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The Ultimate Accident Investigator’s Guide

Copyright © 2016 Geigle Safety Group, Inc. All rights reserved. Published in the United States of
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ISBN 978-0-9971617-0-0

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permission in writing from Geigle Safety Group, Inc.

Permission may be obtained by contacting:

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Disclaimer

This document does not constitute legal advice. Consult with your own company counsel for advice on compliance with all applicable state and
federal regulations. Neither Geigle Safety Group, Inc., nor any of its employees, subcontractors, consultants, committees, or other assignees
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compliance regulatory requirements.
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CONTENTS
Introduction .................................................................................................................................................. 1

Phase One: Gather the Facts ........................................................................................................................ 6

Step 1. Secure the Accident Scene (if required) ....................................................................................... 6

Step 2. Collect Pertinent Information ....................................................................................................... 6

Phase Two: Analyze the Facts ..................................................................................................................... 11

Step 3. Develop the Sequence of Events ................................................................................................ 11

Step 4. Uncover the Surface and Root Causes ....................................................................................... 12

Phase Three: Report the Facts .................................................................................................................... 22

Step 5. Recommend Corrective Actions and Program Improvements ................................................... 22

Step 6. Write the Report......................................................................................................................... 25

References .................................................................................................................................................. 27

Appendices .................................................................................................................................................. 28

Appendix 1. Accident Types – Event or Exposure Leading to Injury ...................................................... 28

Appendix 2. Forms of Energy Causing Injury .......................................................................................... 29

Appendix 3. Types of Hazards................................................................................................................. 30

Appendix 4. Surface Causes .................................................................................................................... 34

Appendix 5. Root Causes ........................................................................................................................ 40

Appendix 6. Sketching Techniques ......................................................................................................... 44

Appendix 7. Sample Accident Investigation Witness Statement ........................................................... 45

Appendix 8. Sample Interview Questions............................................................................................... 48

Appendix 9. Sample Sequence of Events................................................................................................ 53

Appendix 10. Sample Accident Investigation Report Form .................................................................... 54

Supplemental Materials .............................................................................................................................. 58

Supplement 1. Safety Management Systems ......................................................................................... 58

Supplement 2. Sample Accident Analysis Team Kit ................................................................................ 59

Supplement 3. Photographic Evidence—General .................................................................................. 59

Supplement 4. “Fix the System” Incident/Accident Analysis Plan ......................................................... 61

A. General Policy ................................................................................................................................ 61

B. Incident/Accident Reporting .......................................................................................................... 61

C. Pre-planning ................................................................................................................................... 61

D. Incident/Accident Analysis............................................................................................................. 62

E. Management Responsibilities ........................................................................................................ 62

F. Incident/Accident Analysis Team ................................................................................................... 62

G. Determining the Facts.................................................................................................................... 63

H. Determining the Cause .................................................................................................................. 64

I. Recommending Corrective Actions and System Improvements ..................................................... 65

J. Follow-up System ............................................................................................................................ 65

K. Communicating Results .................................................................................................................. 65

L. Review and Approval ...................................................................................................................... 66

OSHAcademy The Ultimate Accident Investigator’s Guide

INTRODUCTION
Why Conduct an Accident Investigation?
As an accident investigator, it is important to know from the start that the purpose of the investigation
is to prevent recurrence. Accident investigations prevent recurrence by helping you achieve the
following:

1. Find out what happened.

2. Uncover surface cause conditions and behaviors.
3. Uncover the underlying root causes.
4. Implement corrective actions.
5. Implement safety program improvements.

Uncover surface Uncover the

Find out what
cause conditions underlying root
happened
and behaviors causes

Implement Implement
corrective safety program
actions improvements

Fix the System, Not the Blame

As you can see above, the purpose of the investigation is to ultimately correct conditions and behaviors
and to improve safety program, policies, processes, plans, procedures, work instructions, rules, and
guidelines.

The report should not state who is to blame.

As the investigator, you should not do or say anything that implies you are trying to place blame on the
injured employee or others. Why? If the purpose of the investigation is to establish fault, then when

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enough data is obtained to establish fault (usually that does not take long), the process stops, and
analysis of the safety management system (SMS) does not occur.

Placing blame and discipline are not appropriate unless the employee violated stated safety policies or
rules and the safety management system did not contribute to that behavior. You will not have enough
information to accurately determine fault until the accident investigation that includes SMS evaluation
has been completed. If you discover root causes that contributed to the accident, forget about
discipline: It won’t be justified. If you and the Safety Department can’t find root causes that contributed
to the condition/behaviors that caused the accident, then there may be justification for discipline and
that determination is made by conducting a personal performance appraisal of the specific behavior: A
completely different process.

The error made by the employee may not be even the most important contributing cause. The
employee who has not followed prescribed procedures may have been encouraged directly or indirectly
by a supervisor or production quotas to "cut corners." The prescribed procedures may not be practical,
or even safe, in the eyes of the employee(s). Sometimes where elaborate and difficult procedures are
required, engineering redesign might be a better answer. In such cases, management errors -- not
employee error -- may be the most important contributing causes. Even if injured workers openly blame
themselves for making a mistake or not following prescribed procedures, you must not be satisfied that
all contributing causes have been identified.

“CONDEMNATION WITHOUT INVESTIGATION IS THE HEIGHT

OF IGNORANCE.” ALBERT EINSTEIN

Accident investigators must describe causes carefully and clearly. When reviewing accident investigation
reports, the Safety Department should be on the lookout for catch-phrases, for example, "Employee did
not plan job properly." While such a statement may suggest an underlying problem with this worker, it is
not conducive to identifying all possible causes, preventions, and controls. Certainly, it is too late to plan

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a job when the employee is about to do it. Further, it is unlikely safe work will always result when each
employee is expected to plan procedures alone.

WHEN THE PURPOSE OF THE INVESTIGATION IS ACHIEVED, IT STOPS

Accident investigations that primarily attempt to fix the blame stop once the investigator believes the
fault has been established. Such investigations will make some kind of claim that the victim:

was lazy
lacked common sense
was careless
should have known better
was dumb or stupid
was inattentive
was accident-prone
had a poor attitude

The investigator who quickly arrives at these "causes" for an accident is committing an attribution error.
The investigator mistakenly attributes a performance failure to personal causes before considering
external factors that may be contributing to the behavior.

Investigations that take this “Band-Aid” approach by merely fixing blame rarely analyze and evaluate
safety programs. Consequently, similar accidents occur repeatedly.

When Do You Conduct an Investigation?

All accidents, no matter how minor, should be investigated. Near-miss investigation allows you to
identify and control hazards before they cause a more serious accident. The injury/accident
investigation is a tool for uncovering hazards that either were missed earlier or have managed to slip out
of the controls planned for them. It is useful only when done with the aim of discovering every
contributing factor to the accident to "foolproof" the condition and/or activity and prevent future
occurrences.

Who Should Investigate?

Usually, the accident investigator is the supervisor in charge of the involved area and/or activity.
Investigations represent a good way to involve employees in safety and health. Employee involvement
will not only give you additional expertise and insight, but, in the eyes of the workers, will lend
credibility to the results. Employee involvement also benefits the involved employees by educating them
about potential hazards, and the experience usually makes them believers in the importance of safety,

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thus strengthening the safety culture of the organization. The Safety Committee may participate in the
investigation or review the investigative findings and recommendations involving serious injury or
extensive property damage.

Implications of Accident Investigations

Recommended preventive actions should make it very difficult, if not impossible, for the accident to
reoccur. The investigative report should list all the ways to "foolproof" the condition or activity.
Considerations of cost or engineering should not enter at this stage. The primary purpose of accident
investigations is to prevent future occurrences. Beyond this immediate purpose, the information
obtained through the investigation should be used to update and revise the inventory of hazards, and/or
the program for hazard prevention and control. For example, the Job Safety Analysis should be revised
and employees retrained to the extent that it fully reflects the recommendations made by an accident
report. Implications from the root causes of the accident need to be analyzed for their impact on all
other operations and procedures.

BENEFITS OF THE INVESTIGATION

Ted S. Ferry, a well-recognized expert in accident analysis and author of Modern Accident Investigation
and Analysis, lists a number of objectives of accident investigation (included below). We should also
think of these objectives as benefits of effective accident investigation. The list could be greatly
expanded. The rationale for each objective is usually self-evident.

Reduce danger to employees. Provide protection against litigation.

Prevent company resource loss. Satisfy insurance requirements.
Prevent further mishaps. Improve company products.
Respond to management needs. Educate supervisors and managers.
Prevent loss of trained personnel. Develop cost information.
Develop costing information. Anticipate government interest.
Improve operating efficiency. Identify errors in procedures.
Provide answers to public concern. Comply with workers’ compensation.
Define operating errors. Satisfy regulatory requirements.
Define management errors. Improve quality control and reliability.
Satisfy company rules. Isolate design deficiencies.
Reduce work process disruption. Satisfy news media.

The order of listing is not important. Commonly voiced objectives that lack sound reasoning are not
included. Samples of those are (1) do it for the sake of appearances, (2) justify safety manager’s job, and
(3) “hang someone to set an example.”

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Investigating to determine liability is quite different from the objective of defining management errors.
While it may seem that one good investigation would serve all purposes, for legal reasons and practical
expenditure of resources, this is not feasible. It is true the more complete and in-depth an investigation
is, the more likely it is to serve more objectives. However, it is not practical to investigate each minor
injury or mishap as if the survival of the organization depended on it. (Source: Modern Accident
Investigation and Analysis, Ted S. Ferry, p.4)

Steps to Conducting an Accident Investigation

There are three phases and six steps to conducting an accident investigation:

a. Phase One: Gather the Facts

1. Secure the Accident Scene (if required)
2. Collect Pertinent Information
b. Phase Two: Analyze the Facts
3. Develop the Sequence of Events
4. Uncover the Surface and Root Causes
c. Phase Three: Report the Facts
5. Recommend Corrective Actions and Program Improvement
6. Write the Report

These will be discussed in the following sections.

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PHASE ONE: GATHER THE FACTS

Step 1. Secure the Accident Scene (if required)
The first step in a serious injury accident investigation is to secure the accident scene. This is very
important if OSHA also investigates the accident. Secure the scene so you can have time to make
sketches, take photos, take measurements and obtain other necessary information. To secure the
accident scene, use yellow caution tape or warning cones. If the accident occurs in the tower, nacelle, or
hub, it may not be safe or feasible to secure the scene.

