Environmental Bowtie Risk Analysis
Marine Bowtie Risk Analysis
Environmental risk assessment using the bowtie method — linking human activities to ecological consequences.
Getting Started
Load your own bowtie dataset from Excel or CSV.
Choose a built-in scenario and load it instantly.
Build a bowtie step-by-step with the wizard.
⬇ Download Results
Train the Random Forest on current data, then score all pathway links.
Which n-grams drive the ML link scorer's decisions.
Guided Workflow — 9 Steps
- Define Scope — Identify the activity / system under review.
- Identify Hazard / Central Problem — The top event in the bowtie.
- Left Side — Threats / Pressures — List causal pathways leading to the hazard.
- Preventive Controls — Barriers on the left that reduce likelihood.
- Right Side — Consequences — Outcomes if the hazard materialises.
- Mitigating Controls — Barriers on the right that reduce severity.
- Risk Scoring — Assign Likelihood (1–5) and Severity (1–5) per pathway.
- Bayesian Network — Encode uncertainty as conditional probability tables.
- Review & Export — Validate, generate reports, and share with stakeholders.
Risk Matrix
Likelihood and Severity are each scored on a 1–5 scale.
| Score | Likelihood | Severity |
|---|---|---|
| 1 | Rare | Negligible |
| 2 | Unlikely | Minor |
| 3 | Possible | Moderate |
| 4 | Likely | Major |
| 5 | Almost Certain | Catastrophic |
Risk Score = Likelihood × Severity (1–25).
Thresholds: Low ≤ 6, Medium 7–15, High ≥ 16.
Bayesian Networks
A Directed Acyclic Graph (DAG) where nodes are random variables (Activity, Pressure, Central Problem, Consequence) and edges represent causal dependencies.
Inference propagates evidence through the network to update posterior probabilities using Variable Elimination or Belief Propagation.
This app uses pgmpy for structure learning and inference.
BowTie Methodology
The BowTie diagram is a visual risk assessment tool combining:
- Fault Tree Analysis (FTA) on the left (threats → top event)
- Event Tree Analysis (ETA) on the right (top event → consequences)
Originally developed by the oil & gas industry, it is now widely used in environmental, health, and safety management.
Getting Started
- Upload your Excel/CSV data using the Data Upload tab, or generate sample data via the sidebar Scenario picker.
- Select a Central Problem from the sidebar dropdown.
- Explore the Bowtie Diagram, Risk Matrix, and Bayesian Networks tabs.
- Use Guided Creation to build a new bowtie step by step.
- Export results from the Reports tab.
FAQ
Q: What file format is expected?
A: An Excel or CSV file with at minimum columns: Activity, Pressure,
Central_Problem, Consequence, Likelihood, Severity.
Q: Can I add custom vocabulary?
A: Yes — use the Vocabulary tab to add project-specific terms.
Environmental Bowtie Risk Analysis Tool
Version 0.6.0 - developed within the MARBEFES Horizon Europe project.
The content below is rendered from the project README and CHANGELOG.