Heinrich Pyramid Explained: 3 Levels of Precursor Evidence
Heinrich's pyramid is useful when leaders read minor events and near misses as precursor evidence, not as a promise that serious harm will follow.
Workplace safety, leadership and risk insights from the Headline Podcast editorial team.
Por Andreza Araujo Host & Editorial Lead
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Heinrich's pyramid is useful when leaders read minor events and near misses as precursor evidence, not as a promise that serious harm will follow.
Near misses are useful only when investigations reconstruct the exposure, test the barriers, preserve different accounts, and assign actions that change the work. Five evidence gaps can turn a warning into a reassuring story.
Lac-Megantic shows why a familiar securement routine can become a major safety failure when the organization does not verify the barrier, challenge assumptions, and assign ownership for unresolved risk.
The Flixborough explosion shows how a temporary process modification can become a major-hazard decision when technical review, operating limits, and leadership ownership do not keep pace with the changed configuration.
Deepwater Horizon was not a single technical mistake. It was a chain of warning signals that did not change the decision, because contractors, engineers, supervisors, and leaders did not share one escalation standard for a high-consequence well-control risk.
Incident reviews often fail before the formal report is written. Warning evidence is filtered by classification, hindsight, incomplete interviews, weak barrier analysis, and corrective actions that close on paper while exposure remains. This diagnostic shows leaders how to preserve the signal that serious-risk investigations need.
An event timeline, a causal map, and a barrier review answer different investigation questions. Match the method to the evidence so the final report changes a control instead of merely describing an incident.
Evidence contamination begins when the incident record changes before investigators have preserved what was observed, measured, or said. This glossary explains four moments where contamination enters, how to distinguish a damaged record from an incomplete one, and what leaders can do to protect findings without turning the review into a blame exercise.
The 1976 Seveso accident changed major-hazard safety by moving accountability beyond the plant boundary. This incident-investigation case explains how prevention, emergency planning, public information, and inspection became one governance system.
Tim Page-Bottorff's Headline Podcast conversation offers a precise test for incident reviews. Ask what conditions produced the event, rather than who can be made responsible for it, then turn the answer into an owned and verified change in the work.