Step 2. Collect Pertinent Information

In this step, you will use various tools and techniques to collect pertinent facts about the accident. The
information you gather in this step will be used to determine the:

Cause of Injury. You will want to know what caused the injury or illness (See Appendix 1 for a
list of accident types). An injury occurs immediately while an illness occurs over time. Both injury
and illness are caused by the harmful transfer of energy. Harmful forms of energy transfer can
include chemical, thermal, mechanical (See Appendix 2) and can result in several different types
of hazards. (See Appendix 3)
Surface Causes. Hazardous conditions and behaviors that produced or contributed to the
accident. (See Appendix 4)
Root Causes. Underlying safety program weaknesses that contributed to the surface causes for
the accident. (See Appendix 5)

CATEGORIES OF INFORMATION
There are four categories of information that will provide facts about the accident:

Physical Evidence. Collect facts about the tools, equipment, machinery, facilities, and
environment that caused or somehow contributed to the accident. Note the position and
condition of physical evidence. What is present or absent? What are the environmental
conditions at the scene? Record what you see and don’t see.
Paper Evidence. Examine written documentation, such as policies, procedures, work
instructions, training records, maintenance records, previous accident records, HSE alerts and
bulletins, risk assessments, job hazard analyses and tailgate/safety meetings records.
People Evidence. To gather people evidence, make sure you get written eye/ear witness
information. Conduct interviews with all parties, such as the victim(s), co-workers, supervisors,
maintenance workers, and trainers.

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Picture Evidence. Take photos of material evidence where it is. Also, take photos of the accident
scene starting with far-away shots and moving in close. Number each photo and label it with the
orientation of the shot (N,E,S,W) and the object being viewed. Draw a sketch of material
evidence and the accident scene. Sketches are very useful because you can show motion
through time, the precise position of material evidence, and include a lot of other information.
(See Appendix 6 for information regarding sketching techniques).

It is a good idea to obtain written statements from witnesses. Written statements can be quite valuable
in writing follow-up questions for interviews. To ensure candor while making statements, witnesses
should be isolated from each other when making their individual statements. Inform witnesses that
their written statements, although shared, will be used for accident prevention purposes only. Make
sure witnesses thoroughly describe the “who, what, where, when, how” related to what they saw and
heard. Always ask the question, “What did you see and hear?”

Use a Sample Accident Investigation Witness Statement Form (see Appendix 7) or create your own
variation that answers the following questions:

Name, work address, and phone number

Workstation (location) and position (job title)
Description of what happened. Begin when you first noticed something
Technical background, skills, or knowledge
Connection or working association with those involved in the accident
Time of the accident
What attracted your attention to the accident
The position of the vehicle or equipment and individual involved in the accident when first seen
The direction of travel, fall, or final resting place of the vehicle or equipment and individual
involved in the accident (draw a diagram, if appropriate.)
The weather at the time of the accident (Was it clear and sunny? Was it rainy or smoky? What
were the wind conditions, e.g., velocity, gusty?)
Actions taken at the accident site
Other eyewitnesses around
Any additional information you would like to provide

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After the site visit, interview the “eye-ear witnesses” and others. Eyewitnesses may be your best or only
source of information for determining the accident sequence of events. It is important to interview as
soon as possible.

The mental state of the witnesses in regards to critical accident stress should be taken into account.
They may be in shock or traumatized following the accident. They may also be on medication and
require the approval of the attending physician before making statements or being interviewed. On the
other hand, they are frequently anxious to talk about the accident to anyone who will listen. Providing
them with an opportunity to talk about the events surrounding the accident may be helpful to their
psychological recovery.

You will want to interview the victim, if possible, co-workers, supervisors, maintenance personnel,
trainers, and others who might have some relationship to the accident.

Interviews need to be conducted in quiet, private, comfortable locations that are free of disruption.
Provide frequent breaks. Depending on the amount of information needed, an interview may need to be
divided up and held in subsequent sessions. Most likely, after you’ve developed the sequence of events
in Step 3 of Phase 3, you’ll need to contact witnesses to ask follow-up questions.

Questioning the Interviewee

Control questions should be developed and used. Control questions provide consistency and ensure that
pertinent information is collected in all interviews. Always ask the following basic questions during the
interview:

What did you see and hear?

Can you tell me more about that?
What you think might have caused the accident?
How can we prevent this accident in the future?

Asking the above questions will generate more questions. Don’t forget to ask follow-up “why”
questions. For instance, let’s say you ask, “How long had the victim been working that day?” The
employee thinks for a moment and responds, “Twelve hours.” As a follow-up question, you might ask,
“Why had the victim been working for 12 hours?” However, be careful when asking “why-you”
questions, as they may be perceived as accusatory. (See Appendix 8 for more question examples.)

Ensure the name, work address, phone number, date, and name of the interviewee are included in the
interview document. In some instances, witnesses may have to be taken to the accident site after the
initial interview for clarification of their statement.

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There should be no objection if an employee would like a co-worker, supervisor, or other person
included in the interview. Anything you can do to help the interviewee be comfortable providing facts is
appropriate. Never send any kind of message you are attempting to conceal information.

The idea of questioning is to get the interviewee to tell you everything he/she knows without being
influenced by either the question or by what he/she thinks you want to hear. Usually, it is advantageous
to move from general to specific questions and from the known to the unknown.

The interview begins by thanking the interviewee for participating in the interview, telling the
interviewee why the process is important, reviewing name, work address, and phone number, position
(job title), and his/her location during the accident for accuracy.

The best approach is first to ask the person to explain, in his or her own words, what happened. Ask
them to start when they first noticed something. This usually helps put the person at ease and gives you
a pretty good idea of what they know.

Interview Do’s
Be sure to follow the recommendations below when performing an accident investigation interview:

Read the witness’ written statement (if available) before the interview. Develop questions from
the statement.
Explain who you are and what you are doing.
Be sensitive to the emotional state of the individual. Allow witnesses to tell the story in their
own words (do not interrupt).
Distinguish “thoughts” from “feelings.” They are not the same. Ask for both. Thoughts reflect
ideas. Feelings describe how the person felt about something.
Tell the interviewee why he or she is being interviewed. Tell them why it’s important to get at
the facts and that they can be a great help in that effort.
Explain you need his or her help to understand, as accurately as possible, what happened.
Emphasize open-ended questioning and requests rather than closed “yes-no” response
questions.
The most important question "and then what happened?"
Asking “why” questions, such as, “Why did the equipment stop working?” is fine. Use the “5-
whys” technique discussed in the Uncovering Root Causes section in this guide. Keep asking why
to each response. This technique can help you uncover root causes.
Take notes and, when finished, let the interviewee read, add information, and sign or initial that
the notes are accurate.

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When possible "walk through" the actions of the individual. People recall things best in order of
occurrence.
Take your time. You are after quality as well as quantity of data.
Whenever possible, limit team members participating in the interview to two members.
Remember, you are trying to create a mental movie.

Interview Do Not’s
When performing an accident investigation interview, never forget the following:

Resist asking “why-you” questions, such as, “Why did you fail to reset the switch?” Doing so may
cause the interviewee to think you are accusatory. If that happens, the interviewee will become
defensive or suspect you are really searching to find fault.
If the interviewee appears defensive, it may indicate they perceive what you’ve said or your
tone of voice as accusatory, belittling or otherwise blaming. Apologize if needed and rephrase
the question.
Do not come across as trying to establish truth from lies. Most of the time, people will tell you
the truth. If you come across as judgmental or accusatory, the interviewee will be more likely to
be untruthful in some way.
Do not prejudge a witness. Keep an open mind so you can be receptive to all information,
regardless of its nature. Be serious. Maintain control of the interview. Don’t make promises you
can’t keep. Avoid contemptuous attitudes. Avoid controversial matters. Respect the emotional
state of the witness.
Avoid collective interviews (interviewing more than one witness at a time). Be a good listener.
Be unobtrusive when taking notes. Maintain your self-control during interviews. Don’t become
emotionally involved in the investigation.
Do not assist the witness in answering questions.
Avoid revealing items discovered during the investigation to the witness.

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PHASE TWO: ANALYZE THE FACTS

The second phase of the accident investigation begins the actual analysis process. In this phase, you will
organize and analyze the facts gathered during Phase One. To organize the facts, you’ll develop the
sequence of events that occurred prior to, during, and after the accident. To analyze the data, you’ll
examine each event to identify surface causes and then, by asking “why,” you’ll attempt to discover
underlying root causes.

Step 3. Develop the Sequence of Events

A near miss or injury is the final event in a series of events.

In this step, take the information you have gathered to determine the events prior to, during, and after
the near miss/injury accident. It’s important to note that a serious injury or accident can easily be the
result of 20 or more events. Events can occur anytime, anywhere, any place, and by anyone. It’s possible
that pertinent events may have occurred many weeks or months before the accident. There are four
categories of events:

1. Actual Events. These are events that you are able to determine actually occurred.
2. Assumed Events. These are events that must have happened but have not yet been verified.
Flag these somehow as a reminder that more investigation is needed.
3. Non-Events. Although these describe events that did not occur, they should be captured
because they may help discover conditions and behaviors relevant to the investigation.
4. Simultaneous Events. It is possible for two events to occur at the same time. Each event would
describe different actors and actions.

Developing the sequences of events that occurred prior the near miss or injury takes time, but it’s a
critical process for a number of reasons. Doing so makes it possible for you to do the following:

More accurately validate and verify the facts.

Discover holes in the accident sequence.
Eliminate the need to “memorize” what happened.
Write a more accurate report.
Uncover a greater number of surface and root causes.

Each event in an unplanned accident process identifies:

1. An “actor” – the person or thing that accomplishes an action. An actor initiates a change by
performing or failing to perform an action. An actor may participate in the process or merely
observe the process.

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2. An “action” – the behavior the actor accomplishes. Actions may or may not be observable. An
action may describe something that is done or not done.

CHARTING THE SEQUENCE OF EVENTS

Some experienced accident investigators develop the sequence of events using index cards taped to a
wall or table (See example below or Appendix 9). This will allow you to rearrange the sequence as facts
are learned.

The sequence of events represents a timeline of unique occurrences. Note that increasingly greater
negative integers are used to label events prior to the injury event. The injury/near miss event is labeled
as the “zero” event. Events occurring after the accident (0 event) are labeled with increasingly positive
integers.

