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

3-42 API RECOMMENDED PRACTICE 581
f
is a gas release constant used in NH3 and Cl releases for the Level 1 toxic consequence area
analysis
AIT
fact is the AIT consequence area blending factor
fact
di
is the release magnitude adjustment factor, based on the detection and isolations systems
present in the unit.
IC
fact is the continuous/instantaneous consequence area blending factor determined for each release
n
hole size, associated with the n th release hole size
fact
mit is the consequence area adjustment factor, based on the mitigation systems present in the unit.
frac is the fraction of the released liquid pool that evaporates, needed to estimate the volume of
evap
material for environmental cleanup
FC is the final financial consequence, $
FC is the financial consequence of damage to surrounding equipment on the unit, $
affa
FC
cmd is the financial consequence of component damage, $
FC
environ is the financial consequence of environmental cleanup, $
FC is the financial consequence as a result of serious injury to personnel, $
inj
FC is the financial consequence of lost production on the unit, $
prod
g
Is a gas release constant used in acid and caustic releases for the Level 1 area consequence
analysis
2
g
c
is the gravitational constant = 1.0( kg m) ( N s )
2
− − ⎡32.2( lbm − ft) ( lbf
−s
)
⎣
⎤
⎦
gff
n
are the generic failure frequencies for each of the n release hole sizes selected for the type of
equipment being evaluated
gff
total is the sum of the individual release hole size generic frequencies
h
is a gas release constant for acid and caustic for the Level 1 area consequence analysis
holecost
n is the equipment repair cost, provided for each of the release hole sizes selected, $
injcost is the cost associated with serious injury or fatality of personnel, $
k
is the release fluid ideal gas specific heat capacity ratio, unitless