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

3-118 API RECOMMENDED PRACTICE 581
poi is the probability of ignition given a two-phase release associated with the n th release hole size
2,n
poii
is the probability of immediate ignition given ignition
ait
poii is the probability of immediate ignition given ignition if the fluid were to be released at or above
its AIT , assumed = 1.0
poii is the probability of immediate ignition given ignition if a liquid were to be released at ambient
amb
ln ,
temperature associated with the n th release hole size
poii is the probability of immediate ignition given ignition if a vapor were to be released at ambient
amb
vn ,
temperature associated with the n th release hole size
poii is the probability of immediate ignition given ignition of a liquid release associated with the n th
ln ,
release hole size
poii is the probability of immediate ignition given ignition of a vapor release associated with the n th
vn ,
release hole size
poii is the probability of immediate ignition given ignition of a two-phase release associated with the
2,n
n th release hole size
ppool is the probability of a pool fire given a release of a flammable liquid associated with the n th
ln ,
release hole size
ppool
n
is the probability of a pool fire given a release associated with the n th release hole size
ppool is the probability of a pool fire given a release of a flammable vapor associated with the n th
vn ,
release hole size
psafe
n
is the probability of a safe release given a release associated with the n th release hole size
psafe is the probability of a safe release given a vapor release associated with the n th release hole
vn ,
size
psafe is the probability of a safe release given a release of a flammable two-phase fluid associated
2,n
with the n th release hole size
ptox
n
pvce
n
is the probability of a toxic release given a release associated with the n th release hole size
is the probability of a VCE given a release associated with the n th release hole size
pvce is the probability of a VCE given a release of a flammable vapor associated with the n th release
ln ,
hole size
pvce is the probability of a VCE given a vapor release associated with the n th release hole size
vn ,