Be sure you include only one actor and one action in each event. Don’t number events until you’re
finished developing the correct sequence of steps. To help develop the sequence, remember to ask,
"What happened next?" Put the source of the information on the back of the card.

-11
Event ____ Feb 2 - 1330
Event -10
____ Feb 2 - 1335 Event -8
____ Feb 2 - 1337
Bob gets the six-foot -9
Event ____ Feb 2 - 1336 -7
Event ____ Feb 2 - 1337
step ladder from Bob carries ladder to the Ralph tells Bob to hurry up
the storage room overhead light in the Bob notices oil on his because the filter on the air Bob grabs the florescent
in the warehouse. warehouse that needs workshoes and wipes it off conditioning needs light with his left hand and
replacement. with a rag. replacement. climbs the step ladder.

-6
Event ____ Feb 2 - 1337 -5
Event ____ Feb 2 - 1337 -4
Event ____ Feb 2 - 1338
-3
Event ____ Feb 2 - 1338 -2
Event ____ Feb 2 - 1338
Bob lays the florescent Bob positions his feet on As Bob reaches to remove
light across the top the fourth rung of the the defective florescent Bob is startled and quickly The right side of the fourth
platform of the ladder. ladder (second from top). light, the replacement bulb reaches to catch the rung of the ladder
begins to roll off the ladder moving bulb before it falls separates from the leg of
platform. to the floor. the ladder.

-1
Event ____ Feb 2 - 1338
0
Event ____ Feb 2 - 1338 Event +1
____ Feb 2 - 1338 Event +2
____ Feb 2 - 1338
Bob's right foot slips
through the space between Bob's left leg buckles and Ralph and Betty see Bob
the fourth and fifth rung of Ralph tells Betty to hold the
he falls back striking his falling and rush to help him
ladder and carefully lifts
the ladder. back and head against the before the ladder falls.
Bob and helps him out of
ladder. the ladder.

Step 4. Uncover the Surface and Root Causes

For every effect, there is a cause.

Now that developing the sequences of events is accomplished, the next step is to analyze each event to
see which contain conditions and behaviors that may have contributed to an accident. By continuing to

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ask “why” for each condition and behavior, you may eventually discover their underlying root causes for
those conditions and behaviors.

SURFACE AND ROOT CAUSES

The Surface Cause of the accident describes a unique, individual, or single hazardous workplace
condition or unsafe/inappropriate employee behavior that directly causes or contributes to
the accident. There are two types of surface causes: 1) surface cause conditions, and 2) surface cause
behaviors.

Surface cause conditions may include:

Unguarded machines
Uneducated employees
Slippery surfaces
Defective PPE

Surface cause behaviors may include:

Failing to replace a guard

Failing to attend training
Walking on a slippery surface
Unsafe lifting techniques
Failing to inspect PPE
Horseplay
Telling a worker to work fast

Each item listed should be a single condition or individual behavior. It is also important to note surface
causes can occur at anytime, anywhere in the workplace, and by any one person. There may be many
surface causes for a particular accident and elimination of the surface cause(s) leads to the short-term
elimination of the problem.

A Root Cause is generally defined as, "The most fundamental reason(s) for the failure or inefficiency of a
process." Examples of root causes are safety program design and performance weaknesses and
generally include missing or inadequate supervision, training, accountability, and resources. Remember
the four areas with the acronym “STAR.”

Supervision. Safety inspections are not consistently performed (an occupational safety and
health management system performance flaw/weakness). Hazard Identification and Control
policies, plans or procedures are not in place (an OHSMS design flaw/weakness).

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Training. Failure to conduct Lockout/Tagout training for employees. A non-existent Safety

Training Program.
Accountability. Management is not adequately administering discipline. Supervisors may be
ignoring safety infractions or, in some way, actually encouraging unsafe behaviors. Disciplinary
policies, procedures, rules, and guidelines are not in place.
Resources. Managers may not be providing supervisors and employees with the tools,
equipment, materials, machinery, time, workload, etc. needed to work safely. The purchasing
policy may include safety as well as price. Engineering may not be considering safety by design.

“Deep” root causes include a lack of planning, commitment, and leadership at the top levels of
management. Deep root causes result in OHSMS design flaws. Design root causes result in OHSMS
performance flaws. Performance root causes result in surface causes.

Elimination of the root cause leads to the long-term elimination of the defect or problem.

Root cause analysis by qualified persons should be part of every accident investigation and personal
performance evaluation.

The following diagram illustrates how root cause analysis occurs. The observable effect at the top
represents the thoughts, feelings, behaviors, and/or conditions that are directly involved in causing the
accident (the final effect). We must know what these immediate surface causes are so that we can, by
asking why, ultimately get to the root causes.

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Observable Effect
What is the unique symptom being observed?
1.Thought 2. Feeling 2. Behavior 3. Condition
Analyze Survey Effect
Why? Interview What?
Evaluate Inspect Cause

Contributing Surface Causes

What are the conditions and behaviors contributing to the problem?
1. Material 2. Equipment 3. Environment 4. Employees
Analyze Survey
Interview Effect
Why? What?
Evaluate Inspect
Audit Cause

System Performance Root Causes

Is the failure to fulfill employer obligations contributing to the problem?
1. Leadership 2. Resources 3. Enforcement 4. Supervision 5. Training
Analyze Effect
Inspect
Why? What?
Audit
Evaluate Cause

System Design "Deep" Root Causes

Are programs, policies, plans, processes, procedures missing or inadequate?
1. Commitment 2. Accountability 3. Involvement
4. Hazard Identification/Control 5. Accident Analysis 6. Training 7. Evaluation

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UNCOVERING SURFACE CAUSES

To begin this step, look at each event and underline the conditions and behaviors that may have directly
caused or contributed to an accident. Take a look at the sequence of events below. The conditions and
behaviors that may have contributed to the injury in events -11 and -9 are underlined. See if you can
find other surface causes that contributed to or directly caused the injury.

-11
Event ____ Feb 2 - 1330
Event -10
____ Feb 2 - 1335 Event -8
____ Feb 2 - 1337
Bob gets the six-foot -9
Event ____ Feb 2 - 1336 -7
Event ____ Feb 2 - 1337
step ladder from Bob carries ladder to the Ralph tells Bob to hurry up
overhead light in the Bob notices oil on his because the filter on the air Bob grabs the florescent
the storage room
warehouse that needs workshoes and wipes it off conditioning needs light with his left hand and
in the warehouse.
replacement. with a rag. replacement. climbs the step ladder.

-6
Event ____ Feb 2 - 1337 -5
Event ____ Feb 2 - 1337 -4
Event ____ Feb 2 - 1338
-3
Event ____ Feb 2 - 1338 -2
Event ____ Feb 2 - 1338
Bob lays the florescent Bob positions his feet on As Bob reaches to remove
light across the top the fourth rung of the the defective florescent Bob is startled and quickly The right side of the fourth
platform of the ladder. ladder (second from top). light, the replacement bulb reaches to catch the rung of the ladder
begins to roll off the ladder moving bulb before it falls separates from the leg of
platform. to the floor. the ladder.

-1
Event ____ Feb 2 - 1338
0
Event ____ Feb 2 - 1338 Event +1
____ Feb 2 - 1338 Event +2
____ Feb 2 - 1338
Bob's right foot slips
through the space between Bob's left leg buckles and Ralph and Betty see Bob
the fourth and fifth rung of Ralph tells Betty to hold the
he falls back striking his falling and rush to help him
ladder and carefully lifts
the ladder. back and head against the before the ladder falls.
Bob and helps him out of
ladder. the ladder.

After identifying all of the conditions and behaviors, list them in preparation for conducting root cause
analysis.

Event # Condition and/or Behavior

-11 Condition - inadequate equipment (six ft. ladder too short)

Behavior – selecting and using inadequate equipment

-9 Condition - inadequate equipment (oily safety shoes)

Behavior – cleaning oily shoes with a rag – no approved detergent used

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See if you can complete the list.

______ __________________________________________________________________

______ __________________________________________________________________

______ __________________________________________________________________

______ __________________________________________________________________

______ __________________________________________________________________

______ __________________________________________________________________

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UNCOVERING ROOT CAUSES

Now that you have developed a list of conditions and behaviors
that may have caused or contributed to the accident, you need to
find out why they exist or occurred. To do that, conduct a “5-Why”
Analysis to uncover the root causes. By asking why-questions,
you’ll eventually arrive at root causes.

There are a number of formats you can use to conduct 5-Why

Analysis. You can also write questions on sticky pads or index cards
as you see to the right, or you can use a more linear format like
that below.

Event -11. Bob used the six-foot ladder. Why?

It was the only ladder available. Why?

The other ten-foot ladder was disposed of six months ago
(October 6th). Why?
An employee told the safety committee (SC)
representative a rung on the ladder had been broken.
Why?
1. Employees are to report defective equipment to SC
reps. Why?
Hazard reporting procedures require
reporting safety concerns through SC reps.
2. Safety is “owned” by the SC. Why?
The SC rep told the supervisor the ladder
was defective and it should be thrown
away. Why?
SC reps are to report hazards to
supervisors. Why?
The procedure states SC reps, rather than
employees, are to report. Why?
Hazard Reporting Program attempts to maintain employee anonymity.

As you can see from the example above, a thorough root cause analysis will generate many questions.
More often than not, you’ll need to ask more than five “whys” for each condition or behavior under
question. To get the answers to your questions, you may need to conduct follow-up interviews over the
phone or via email.

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All of the answers to the questions in the previous example represent conditions and behaviors that also
may have contributed indirectly to the accident. I’m sure you can understand from this brief example
why our basic assumption when conducting an accident investigation should be that we need to
improve programs and procedures. Ultimately, in the example, our line of questioning would have led us
to the conclusion that we need to improve:

safety training of the supervisor, employees, and the safety committee

reporting and correction of hazardous conditions
the safety training plan
safety inspection plan, policies, and procedures
safety equipment purchasing policies and procedures

These questions cover four areas that should be reviewed in determining the root cause of hazards,
incidents, and accidents. It is not uncommon to find factors in each of the four areas: Management,
Employee, Equipment, and Environment.

