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

RISK-BASED INSPECTION METHODOLOGY, PART 3, ANNEX 3.A—BASIS FOR CONSEQUENCE METHODOLOGY 3.A-19
Table 3.A.3.6—Specific Event Probabilities—Instantaneous Release Autoignition Not Likely
ParFluid
C1-C2
C3-C4
Probability of
Ignition
Final Liquid State—Processed Above AIT
Probabilities of Outcome
VCE Fireball Flash Fire Jet Fire Pool Fire
C5 0.1 0.1
C6-C8 0.1 0.1
C9-C12 0.05 0.05
C13-C16 0.05 0.05
C17-C25 0.02 0.02
C25+ 0.02 0.02
H2
H2S
DEE 0.9 0.9
Methanol 0.4 0.4
PO 0.4 0.4
Styrene 0.1 0.1
EEA 0.1 0.1
EE 0.1 0.1
EG 0.1 0.1
Final Gas State—Processed Above AIT
Fluid
Probability of
Ignition
Probabilities of Outcome
VCE Fireball Flash Fire Jet Fire Pool Fire
C1-C2 0.2 0.04 0.01 0.15
C3-C4 0.1 0.02 0.01 0.07
C5 0.1 0.02 0.01 0.07
C6-C8 0.1 0.02 0.01 0.07
C9-C12 0.04 0.01 0.005 0.025
C13-C16
C17-C25
C25+
H2 0.9 0.4 0.1 0.4
H2S 0.9 0.4 0.1 0.4
CO 0.899 0.4 0.099 0.4
DEE 0.899 0.4 0.099 0.4
Methanol 0.4 0.099 0.038 0.263
PO 0.4 0.178 0.044 0.178
Styrene 0.101 0.025 0.01 0.066
EEA 0.101 0.01 0.066 0.025
EE 0.101 0.01 0.066 0.025
EG 0.101 0.01 0.066 0.025
EO 0.9 0.4 0.1 0.4
NOTE 1 Shaded areas represent outcomes that are not possible.
NOTE 2 Must be processed at least 27 °C (80 °F) above AIT.