Loss of containment — storage tank
The classic process-safety bowtie: corrosion, overfill, ignition sources and impact around an atmospheric hydrocarbon tank.
5 threats 19 barriers 4 consequences safety-critical barriers marked
Use this template free. Copy “Loss of containment — storage tank” into your own workspace and adapt every barrier — no credit card.
Start free with this template →Threats & preventive barriers
Each threat is a credible pathway to the top event; its barriers interrupt that pathway before control is lost.
Corrosion of tank shell
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Risk-based inspection programme
Socio-technical · 80% effective · Owner: Integrity Engineer
📅 Wall-thickness survey · quarterly keep-alive task
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Corrosion coupons & monitoring
Continuous · 85% effective · Owner: Integrity Engineer
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Cathodic protection system
Passive (hardware) · 80% effective · Owner: Corrosion Engineer
Overfilling during transfer
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Independent high-level alarm
Socio-technical · 80% effective · Owner: Control Room Supervisor
Alarm flooding
Operator fatigue on night shift
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High-high level auto-shutdown (SIF) ★ critical
Active hardware · 95% effective · Owner: Instrument Reliability Engineer
📅 Proof test (full stroke) · semiannual keep-alive task
External impact (vehicle strike)
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Crash barriers & bollards
Passive (hardware) · 90% effective · Owner: Site HSE Manager
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Traffic management plan
Behavioural (human) · 70% effective · Owner: Logistics Coordinator
Internal overpressure
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Pressure/vacuum relief valve ★ critical
Passive (hardware) · 88% effective · Owner: Mechanical Engineer
📅 PV valve inspection · annual keep-alive task
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Nitrogen blanketing control
Active hardware · 80% effective · Owner: Process Engineer
Static discharge during filling
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Bonding & earthing of fill lines
Passive (hardware) · 85% effective · Owner: Operations Lead
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Reduced initial fill rate
Behavioural (human) · 70% effective · Owner: Operations Lead
Consequences & recovery barriers
Once the top event happens, recovery barriers limit each consequence.
Pool fire
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Fire & gas detection
Active hardware · 80% effective · Owner: Instrument Reliability Engineer
📅 Detector calibration · quarterly keep-alive task
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Foam deluge fire suppression ★ critical
Active hardware · 90% effective · Owner: Fire Officer
📅 Flow & functional test · annual keep-alive task
Spill to watercourse
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Bund / secondary containment ★ critical
Passive (hardware) · 95% effective · Owner: Site HSE Manager
📅 Bund integrity inspection · annual keep-alive task
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Interceptor & drainage isolation
Socio-technical · 80% effective · Owner: Environmental Lead
Toxic vapour cloud
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Perimeter gas detection & alarms
Active hardware · 70% effective · Owner: Instrument Reliability Engineer
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Emergency response & evacuation plan
Behavioural (human) · 75% effective · Owner: Emergency Coordinator
📅 Evacuation drill · semiannual keep-alive task
Escalation to adjacent tanks
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Tank spacing & fire walls ★ critical
Passive (hardware) · 85% effective · Owner: Engineering Manager
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Water-spray cooling on neighbours
Active hardware · 80% effective · Owner: Fire Officer
Copying this template gives you a fully editable bowtie: barrier owners arrive as role suggestions, escalation factors sit on their barriers, and keep-alive activities are scheduled from the moment you copy. New to the notation? Read what the bowtie method is or browse the practical guides.
Use this template free. Copy “Loss of containment — storage tank” into your own workspace and adapt every barrier — no credit card.
Start free with this template →