Management Checklist
Did supervisor detect, anticipate, or report an unsafe or hazardous condition?
Did supervisor recognize deviations from the normal job procedure?
Did the supervisor and employees participate in job review sessions especially for those jobs
performed on an infrequent basis?
Were supervisors made aware of their responsibilities for the safety of their work areas and
employees?
Were supervisors properly trained in the principles of accident prevention?
Was there any history of personnel problems or any conflicts with or between supervisor and
employees or between employees themselves?
Did the supervisor conduct regular safety meetings with employees?
Were the topics discussed and actions taken during the safety meetings recorded in the
minutes?
Were the proper resources (e.g., equipment, tools, materials, etc.) required to perform the job
or task readily available and in proper condition?
Did the supervisors ensure employees were trained and proficient before assigning them to
their jobs?
Did management properly research the background and experience level of employees before
extending an offer of employment?

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Employee Checklist
Did a written or well-established procedure exist for employees to follow?
Did job procedures or standards properly identify the potential hazards of job performance?
Were employees familiar with job procedures?
Was there any deviation from the established job procedures?
Did any mental or physical conditions prevent the employee(s) from properly performing their
jobs?
Were there any tasks in the job considered more demanding or difficult than usual (e.g.,
strenuous activities, excessive concentration required, etc.)?
Was the proper personal protective equipment specified for the job or task?
Were employees trained in the proper use of any personal protective equipment?
Did the employees use the prescribed personal protective equipment?
Were employees trained and familiar with the proper emergency procedures, including the use
of any special emergency equipment?
Was there any indication of misuse or abuse of equipment and/or materials at the accident site?
Is there any history or record of misconduct or poor performance for any employee involved in
this accident?
If applicable, are all employee certification and training records current and up-to-date?
Was there any shortage of personnel on the day of the accident?

Equipment Checklist
Were there any defects in equipment (including materials and tools) that contributed to a
hazard or created an unsafe condition?
Were the hazardous or unsafe conditions recognized by management, employees, or both?
Were the recognized hazardous conditions properly reported?
Are existing equipment inspection procedures adequately detecting hazardous or unsafe
conditions?
Were the proper equipment and tools being used for the job?
Were the correct/prescribed tools and equipment readily available at the job site?
Did employees know how to obtain the proper equipment and tools?
Did equipment design contribute to operator error?
Was all necessary emergency equipment readily available?
Did emergency equipment function properly?
Is there any history of equipment failure for the same or similar reasons?
Has the manufacturer issued warnings, Safe-Alerts, or other such information pertaining to this
equipment?

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Were all equipment guards and warnings functioning properly at the time of the accident?

Environment Checklist
Did the location of the employees, equipment, and/or materials contribute to the accident?
Were there any hazardous environmental conditions that may have contributed to the
accident?
Were the hazardous environmental conditions in the work area recognized by employees or
supervision?
Were any actions taken by employees, supervisors, or both to eliminate or control
environmental hazards?
Were employees trained to deal with any hazardous environmental conditions that could arise?
Were employees not assigned to a work area present at the time of the accident?
Was sufficient space provided to accomplish the job?
Was there adequate lighting to properly perform all the assigned tasks associated with the job?
Did unacceptable noise levels exist at the time of the accident?
Was there any known leak of hazardous materials such as chemicals, solvents or air
contaminants?
Were there any physical environmental hazards, such as excessive vibration, temperature
extremes, inadequate air circulation, or ventilation problems?
If applicable, were there any hazardous environmental conditions, such as inclement weather,
that may have contributed to the accident?
Is the layout of the work area sufficient to preclude or minimize the possibility of distractions
from a passerby or from other workers in the area?
Is there a history of environmental problems in this area?

For a more complete list of surface and root causes, see Appendix 4 and 5.

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PHASE THREE: REPORT THE FACTS

The final two steps recommend and communicate corrective actions and management solutions to
make sure similar accident(s) does not recur.

Step 5. Recommend Corrective Actions and Program

Improvements
To correct hazards and effectively improve the safety and health management system, we need to
anticipate proactively potential hazards before they exist. Absent that, we need to control existing
hazards when they've been identified in the accident investigation. According to ANSI/AIHA Z10-2005
and best practices when taking corrective actions there are two primary control strategies
recommended:

1. Control the hazard.

2. Control exposure to the hazard.

CONTROLLING HAZARDS WITH ELIMINATION, SUBSTITUTION, AND ENGINEERING

CONTROLS
To "furnish a safe and healthful workplace," means to design the workplace so tools, equipment,
machinery, materials, and the work environment are free (if feasible) from hazards that could cause
injury or illness.

The most corrective action plan is to control the hazard because, after all, if you can get rid of the
hazard, you don't have to control employee exposure to the hazard. We do this through sound
engineering. There are three hazard control strategies:

1. Elimination
2. Substitution
3. Engineering

If hazard control strategies are not as effective as they need to be, you may need to also use exposure
control strategies.

If possible, your first priority should be to eliminate the hazard (no hazard = no accident). Why is this
control strategy our top priority? Employing an elimination control has the potential to completely
remove the hazard. We're somehow changing a thing/condition in the workplace.

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Substitute the hazard with a less hazardous condition, process or method. Some basic examples are
substituting a toxic chemical with a non-toxic chemical or replacing an old poorly-designed machine with
a new model.

Engineering controls typically use the following strategies to eliminate or reduce hazards:

Design: Design a tool so that it reduces the likelihood of strain or sprain.

Redesign: Change the design of a machine so that dangerous moving parts or electrical circuits
are out of reach.
Enclosure: Place a hood over a noisy printer. Place a machine guard around a dangerous moving
part.

It's important to note OSHA expects the employer to first try to eliminate, substitute or engineer the
hazard so it can no longer cause a serious injury. For instance, if a machine is producing unacceptable
noise, OSHA would expect the employer to first eliminate or reduce the noise level to acceptable levels
using one or more of these three strategies. In this instance, an engineering control such as enclosure
might work.

CONTROLLING EXPOSURES WITH ADMINISTRATIVE CONTROLS AND PERSONAL

PROTECTIVE EQUIPMENT
To "furnish work that is safe and healthful" means to design procedures and practices so employees are
free (if feasible) from exposure to hazards that could cause injury or illness. There are three exposure
control strategies:

1. Warnings
2. Administrative Controls
3. Personal Protective Equipment

Signs and labels that tell employees to "Keep Out" or to be cautious around a chemical that "May cause
eye irritation" are used to warn employees about hazards. Remember, employees do not necessarily
follow "posted" rules and warnings. They usually only follow "enforced" rules and warnings. Think about
that the next time you're driving down the highway. Do you drive at the posted speed limit, or the
enforced speed limit? Enough said.

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Administrative controls eliminate or reduce exposure to hazards through strategies such as changing
work habits, improving sanitation and hygiene practices, or making other changes in the way the
employee performs the job. The focus is on managing what employees do. There are three basic
management control strategies to eliminate or reduce exposure to hazards:

1. Practices
2. Procedures
3. Schedules

Practices
Some practices are very general in their applicability. They include housekeeping activities such as:

Removing tripping, blocking, and slipping hazards

Removing accumulated toxic dust on surfaces
Wetting down surfaces to keep toxic dust out of the air

Procedures
Procedures apply to specific jobs in the workplace. Use a job hazard analysis (JHA) to help develop
procedures. Here are some examples of procedures that may exist in a workplace:

Permit-required confined space entry procedures

Lockout/Tagout procedures
Forklift safety inspection procedures

Schedules
Measures aimed at reducing employee exposure to hazard by changing work schedules. Such measures
include:

Lengthened rest breaks

Additional relief workers
Exercise breaks to vary body motions
Rotation of workers through different jobs

Some jobs require PPE by law. PPE places a barrier between workers and the hazard. This control
strategy is used in conjunction with the other control strategies. It should not be used to replace them.
When other controls do not adequately eliminate or reduce hazards, PPE may be needed in addition to

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those strategies. Remember, PPE does not eliminate or reduce the hazard itself, it merely sets up a
barrier between you and the hazard. And, to be successful, it is highly dependent on the employee's
behavior.

The final three control strategies are less effective than elimination, substitution, and engineering
controls in the long term because they do not remove the hazard, itself. Rather, they merely attempt to
reduce exposure to hazards by controlling behavior, attempting to change the things we do or don't do.

As long as employees comply with the warning signs, administrative controls and wear PPE when
required, these control strategies will work. However, human beings are natural risk-takers, and it is
"normal" for us to want to work in the most efficient manner. Sometimes safe work procedures are not
perceived as efficient, so we may not want to use them.

Therefore, managers must regularly supervise employees to make sure they comply with warning signs,
procedures, and PPE requirements. Think about the "Murphy's Law" principle below. It certainly applies
to safety. Here's an important principle to remember:

“ANY SYSTEM THAT RELIES ON HUMAN BEHAVIOR IS

INHERENTLY UNRELIABLE.”

Step 6. Write the Report

The primary reason accident investigations fail to eliminate similar accidents is they address correcting
surface causes but fail to uncover root causes.

The report should not be completed until you have finished developing the sequence of events,
conducted surface and root cause analysis, and suggested corrective actions and program
improvements. Take a look at the basic sections of the accident investigation report below or see
Appendix 10.

SECTION I. BACKGROUND
Describe when and where the accident occurred, who was injured, eye/ear witnesses, and others who
were interviewed as part of the investigation.

SECTION II. DESCRIPTION OF THE ACCIDENT

Describe the sequence of relevant events prior to, during, and immediately after the accident. Attach
separate pages if necessary.

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SECTION III. FINDINGS AND JUSTIFICATION

Identify the surface causes and root causes of the accident. Be sure to explain why you believe they
caused or contributed to the accident. If the safety manager or staff conducts root cause analysis, they
will include their finding and justification related to the system weaknesses that contributed to the
accident.

SECTION IV. RECOMMENDATIONS AND RESULTS

Detail suggested immediate corrective actions that will reduce or eliminate the hazard and exposures
that caused the accident. Describe suggested changes in safety programs to improve the ability to
provide safety leadership, resources, enforcement, supervision, and training.

SECTION V. SUMMARY
Estimate costs of the accident, required investment, and future benefits of corrective actions.

SECTION VI. REVIEW AND FOLLOW-UP ACTIONS

Describe equipment/machinery repaired, training conducted, etc. Describe system components
developed/revised. Indicate persons responsible for monitoring the quality of the change. Indicate
review official.

SECTION VII. ATTACHMENTS

Photos, sketches, interview notes, etc. are often necessary and provide great supplements to the body
of the report.

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REFERENCES
Benner, Ludwig, and Kingsley Hendrick. Investigating Accidents With STEP, Marcel Dekker Inc., New York
and Basel, 1987.

