Identifying Causes of Accidents Surface vs. Root Causes Surface causes are: the hazardous conditions or unsafe work practices that directly or indirectly contributed to the accident. Root causes are: the safety or loss control system weaknesses that allow the existence of hazardous conditions and unsafe work practices. Most accident investigations only identify the surface causes of accidents.

Events and Causal Factor Analysis Events and Causal Factor Analysis identifies the time sequence of a series of tasks and/or actions and the surrounding conditions leading to an occurrence. The results are displayed in an Events and Causal Factor chart that gives a picture of the relationships of the events and causal factors.

Change Analysis Change Analysis is used when the problem is obscure. It is a systematic process that is generally used for a single occurrence and focuses on elements that have changed.

Barrier Analysis Barrier Analysis is a systematic process that can be used to identify physical, administrative, and procedural barriers or controls that should have prevented the occurrence.

Management oversight and Risk Tree (MORT) Analysis MORT and Mini-MORT are used to identify inadequacies in barriers/controls, specific barrier and support functions, and management functions. It identifies specific factors relating to an occurrence and identifies the management factors that permitted these factors to exist.

Human Performance Evaluation Human Performance Evaluation identifies those factors that influence task performance. The focus of this analysis method is on operability, work environment, and management factors. Man-machine interface studies to improve performance take precedence over disciplinary measures.

Kepner-Tregoe Problem Solving and Decision Making Kepner-Tregoe is a management consulting firm Kepner-Tregoe provides a systematic framework for gathering, organizing, and evaluating information and applies to all phases of the occurrence investigation process. Phases: Situation appraisal: Identify concerns Problem analysis: Define the problem (Similar to Change Analysis) Decision Analysis: Evaluate alternatives, assess risks Potential Problem Analysis: What new problems may be introduced by the alternatives?

Accident Investigation Process The accident investigation process involves the following steps: Report the accident occurrence to a designated person within the organization Provide first aid and medical care to injured person(s) and prevent further injuries or damage Investigate the accident Identify the causes Report the findings Develop a plan for corrective action Implement the plan Evaluate the effectiveness of the corrective action Make changes for continuous improvement

Retrospective Investigations Retrospective investigations are accident investigations that look back in time at a situation. Most investigations conducted in the workplace can be classified as a retrospective investigation.

Statistical Investigations Statistical investigations utilize data collected over a period of time to determine causes and develop prevention measures. Statistical investigations utilize mathematical techniques that identify the causes for accidents in terms of statistical probabilities.

Large Loss Investigations Large loss investigations are considered in-depth investigations directed at an accident that resulted in a larger than usual loss of life, money, or property damage. Examples of large loss investigations include large industrial fires, plant explosions, and airplane crashes

Systems Investigations Systems investigations utilize a systems approach to the identification of causal factors. There are a variety of systems investigation techniques available including root cause analysis, Fault Tree Analysis (FTA), and Failure Modes and Effects analysis (FMEA).