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Root Cause Categories

The CSB categorises failures at two levels: the immediate physical cause (what broke) and the underlying systemic factors (why it was allowed to break). The categories below map to the systemic failure modes the CSB identifies across investigations — the conditions that made the physical failure possible and prevented safeguards from stopping escalation.

Each page lists every CSB investigation where that failure mode was cited, with incident details and data-derived patterns.

Root Cause / Failure Mode Investigations Top Industries
Procedural Failure 107 Chemical Manufacturing, Petroleum Refining
Design Deficiency 103 Chemical Manufacturing, Petroleum Refining
Training Deficiency 73 Chemical Manufacturing, Metals
Management of Change Failure 56 Chemical Manufacturing, Petroleum Refining
Communication Failure 49 Chemical Manufacturing, Petroleum Refining
Human / Operator Error 46 Chemical Manufacturing, Petroleum Refining
Emergency Response Failure 40 Chemical Manufacturing, Petroleum Refining
Maintenance Error 38 Chemical Manufacturing, Metals
Inspection Failure 35 Chemical Manufacturing, Petroleum Refining
Ignition Source Control Failure 26 Chemical Manufacturing, Transportation
Contractor Management Failure 25 Chemical Manufacturing, Oil And Gas Production
Alarm Management Failure 19 Chemical Manufacturing, Petroleum Refining
Relief System Failure 18 Chemical Manufacturing, Food Processing
Instrumentation Failure 15 Chemical Manufacturing, Petroleum Refining
Corrosion 15 Chemical Manufacturing, Petroleum Refining
Housekeeping Failure 10 Metals, Chemical Manufacturing
Control System Failure 7 Food Processing, Chemical Manufacturing
Overfill 4 Petroleum Refining, Wastewater Treatment

!!! tip "Use the Knowledge Graph for cross-filtering" The Knowledge Graph Explorer lets you combine filters — industry sector, hazard type, year range, and fatality count — to find incidents most relevant to your facility's context.


Data sourced from CSB.gov public investigation reports. This site is an independent project not affiliated with the U.S. CSB.