Ferry, Ted S. Modern Accident Investigation and Analysis - Second Edition, John Wiley and Sons, Inc.,
New York, 1988.

Kuhlman, Raymond. Professional Accident Investigation, Institute Press, Loganville, 1977.

OSHA Safety and Health Topics: Accident Investigation -

http://www.osha.gov/SLTC/accidentinvestigation/index.html

The Investigation Process Research Library: http://www.iprr.org/

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APPENDICES
Appendix 1. Accident Types – Event or Exposure Leading to Injury
Struck-by - A person is forcefully struck by an object. The force of contact is provided by the
object. Example: a pedestrian is struck by a moving vehicle.
Struck-against - A person forcefully strikes an object. The person provides the force. Example: a
person strikes a leg on a protruding beam.
Contact-by - Contact by a substance or material that by its very nature is harmful and causes
injury. Example: a person is contacted by steam escaping from a pipe.
Contact-with - A person comes in contact with a harmful material. The person initiates the
contact. Example: a person touches the hot surface of a boiler.
Caught-on - A person or part of his/her clothing or equipment is caught on an object that is
either moving or stationary. This may cause the person to lose his/her balance and fall, be
pulled into a machine, or suffer some other harm. Example: a person snags a sleeve on the end
of a handrail.
Caught-in - A person or part of him/her is trapped, stuck, or otherwise caught in an opening or
enclosure. Example: a person’s foot is caught in a hole in the floor.
Caught-between - A person is crushed, pinched or otherwise caught between a moving object
and stationary object or between two moving objects. Example: a person’s finger is caught
between a door and its casing.
Fall-to-surface - A person slips or trips and falls to the surface he/she is standing or walking on.
Example: a person trips on debris in the walkway and falls.
Fall-to-below - A person slips or trips and falls to a surface level below the one he/she was
walking or standing on. Example: a person trips on a stairway and falls to the floor below.
Exertion - Someone over-exerts or strains him or herself while doing a job. Examples: a person
lifts a heavy object and repeatedly flexes the wrist to move materials; a person twists the torso
to place materials on a table. Interaction with objects, materials, etc., is involved.
Bodily reaction - Caused solely from stress imposed by the free movement of the body or
assumption of a strained or unnatural body position. A leading source of injury. Example: a
person bends or twists to reach a valve and strains back.
Exposure - Over a period of time, someone is exposed to harmful conditions. Example: a person
is exposed to levels of noise in excess of 90 dba for 8 hours.

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Appendix 2. Forms of Energy Causing Injury

The direct cause of injury is always the harmful transfer of some form of energy that results in tissue
damage. Below are some examples of various forms of energy transfer.

1. Mechanical Energy - components that cut, crush, bend, shear, pinch, wrap, pull, and puncture
as a result of rotating, transverse, or reciprocating motion.
2. Electrical Energy - low voltage electrical hazards (below 440 volts) and high voltage electrical
hazards (above 440 volts).
3. Chemical Energy - corrosive, toxic, flammable, or reactive (involving a release of energy ranging
from "not violent" to "explosive" and "capable of detonation"). Toxics include poisonous plants,
dangerous animals, biting insects and disease carrying bacteria, etc.
4. Kinetic (impact) Energy - the collision of objects in relative motion to each other including the
impact of a moving object against a stationary object, falling objects, flying objects, and flying
particles.
5. Potential (stored) Energy - sudden unexpected movement due to gravity, pressure, tension, or
compression.
6. Thermal Energy - extreme or excessive heat, extreme cold, sources of flame ignition, flame
propagation, and heat-related explosions.
7. Acoustic Energy - excessive noise and vibration.
8. Radiant Energy - relatively short wavelength energy forms within the electromagnetic spectrum,
including the potentially harmful characteristics of radar, infra-red, visible, microwave,
ultraviolet, x-ray, and ionizing radiation.
9. Atmospheric/Geologic/Oceanographic Energy - atmospheric weather circumstances such as
wind and storm conditions, geological structure characteristics such as underground pressure or
the instability of the earth's surface, oceanographic currents, wave action, etc.

Adapted with permission from:

Nelson & Associates

3131 E. 29th Street, Suite E
Bryan, Texas 77802
Tel 979-774-7755
Fax 979-774-0559
info@hazardcontrol.com
www.hazardcontrol.com

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Appendix 3. Types of Hazards

1. Falls - The most common types of accidents are falls to the same surface and falls to below. The
severity of injury from a fall depends on three factors:
Velocity of an initial impact
Magnitude of deceleration due to hardness of surface
Orientation of the body on impact
2. Impact - Impacts resulting in struck by and struck against may cause serious accidents. The
severity of injury from impacting objects depends on three factors:
Velocity of the impact
Characteristics of the object (size, hardness, shape, etc.)
Body part impacted
3. Mechanical - If it's mechanical, and it moves, it's a hazard. There are as many hazards created by
moving machine parts as there are types of machines. Mechanical hazards cause caught-in,
caught-on, and crush accidents that can cut, crush, amputate, break bones, strain muscles, and
even cause asphyxiation. Mechanical hazard motions include rotating, reciprocating, and
transverse. Mechanical hazard actions include cutting, shearing, bending, and punching.
4. Vibration and Noise - Tools, equipment, and machinery that vibrate at a low frequency can
injure a part of the body or the whole body. However, the most common sound-induced injury
is due to high-frequency vibration. Low-frequency vibration hazards exist in two primary
categories:
Segmental vibration - exposure to equipment that vibrates at various frequencies can
affect different parts of the body. For instance, the hands are most sensitive to
vibrations at 30-40 cycles per second. Internal organs can be affected by vibrations as
low as 4-10 cycles per second.
Whole-body vibration - very low frequencies can affect the entire body. For instance,
truck drivers experience continuous whole-body vibration as they travel. That's one
reason truck driving is considered one of the most hazardous tasks for lower back
injuries.
5. Toxics - Virtually all materials may be toxic to some extent. In the workplace, a material is toxic if
a small quantity can cause an injurious effect, such as tissue damage, cancer, mutations, etc. It's
important to consider the routes of entry of toxic materials into the human body. There are four
possible routes of entry:
Inhalation - breathing in toxics is the most common and dangerous route.
Ingestion - toxics enter through the gastrointestinal tract.
Absorption - toxics pass through the skin into the bloodstream.

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Injection - toxics may be injected into the body (e.g., a needle). This is the least
common, yet most direct, route of entry.
6. Heat and Temperature - Overexposure to heat and temperature extremes may result in a range
of injuries from burns to frostbite. Temperature indicates the level of heat present. The second
law of thermodynamics states that heat will flow from an area of higher temperature to one of
lower temperature. Heat is produced as a result of the following: chemical reaction,
combustion, electrical current, mechanical motion and metabolism. Heat is transferred by:
Convection - heat is transferred by molecules moving through a fluid, gas or liquid.
Radiation - occurs when a body's temperature is above absolute zero.
Conduction - heat is transferred through a substance or between substances without
physical movement of the substances itself.
7. Flammability/Fire - Fire may cause burn injuries. In order for combustion to take place, the fuel
and oxidizer (oxygen) must be present in gaseous form. Flammable materials include:
Fuel
Chemicals
Vegetation
Solvents
Refrigerants
Wood/paper
Cleaning agents
Insecticides
Fabrics
Lubricants
Plastics
Metals
Coatings
Hydraulic fluid
Rubber products
8. Explosives - The results of an explosion may range from minor injury to major catastrophe (e.g.,
Space Shuttle Challenger). Instantaneous release of gas, heat, noise, light and over-pressure
creates a wavefront that damages anything in its path. About 2 billion pounds of explosives are
used by industry annually in construction, mining, quarrying, and seismographic work. Many
types of explosions may occur:
Chemicals
Dusts
Solids

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Vapors
Gases
Equipment
9. Pressure Hazards - High- and low-pressure conditions in the workplace can result in injury.
Standard atmospheric pressure is 14.7 pounds per square inch (psi). High-pressure gas
distribution lines are considered high-pressure when operating at 2 psi or higher. The American
Society of Mechanical Engineers (ASME) rate boilers, which operate at more than 15 psi, as high-
pressure. The pressure in full cylinders of compressed air, oxygen, or carbon dioxide is more
than 2,000 psi. Examples of pressure hazards include:
Ruptured cylinders - the thrust generated by gas flowing through a puncture or rupture
of a cylinder can be 20 times greater than the weight of the cylinder and reach a velocity
of 50 feet per second in 1/10th of a second. The result: a missile.
Whipping hoses and lines - compressed air and water hoses can kill when end fittings
become loose. Such hoses and lines should be restrained by weighting with bags at
short intervals, chained, clamped, etc. Never try to grab a whipping hose or line: turn off
the controlling valve.
Water hammer - the effect caused by a sudden stop of liquid flow causing a shock wave
(water hammer) that can cause a line rupture.
10. Electrical Contact - Exposure to electrical current may cause injury or death. The voltage is not
so important as the amount of current. It doesn't take much current to kill. There are five
principle categories of electrical hazards:
Shock - Electrical shock is a sudden and accidental stimulation of the body's nervous
system by an electrical current. Look for bare conductors, insulation failures, the buildup
of static electricity, and faulty electrical equipment.
Ignition of combustible (or explosive) material - Ignition is usually caused by a spark,
arc, or corona effect (ionized gas allows a current between conductors).
Overheating - High current creates high heat that can result in fires, equipment
burnout, and burns to employees.
Electrical explosions - Rapid overheating of circuit breakers, transformers, and other
equipment may result in an explosion.
Inadvertent activation of equipment - Unexpected startup of equipment and machinery
can injure and kill. That's why we have lockout/tagout procedures.
11. Ergonomics - Improper lifting, lowering, pushing, pulling, and twisting can cause strains and
sprains. Ergonomic-related hazards are the most common source of injury in the workplace.
About 45% of all claims are related to ergonomics! Ergonomics hazards exist in:
The worker - physical/mental capability, preexisting conditions, etc.

