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

RISK-BASED INSPECTION METHODOLOGY, PART 3—CONSEQUENCE OF FAILURE METHODOLOGY 3-23
2) Calculate the consequence area using Equation (3.43).
AINL−CONT
b
( )
⎤ ( )
CA = ⎡
⎢
a ⋅ rate
⎥
⋅ − fact
⎣
⎦
AINL−CONT
inj, n n
1
mit
(3.43)
i) STEP 8.9—For each release hole size, calculate the personnel injury consequence areas for Autoignition
AIL CONT
Likely, Continuous Release (AIL-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.
a a −
AIL CONT
=
inj
(3.44)
b b −
AIL CONT
=
inj
(3.45)
2) Calculate the consequence area using Equation (3.46).
AIL−CONT
b
( )
⎤ ( )
CA ⎡a rate fact
⎢⎣
⎥⎦
AIL−CONT
inj, n
= ⋅
n
⋅ 1−
mit
(3.46)
j) STEP 8.10—For each release hole size, calculate the personnel injury consequence areas for
Autoignition Not Likely, Instantaneous Release (AINL-INST), ,
AINL−INST
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.
a a inj
AINL−INST
= (3.47)
.
b b inj
AINL−INST
= (3.48)
2) Calculate the consequence area using Equation (3.49).
1 fact
CA − a ( mass
− n )
⎛ −
= ⎡ ⋅ ⎤⋅ ⎞
⎣ ⎦ ⎜ ⎟
(3.49)
⎝ ⎠
AINL INST AINL INST
b
mit
inj,
n
⎢
⎥ eneffn
k) STEP 8.11—For each release hole size, calculate the personnel injury consequence areas for
AIL INST
Autoignition Likely, Instantaneous Release (AIL-INST), 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.
AIL INST
=
inj
(3.50)
a a −
b b −
AIL INST
=
inj
(3.51)