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

3-22 API RECOMMENDED PRACTICE 581
b b −
= (3.33)
AIL CONT
cmd
2) Use Equation (3.34) to calculate the consequence area.
b
( ) ( )
CA = a rate ⋅ − fact
(3.34)
AIL−CONT
cmd , n n
1
mit
f) STEP 8.6—For each release hole size, calculate the component damage consequence areas for
AINL−INST
CA cmd n
Autoignition Not Likely, Instantaneous Release (AINL-INST),
,
.
1) Determine the appropriate constants, a and b, from the Table 4.8. The release phase as determined
in STEP 1.4 will be needed to assure selection of the correct constants.
AINL−INST
= (3.35)
a a cmd
b b cmd
AINL−INST
= (3.36)
2) Use Equation (3.37) for the consequence area.
CA
b 1 factmit
a ( massn
)
⎛ −
− = ⋅⎜ ⎞
⎟
⎝ eneffn
⎠
AINL INST
cmd , n
(3.37)
g) STEP 8.7—For each release hole size, calculate the component damage consequence areas for
AIL INST
Autoignition Likely, Instantaneous Release (AIL-INST), CA − cmd , n .
1) Determine the appropriate constants, a and b, from the Table 4.8. The release phase as determined
in STEP 1.4 will be needed to assure selection of the correct constants.
a= a −
(3.38)
AIL INST
cmd
b= b −
(3.39)
AIL INST
cmd
2) Use Equation (3.40) to calculate the consequence area.
CA
b 1 factmit
a ( massn
)
⎛ −
− = ⋅⎜ ⎞
⎟
⎝ eneffn
⎠
AIL INST
cmd , n
(3.40)
h) STEP 8.8—For each release hole size, calculate the personnel injury consequence areas for Autoignition
AINL−CONT
Not Likely, Continuous Release (AINL-CONT), CA inj , n .
1) Determine the appropriate constants, a and b, from the Table 4.9. The release phase as determined
in STEP 1.4 will be needed to assure selection of the correct constants.
AINL−CONT
= (3.41)
a a inj
b b inj
AINL−CONT
= (3.42)