 Medium Low Low None
>149 >300 None None None None
NOTE 1
Driver is defined as the atmospheric condition causing the SCC.
Table 17.3—Severity Index—External ClSCC
Susceptibility
Severity Index—S VI
High 50
Medium 10
Low 1
None 0