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The task - work that includes high force, repetition, frequency and duration, and
inappropriate posture; the point of operation.
The environment - noise, temperature, humidity, color, etc.
12. Biohazards - Exposure to plants, animals or their products that may be infectious, toxic or
allergenic may cause illness and disease. People who work with animals, animal products or
animal wasted have a greater risk of infection. Biohazard agents include:
Bacteria - simple, one-celled organisms that may or may not be harmful.
Viruses - organisms that depend on a host cell for development and reproduction.
Fungi - may be small or large (mushroom) parasitic organisms growing in a living or dead
plant or animal matter.
Rickettsia - rod-shaped microorganisms that are smaller than bacteria and depend on a
host for development and reproduction. Microorganisms transmitted by fleas, ticks and
lice.
13. Workplace Violence - Workplace violence is any violent act that occurs in the workplace and
creates a hostile work environment that affects employees’ physical or psychological well-being.
A risk factor is a condition or circumstance that may increase the likelihood of violence occurring
in a particular setting. Risk factors include:
Employee contact with the public
Exchanging money
Selling/dispensing alcohol or drugs
Delivering passengers, goods or services
Mobile workplace (such as a taxicab or police cruiser)
Exposure to unstable or volatile persons (such as in health care, social services)
Employees working alone, late at night/early morning, or in small numbers
Employees working in high-crime areas
Employees guarding valuable property or possessions
Employees working in community settings
Employees deciding on benefits, or in some other way controlling a person's future,
well-being, or freedom (such as a government agency)

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Appendix 4. Surface Causes

Sensory and Perceptual Factors

Misjudgment of distance, clearance, speed, and so forth.

False perception caused by visual illusion. Conditions that impair visual performance:
o Featureless terrain (such as a desert, dry lake, water, snow)
o Darkness and poor visibility
o Smoke and changing smoke patterns
o Mountainous terrain or sloping runway
o Anomalous light effects that cause flicker vertigo
o Low contrast of objects to background or poor illumination
o View into bright sunlight or moonlight
o Shadows
o Whiteout snow conditions
Spatial disorientation and vertigo. Conditions that affect sense of body position:
o Loss of visual cues
o Adverse medical condition or physiological condition (alcohol and drug effects,
hangover, dehydration, fatigue, and so forth)
o Moving head up and down, looking in and out, and answering or using cell phones
Loss of situational awareness. Types:
o Geographic disorientation (such as deviation from route, loss of position awareness)
o General loss of situational awareness (such as failure to perceive hazardous condition)
o Erroneous situational assessment (misinterpretation of situation or condition)
o Failure to predict or anticipate changing conditions
o False hypothesis confirmation bias (persistent false perception or misconception of
situation)
Attention failure (such as failure to monitor or respond when correct information is available).
Types:
o Failure to visually scan outside the vehicle or equipment for hazards
o Omission of checklist items
o Failure to respond to communication or warning
o Control-action error:
Failure to set, move, or reset control switch (lapse)
Unintentional activation of control switch (slip)
Control-substitution error (slip)
Control-reversal error (slip)

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OSHAcademy The Ultimate Accident Investigator’s Guide

Control-adjustment or precision error (slip)

Conditions that affect attention and situational awareness:
o Inattention (focus on information unrelated to tasks)
o Channelization, fixation (psychological narrowing of perception)
o Distraction (preoccupation with internal [mental] event or with external event)
o Task overload due to systems (such as communications)
o Task overload due to equipment systems assignment factors
o Cognitive workload (problem-solving concentration or information overload)
o Habit influence or interference
o Excessive crew stress or fatigue
o Excessive workload or tasking
o Inadequate briefing or preparation
o Inadequate training or experience for assignment
o Negative learning transfer (such as during transition to new assignment)
o Adverse meteorological conditions
o Tactical-situation overload or display-information overload
o Inadequate crew motivation or inadequate vigilance
o Inadequate equipment design

Medical and Physiological Factors

Carbon monoxide poisoning

Self-medication (without medical advice or against medical advice)
Motion sickness
Incompatible physical capabilities
Overexertion while off duty
Influence of drugs or alcohol
Cold or flu (or other known illness)
Excessive personal stress or fatigue
Inadequate nutrition (such as omitted meals)
Hypoxia
Heat
Cold
Stress induced by heightened state of alertness
Effects of smoke
Dehydration
Other medical or physiological condition:

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OSHAcademy The Ultimate Accident Investigator’s Guide

o Assignment tasking or job fatigue (such as being on duty more than 14 hours, late-night
or early morning operations)
o Cumulative fatigue (such as excessive physical or mental workload, circadian disruption,
or sleep loss)
o Cumulative effects of personal or occupational stress (beyond stress-coping limit)
o Emergency condition or workload transition (from normal operation to emergency
operation)
o Medical or physiological preconditions (health and fitness, hangover, dehydration, etc.)

Knowledge and Skill Factors

Inadequate knowledge of systems, procedures, and so forth (knowledge-based errors). Types:

o Knowledge-based
o Inadequate knowledge of systems, procedures, etc.
o Used improper procedure
o Ill-structured decisions
o Failure to problem solve
Inadequate equipment control, or inadequate accuracy and precision of equipment
maneuvering (skill-based error). Types:
o Breakdown in visual scan
o Failure to see and avoid
o Over or under reacting
o Over or under controlling
o Inadequate experience for complexity of assignment
Misuse of procedures or incorrect performance tasks (rule-based error), such as:
o Failure to perform required procedure
o Use of wrong procedure or rule(s)
o Failure to conduct step(s) in prescribed sequence
Conditions that lead to inadequate operational performance:
o Lack or variation of standards
o Loss of situational awareness in varying environment
o Demonstration of performance below required proficiency standards or current
standards
o Demonstration of inadequate performance or documented deficiencies
o Inadequate essential training for specific task(s)
o Inadequate recent experience or inadequate experience
o Lack of sensory input
o Limited reaction time

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Assignment Factors

Failure of dispatch to provide correct critical information (such as frequencies, location, other
equipment, or resources)
Poor communication with other assets (such as ground or aircraft)
Inadequate or faulty supervision from ground or tactical aircraft
Lack or variation of standards
Non-participant or non-communicative equipment or resources at the scene
Loss of situational awareness in varying environment
Changing plans or tactics (change of teams on accidents)
Unanticipated change of radio frequencies
Intentional deviation from procedures
Unintentional deviation from procedures
Demonstration of performance below required proficiency standards or current standards
Demonstration of inadequate performance or documented deficiencies
Inadequate essential training for specific task(s)
Inadequate recent experience or inadequate experience for assignment
Transition (learning new equipment or operational systems)
Inadequate knowledge of tactical situation
Lack of sensory input
Limited reaction time
Conditions that lead to inadequate assignment performance:
o Smoke
o Wind shifts
o Changes in fire behavior
o Low visibility
o Unexpected equipment, resources, or aircraft
o Assignment intensity
o Assignment creep
o Assignment urgency
o Failure to recognize deteriorating conditions
o Time compression
o Diverts to new accidents
o Excessive communication demands
o Past assignment success based on high-risk behavior

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Personality and Safety Attitude

Overconfidence
Excessive motivation to achieve assignment
Reckless operation
Anger or frustration on the job
Stress-coping failure (such as anger)
Overly assertive or non-assertive
Inadequate confidence to perform tasks or activities
Acquiescence to social pressure (from organization or peers) to operate in hazardous situation
or condition
Failure to report or act upon incidents of misconduct
Toleration of unsafe acts and behaviors
Poor equipment or assignment preparation

Judgment and Risk Decision

Acceptance of a high-risk situation or assignment

Misjudgment of assignment risks (complacency)
Failure to monitor assignment progress or conditions (complacency)
Use of incorrect task priorities
Intentional deviation from safe procedure (imprudence)
Intentional violation of standard operating procedure or regulation. Types:
o Violation of orders, regulations, standard operating procedures (SOP)
o Crew rest requirements
o Inadequate training
o Violated agency policy or contract
o Failed to comply with agency manuals
o Supervisor knowingly accepted unqualified crew
o Failed to obtain valid weather brief
o Accepted unnecessary hazard
o Lacks adequate up-to-date qualifications for assignment
Intentional disregard of warnings
Non-compliance with personal limits
Non-compliance with published equipment limits
Non-compliance with prescribed assignment parameters
Acquiescence to social pressure (from organization or peers)
Conditions leading to poor safety attitude and risky judgment:

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o History of taking high risks (personality-driven)

o Pattern of overconfidence
o Personal denial of wrongdoing
o Documented history of marginal performance or failure
o Excessive motivation (did not know limits)
o Reputation as a reckless individual
o Failure to cope with life stress (anger or frustration)
o Overly assertive or non-assertive (interpersonal style)
o Influenced by inadequate organizational climate or safety culture (such as lack of
adequate supervision)

Communication and Crew Coordination

Inadequate assignment plan or brief

Inadequate or wrong assignment information conveyed to crew (dispatch or supervisor errors)
Failure to communicate plan or intentions
Failure to use standard or accepted terminology
Failure to work as a team
Inability or failure to contact and coordinate with ground or aviation personnel
Inadequate understanding of communication or failure to acknowledge communication
Interpersonal conflict or crew argument during assignment
Conditions leading to inadequate communication or coordination:
o Inadequate training in communication or crew coordination
o Inadequate standard operating procedures for use of crew resources
o Inadequate support from organization for crew coordination doctrine
o Failure of organizational safety culture to support crew resource management

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Appendix 5. Root Causes

System Design and Operation Factors

Use of wrong switch, lever, or control

Misinterpretation of instrument indication
Inability to reach or see control
Inability to see or interpret instrument or indicator
Failure to respond to warning
Selection or use of incorrect system-operating mode (mode confusion)
Overreliance on automated system (automation complacency)
Conditions that contribute to design-induced crew errors:
o Inadequate primary equipment control or display arrangement
o Inadequate primary display data or data format
o Inadequate hazard advisory or warning display
o Inadequate system instructions or documentation
o Inadequate system support or facilities
o Inappropriate type or level of automation or excessive mode complexity

Supervisory and Organizational Factors

Not adhering to rules and regulations

Inappropriate scheduling or crew assignment
Failure to monitor crew rest or duty requirements
Failure to establish adequate standards
Failure to provide adequate briefing for assignment
Failure to provide proper training
Lack of professional guidance
Undermining or failure to support crews
Failure to monitor compliance with standards
Failure to monitor crew training or qualifications
Failure to identify or remove a known high-risk employee
Failure to correct inappropriate behavior
Failure to correct a safety hazard
Failure to establish or monitor quality standards
Failure of standards, either poorly written, highly interpretable, or conflicting
Risk outweighs benefit
Poor crew pairing

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Excessive assignment tasking or workload

