What is Tripod Beta?
Tripod Beta is an incident-investigation methodology developed by Shell that traces causation through agent–hazard–target trios, identifies failed barriers, and groups latent failures into eleven General Failure Types.
Born from Shell's research into major hazard incidents in the 1990s, Tripod Beta moved investigations beyond linear root-cause thinking. It treats every incident as the convergence of an active failure, situational preconditions and underlying organisational weaknesses — making it the gold standard for high-hazard industries like oil & gas, mining and chemicals.
How it works
1. Capture the narrative
Collect first-hand witness statements, control-room logs, CCTV and timestamps. The narrative becomes the source of truth for every downstream artefact.
2. Identify the Top Event and HET trios
Pinpoint the loss of control. Decompose every contributing thread into agent–hazard–target trios.
3. Map barriers and classify failures
For each trio, list every preventive and recovery barrier. Mark each barrier intact, failed or missing.
4. Trace immediate causes and preconditions
For every failed barrier, identify the unsafe act or condition (immediate cause) and the situational factors that enabled it.
5. Surface latent failures via GFTs
Classify each precondition under one of the eleven General Failure Types to expose the organisational weaknesses that must change.
6. Generate prioritised recommendations
Produce specific, measurable, time-bound recommendations targeting the most critical latent failures — and track them to closure.