SECTION A2: ACCIDENT INVESTIGATION
Accidents occur when hazards escape detection during preventive measures,
such as a job or process safety analysis, when hazards are not obvious,
or as the result of combinations of circumstances that were difficult
to foresee. A thorough accident investigation may identify previously
overlooked physical, environmental, adminstrative, or process hazards, the need for
new or more extensive safety training, or unsafe work practices. The
primary focus of any accident investigation should be the determination
of the facts surrounding the incident and the lessons that can be learned
to prevent future similar occurrences.
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Scope and Application
All accidents should be investigated. The depth and complexity of the
investigation will vary with the circumstances and seriousness of the
accident. The Supervisor or other individual responsible for operations
involved in an accident should ensure that an investigation is conducted
and that when appropriate, corrective actions are taken.
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The first priority whenever an accident occurs is to deal with the
emergency and ensure that any injuries or illnesses receive prompt
attention. The accident investigation should begin immediately thereafter.
This ensures that details of what occurred will be fresh in peopleís
minds and that witnesses donít influence one another by talking about
the accident. It also minimizes the likelihood that important evidence
is not moved, lost, taken, destroyed, or thrown away before the scene
has been thoroughly inspected.
Types of Accidents
Accidents fall into two categories, serious and non-serious. Non-serious
accidents do not cause lost workdays even though the worst that could
happen did happen. Examples of these include paper cuts, minor scratches
or abrasions, or system failures that have minor consequences, such
as a low-pressure hose that ruptures and sprays cool water. Serious
accidents include both those which did involve lost workdays and those
which might have. This second type of serious accident is called a
"near miss." Examples of near misses with serious injury potential
- A worker twists an ankle in a fall from a low scaffold (this
could easily have been a broken leg or worse);
- A worker tips back in a chair and topples backward (backward
falls are always serious because head injury might result);
- A worker turns on a machine and gets a slight shock (shock from
voltage potential greater than 75 volts DC or 40 volts AC is considered
After an accident or near miss occurs, supervisors should contact EHS. All serious accidents, those
involving lost workdays or near misses, should be investigated with
the same thoroughness.
Who Should Investigate
Supervisors should note initial details of the incident and contact EHS to schedule an interview with the injured employee. Regardless of the type of investigation, the supervisor should be
involved for the following reasons:
- Supervisors have a responsibility to provide their workers with
a safe and healthful workplace;
- Supervisors know the workers and their work better than anyone
else and are in the best position to gather the facts and find a
practical solution to the problem;
- The supervisorís involvement can help promote better
relations with workers by demonstrating concern for their safety
and attention to accident prevention.
Accident Investigate Approach
As with most other tasks, skill in conducting effective accident
investigations improves with experience. A good basic approach is
to find out what caused the accident and what can be done to prevent
or minimize the chances of a similar accident occurring. Some suggestions
that may help supervisors get the facts and reach a conclusion include:
- Maintain objectivity throughout the investigation. Its purpose
is to find the cause of the accident, not to assign blame for its
- Check the accident site and circumstances thoroughly before anything
- Discuss the accident with the injured person, but only after
first aid or medical treatment has been given (see Section
A1, Work-Related Injuries and Illnesses). Also talk with
anyone who witnessed the accident and those familiar with conditions
immediately before and after it occurred.
- Be thorough. Small details may point to the real cause.
- Reconstruct the events that resulted in the accident, considering
all possible causes. Determine unsafe conditions or actions that
separately or in combination were contributing factors.
What To Do With The Results
Supervisors should take action to control or eliminate the conditions
that caused the accident once these have been conclusively identified.
EHS can provide assistance in determining the level of action that
may be necessary, such as the following:
- When equipment changes or safeguards are necessary, supervisors
should discuss specific recommendations with Department management;
- When an operation can be changed to eliminate the hazard, supervisors
should make the change if it is within their authority, or seek
the necessary approval from Department management;
- If unsafe acts by workers are involved, ensure that the worker
is properly trained and that training is followed. All others involved
in similar operations should be trained as well.
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Roles and Responsibilities
- Ensure accidents involving their operations or workers are investigated.
- Ensure corrective actions are taken.
- Particpate in incident investigations.
- Take corrective actions.
- Investigate incidents promptly and thoroughly.
- Issue accident investigation reports.
- Provide training in investigation methods and techniques when requested.
- Cooperate with supervisors and others during investigations.
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For More Information
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