Inadequate assignment briefing or supervision
Intentional violation of a standard or regulation
Failure to perceive or to assess (correctly) assignment risks, with respect to:
o Unseen or unrecognized hazards
o Environmental hazards or operating conditions
o Assignment tasking and crew skill level
o Equipment limitations
Conditions leading to supervisory failures:
o Excessive operations or organizational workload (imposed by the organization or
imposed by organizational chain)
o Inadequate organizational safety culture
o Supervisor is over-tasked
o Supervisor is untrained
o Inattention to safety management (inadequate safety supervision)
o Inadequate work standards or low performance expectations
o Inadequate or poor example set by supervisors
o Inadequate safety commitment or emphasis by supervisors
o Organization lacks an adequate system for monitoring and correcting hazardous
conditions
o Supervisors fail to promote and reward safe behavior or quickly correct unsafe behavior
o Organization lacks adequate policies and procedures to ensure high quality work
performance
o Organization lacks adequate job qualification standards or training program
o Organization lacks adequate internal communication
o Organization had no system or an inadequate system for management of high-risk
employees
o Organization lacks adequate process or procedures for operational risk management
o Organization fails to provide adequate human factors training
o Organization fails to ensure sufficient involvement of medical and occupational health
specialists
o Organization fails to establish or enforce acceptable medical or health standards

Maintenance

Procedures
o Unwritten
o Unclear, undefined, or vague

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OSHAcademy The Ultimate Accident Investigator’s Guide

o Not followed
Records
o Discrepancies entered but not deferred or cleared
o Entries not recorded or not recorded in correct book(s)
o Improper entries or unauthorized signature or number
o Falsification of entries
Publications, manuals, guides
o Not current
o Were unused for the procedure
o Incorrect manual or guide used for procedure
o Not available
Training
o Not trained on procedure
o Training not documented
o Falsified
o Not current
Personnel
o Not properly licensed
o Insufficient (staffing)
o Improper or insufficient oversight
o Not properly rested
Management
o Non-existent
o Ineffective
o Understaffed
o Ineffective organization of assigned personnel
o Insufficiently trained
Quality assurance
o Non-existent
o Insufficiently trained
o Ineffective
o Not used when available
Inspection guides
o Unavailable
o Procedures not followed
o Insufficient
o Not current

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OSHAcademy The Ultimate Accident Investigator’s Guide

o Not approved
o Not signed off
o Falsified
o Unapproved signature or number
Tools or equipment
o Improper use or procedure
o Not calibrated
o Used improperly
o Not trained for the special equipment or tool
o Not used
o No tool control program

Source: USDA Accident Investigation Guide

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Appendix 6. Sketching Techniques

1. Make sketches large, preferably 8" x 10".
2. Makes sketches clear. Include information pertinent to the investigation.
3. Include measurements.
4. Print legibly. All printing should be on the same plane.
5. Indicate directions (i.e., north, south, east, or west).
6. Always tie measurements to a permanent point, such as a telephone pole or building.
7. Use sketches when interviewing people. You can mark where they were standing. Also, it can be
used to pinpoint where photos were taken.

LUMBER STORAGE AREA XYZ SAWMILL

N Lumber Piles

Intended direction
of travel Height Height Height
8 ft 8 ft 8 ft
ACCIDENT DETAILS
Time: 6:45 p.m.
Lighting: dusk
Deceased: 6’1” tall
Eye level of operator: 7’
Top of load: 9’4”
Bottom of load: 1’4”
Travel speed of load: 5 mph Location of deceased (face down) Photo
Operator visibility: very poor point
Direction of motion
of deceased

Operator

Height Height Height Height Height

8 ft 8 ft 8 ft 8 ft 8 ft

22” space

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Appendix 7. Sample Accident Investigation Witness Statement

Accident Investigation Witness Statement
Thank you for helping us analyze this incident, so we can prevent someone from getting hurt or sick in
the future. Accuracy is very important in helping us get to the root cause of this incident.

Worksite Information
Company Name ______________________________________________________________

Worksite Address ______________________________________________________________

Phone Number ______________________________________________________________

Employee Information
Employee Name ______________________________________________________________

Phone Number ______________________________________________________________

Job Title ______________________________________________________________

Work Station ______________________________________________________________

Accident Information
Accident Date ______________________________________________________________

Worksite ______________________________________________________________

Work Station ______________________________________________________________

Time ______________________________________________________________

Please describe what you saw and heard in chronological order.

What were you doing just before the incident?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

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What were you doing when the incident occurred?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

What did you do after the incident occurred?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

Please answer the questions below.

What was the condition of the tools, equipment, machinery, and materials involved in the incident?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

What was the work environment like? Was it very hot, cold, wet, slippery, windy, etc.?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

What was the type and condition of the Personal Protective Equipment (PPE) being used by the
injured person when the incident occurred?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

What was the instruction or training you and others received on the task being performed when the
incident occurred? Please describe the training you received.

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

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What was the direction of travel, fall, or final resting place of the vehicle or equipment and individual
involved in the accident? Draw a diagram, if appropriate.

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

Who else witnessed or heard the incident?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

How do you think we can prevent this type of incident in the future?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

Is there anything else you would like to add?

___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________
___________________________________________________________________________________

I certify the information above is true and accurate to the best of my

recollection.

Signature __________________________________________________ Date __________________

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Appendix 8. Sample Interview Questions

Who Questions

Who was injured?

Who saw the mishap?
Who first responded?
Who talked with the victim?
Who has done the same job before?
Who has trained the victim?
Who supervised the victim?
Who told the victim to do this work?
Who maintained this equipment?
Who inspected this equipment?
Who modified this equipment?
Who installed this equipment?

What Questions

What did the victim do prior to the accident?

What was the victim doing at the time of the accident?
What equipment was involved (serial number, model number, company number,
manufacturer's name)?
What is the normal process?
What was different this time?
What were the instructions?
What was the training?

Where Questions

Where was the victim at the time of the accident?

Where was the equipment?
Where was the witness?
Where was the first aid/emergency equipment?
Where was the supervisor?

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When Questions

What time did the accident take place?

Was it at the end of the shift?
Was it at the end of the week?
How long had the victim been working that day? That week?

How Questions

How does the equipment normally operate?

How did the equipment operate on this day?
How does the victim normally perform this job?
How did the victim perform this job this day?
How did the mishap occur?

General Questions to Keep in Mind during an Incident Investigation Interview

What was the injured person doing at the time of the accident? Performing an assigned task?
Maintenance? Assisting another worker?
Was the injured employee working on an unauthorized task? Was the employee qualified to
perform the task and familiar with the process, equipment, and/or machinery?
What were other workers doing at the time of the accident?
Was the proper equipment being used for the task at hand (e.g., screwdriver instead of can
opener to open a paint can, file instead of the grinder to remove the burr on a bolt after it was
cut)?
Was the injured person following approved procedures?
Is the process, operation, or task new to the area?
Was the injured person adequately supervised? What was the proximity and competency of the
supervision?
What was the location of the accident?
What were the physical and environmental conditions of the area when the accident occurred?
What immediate or temporary actions could have prevented the accident or minimized its
effect?
What long-term or permanent action could have prevented the accident or minimized its effect?
Had corrective action been recommended in the past but not adopted?

Other General Questions for the Injured and/or Other Affected Employees

Who trained you? How long ago? How often? When did you last receive training on this task?

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Have you received hazard recognition training prior to the accident? Other training?
How did the trainer determine you were trained? Did the trainer evaluate/test you? How did
you demonstrate this training?
Did you completely understand the training? Did the trainer ask if you understood?
Did management accept your years of experience as suitable training? Did they assume your
safety knowledge was already there?
Are you aware of the hazards of this task? Aware of the safety procedures? Aware of inspection
requirements?
Explain the process? Explain the hazards? Explain the safety procedures?
How often do you perform this process? Did you do anything different this time? Have you done
it that way before?
How often does the supervisor meet with you to discuss safety? Does the supervisor check on
your work? Spend time with you?
How often is the supervisor around? Does the supervisor know about this process?
Who do you take safety concerns to? Have the responses been sufficient?
Have there been any close calls before in this process? Was it reported? Was there an
investigation?
Are there inspections conducted? By who? Safety committee?
Have you observed anyone being disciplined for safety before?
What would you change about this task/process? What is the most dangerous part of your job?
Are you responsible for training others?
Was this process ever safeguarded?

Management-related Questions during an Incident Investigation

What has upper management done to educate and prepare supervisors on safety related
matters, i.e. training, accountability, etc.?
What has upper management done to educate and prepare workers on safety related matters,
i.e. training, policies, and procedures?
What direct knowledge does the supervisor have of the safety hazards of the job/process under
his/her control?
What training on safety has the supervisor received and is it documented?
How is the supervisor competent for observing and monitoring the employees’ task(s)? How
was competency determined?
Is the supervisor’s safety knowledge solely based on years of experience? Has it simply been
assumed the safety knowledge was there?
What is the supervisor’s knowledge of safety policies and procedures?

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Is there a disciplinary program in place and does it address safety?

Have you ever disciplined anyone for violating a safety rule?
Describe the safety instructions given to subordinates? Did you describe the safety hazards for
that particular task to the employee?
Are supervisors/management aware and familiar with OR-OSHA rules applicable to the
processes/tasks they oversee?
Do managers/supervisors have knowledge of the injuries/illnesses occurring in their area? If so,
what steps have been taken to prevent reoccurrence?
What knowledge of personal protective equipment requirements does the supervisor have and
does he/she enforce these requirements?
Describe/explain the applicable safety and/or health programs which relate to the accident?
(e.g., hazard communication, lockout/tagout, permit-required confined space, emergency
evacuation, exposure control, bloodborne, forklifts/crane safety, respirator).
How do you determine an employee is adequately trained? Who trains the trainer? Is, or how
often is follow up training conducted?
Do the supervisors sit in on the safety training? Has remedial training been
conducted/considered for some employees, if applicable?
How often do you monitor your subordinates work practices? Documented? Corrections or
commendations?
What direct involvement do supervisors have in the company safety and health programs?
Describe your understanding of the proper safe work procedures for the particular task the
injured employee was involved in?
Have you conducted a job hazard analysis on this particular task? If so, describe.
Was there a hazard report on this particular task/equipment before the accident? Describe the
hazard reporting system?
Do you conduct employee safety orientations? Did you conduct the safety orientation for the
worker involved in the accident?
Who decides what type of training should (or is) conducted?
Do you conduct safety inspections in your area?
Were you aware of any defects, deficiencies, or damage to the equipment involved in the
accident?
Were you aware of any work practice deficiencies in the person involved in the accident? Any
safety deficiencies in this person?
Had you observed this person working this task before? Observed working unsafely or
incorrectly?
Describe the maintenance program here? Preventative and continual?

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What do you think could have prevented this accident?

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Appendix 9. Sample Sequence of Events

Event -12 Gloria tells Steve to take over for Ralph, who is sick, and cut frame stock pieces for the
rest of the swing shift.

Event -11 Gloria shows Steve how to cut the frame stock using the table saw.

Event -10 Steve notices the table saw does not have a proper guard.

Event -9 Steve tells Gloria the saw guard is missing.

Event -8 Gloria tells Steve to, "be careful, I'll check with maintenance about the guard. We can't
stop work, or we won't make our numbers."

Event -7 Gloria leaves to do some paperwork in the office, and Steve begins to cut the frame
stock as directed.

Event -6 Steve uses a piece of stock as a push stick but it doesn't work, so he decides not to use
it.

Event -5 At 5:32 PM, Steve pushes a piece of frame stock toward an unguarded saw blade.

Event -4 At that same instant, Bob yells out, "Hey, Steve, get over here right now!"

Event -3 Steve yells back, "WHAT?" as he quickly turns his head to the left to respond to Bob.

Event -2 Steve turns his head and, as he does, his body twists to left.

Event -1 Steve's hand contacts the unguarded rotating table saw blade.

Event 0 The saw blade strikes and cuts (gashes) into Steve's hand between the thumb and
forefinger, almost amputating the thumb.

Event 1 Steve screams and falls to the floor unconscious.

Event 2 Hearing Steve yell, and seeing him fall to the floor, Bob immediately tells Gloria to call
911.

Event 3 Gloria calls 911 while Bob runs over to perform first aid on Steve's hand.

Event 4 Bob can't find the first aid kit, so he wraps Steve's hand with a rag.

Event 5 Gloria runs over to help Bob perform first aid.

Event 6 Eight minutes later the EMT's arrive and transport Steve to the hospital.

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Appendix 10. Sample Accident Investigation Report Form

Number _________ Date of Report_________

Prepared by ________________________ ____________________________

SECTION I. BACKGROUND

WHO

Victim Name _________________________________________________________

Witness (1) Name _________________________________________________________

Job Title ________________________ Length of Service ______________

Address ________________________________________________________

Phone (H) _________________________ (W) _________________________

Witness (2) Name _________________________________________________________

Job Title ________________________ Length of Service ______________

Address ________________________________________________________

Phone (H) _________________________ (W) _________________________

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WHEN

Date __________________ Time __________________ Work shift __________________

WHERE

Department _______________ Location _______________ Equipment ______________

SECTION II. DESCRIPTION OF THE ACCIDENT. (Describe the sequence of relevant events prior to,
during, and immediately after the accident. Attach separate page if necessary)

Events prior to: ____________________________________________________________

Injury event: ______________________________________________________________

Events after: ______________________________________________________________

SECTION III. FINDINGS AND JUSTIFICATIONS. (Attach separate page if necessary)

Surface Cause(s) (Unsafe conditions and/or behaviors at any level of the organization)

_________________________________________________________________________

Justification (Describe evidence or proof that substantiates your finding)

_________________________________________________________________________

_________________________________________________________________________

Root Cause(s) (Missing/inadequate Programs, Plans, Policies, Processes, Procedures)

_________________________________________________________________________

Justification (Describe evidence or proof that substantiates your finding)

_________________________________________________________________________

_________________________________________________________________________

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SECTION IV. RECOMMENDATIONS AND RESULTS (Attach separate page if necessary)

Corrective actions. (To eliminate or reduce the hazardous conditions/unsafe behaviors that directly
caused the accident)

______________________________________________________________________

Results. (Describe the intended results and positive impact of the change.)

______________________________________________________________________

System improvements. (To revise and improve the programs, plans, policies, processes, and procedures
that indirectly caused/allowed the hazardous conditions/unsafe behaviors.)

______________________________________________________________________

Results. (Describe the intended results and positive impact of the change.)

_______________________________________________________________________

SECTION V: SUMMARY (Estimate costs of accident. Required investment and future benefits of
corrective actions)

_______________________________________________________________________

SECTION VI: REVIEW AND FOLLOW-UP ACTIONS: (Describe equipment/machinery repaired, training
conducted, etc. Describe system components developed/revised. Indicate persons responsible for
monitoring quality of the change. Indicate review official.)

Corrective Actions Taken: Responsible Individual: Date Closed:

______________________________ ______________________ ____________

______________________________ ______________________ ____________

System improvements made: Responsible Individual: Date Closed:

______________________________ ______________________ ____________

______________________________ ______________________ ____________

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Person(s) monitoring status of follow-up actions: ________________________________

Reviewed by Title

________________________________________ ________________________________________

Date Department

________________________________________ ________________________________________

SECTION VII: ATTACHMENTS: (Photos, sketches, interview notes, etc.)

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SUPPLEMENTAL MATERIALS
Supplement 1. Safety Management Systems
It’s important for accident investigators to understand the cause-effect relationship as it relates to the
elements of a safety management system.

All systems have structure, inputs, processes, and outputs. A system may be thought of as an orderly
arrangement of interdependent activities and related procedures which implement and facilitate the
performance of a major activity within an organization (American Society of Safety Engineers, Dictionary
of Terms).

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Supplement 2. Sample Accident Analysis Team Kit

If you do not currently have an accident investigator’s kit, ask your Site Safety Representative or Joint
Health & Safety Committee to develop one and keep it on site. It’s important to have this equipment
ready to go so you can begin the investigation process in a timely manner.

ESSENTIAL
Camera, film, and flash Straight-edge ruler (can be used as a
Tape measure (preferably 100 foot) scale reference in photos)
Clipboard and writing pad Pens and/or pencils
Graph paper Accident investigation forms
Flashlight

HELPFUL
Accident investigator’s checklist Masking tape
Magnifying Glass Specimen containers
Sturdy gloves Compass
High visibility plastic tapes to mark off Ten 4-inch spikes
area Hammer
First aid kit Paint stick (yellow/black)
Cassette recorder and spare cassette Chalk (yellow/white)
tapes Protractor
Identification tags Video camera with tape
Scotch tape Investigator’s template

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Supplement 3. Photographic Evidence—General

One of the most useful tools the investigator can bring to the accident scene is a camera. The camera
shows the view seen by a witness and can record documents. Digital cameras and cameras that process
their own film are ideal for this application. Film from 35-millimeter cameras can be converted to digital
format if developed correctly.

While video cameras have their uses, photographs may be more useful because they can be enlarged,
printed in multiple copies, and placed in the factual section.

Depending on the accident’s complexity, a professional photographer may be needed.

PHOTOGRAPHIC DOCUMENTATION
Photographs do not have to be taken in the order the investigator intends to look at them. Shoot all the
distant and medium shots first. Those shots can be taken with a handheld camera without extra
equipment. Afterward, take close-up shots with a tripod, flash, or cable release. This method saves time
because you do not have to switch back and forth between the two types of photography.

The basic types of documentary photographs include:

1. Perishable Evidence - These photographs document things that are likely to change or disappear
if not photographed immediately. Such photographs may include shots of an accident’s
aftermath or a rescue in progress, gauge readings, ground scars, radio settings, fire damage, and
the positions of switches on equipment.
2. Aerial Views - When performing aerial photography, photographers need an aviation plan,
approved by the aviation unit officer. If possible, photograph aerial views early. The appearance
of the accident site from the air will change rapidly as investigators move through it. Important
locations on the ground can be marked with yellow flagging or other suitable material (for
example, a yellow fire shirt). Shoot from different angles and at different altitudes.
3. Overviews of the Scene - Photograph the equipment wreckage at the accident site from the
eight points of the compass (N, NE, E, SE, S, SW, W, and NW). If the accident scene is spread out,
try a series of overlapping pictures. The prints can be matched at their edges to create a
panoramic view.
4. Significant Scene Elements - Try to establish the terrain gradient through photographs.
Photograph ground scars to record information that will allow their size and depth to be
analyzed in the future.
5. Site Inventory - Photographs can help inventory the accident site and document personal
protective clothing equipment and other safety equipment, including the victim’s personal

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effects and clothing. The location of each item may be plotted on a scaled map using a fixed
point of reference.
6. Close-ups - Bracket exposures for close-ups by taking two photographs with slightly different
exposure adjustments. Use a tripod or monopod, as appropriate.
7. Documents - Photographs can be used to record documents that cannot be retained. Such
documents include licenses and logbooks, or maps and charts.
8. Witnesses’ Views - It may be important to document the witnesses’ views of the accident.
Because the witnesses may have had wide-angle views, use a tripod and the panoramic
technique to duplicate the views with photographs.
9. Exemplars - An exemplar is a model or a pattern for an actual object. Sometimes it is difficult to
tell from a wreckage photograph what the part or component is supposed to look like. In some
investigations, it is important to have pictures of an identical undamaged part or component for
comparison.
10. Presentation - Photographs used in the factual section should be mounted and have captions
attached. An example of a documentary caption would be: “View of damaged driver’s door
looking north.” Each photo should include the name of the photographer and the date the
photo was taken.

PHOTOGRAPHIC EVIDENCE

Accident Location

Name of photographer Date and time photograph was taken

Camera type Film ASA Photograph number

Description of photograph:

Source: USDA Accident Investigation Guide

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Supplement 4. “Fix the System” Incident/Accident Analysis Plan

A. GENERAL POLICY
____________________ considers employees to be our most valued asset and as such we will ensure
that all incident and accidents are analyzed to correct the hazardous conditions, unsafe practices, and
improve related system weaknesses that produced them. This incident/accident analysis plan has been
developed to ensure our policy is effectively implemented. ____________________ will ensure this plan
is communicated, maintained and updated as appropriate.

B. INCIDENT/ACCIDENT REPORTING

We can’t analyze incidents and accidents if they are not reported. A common reason they go unreported
is the incident/accident analysis process is perceived to be a search for the “guilty party” rather than a
search for the facts. We agree with current research indicating most accidents are ultimately caused by
missing or inadequate system weaknesses. Management will assume responsibility for improving these
system weaknesses. When we handle incident/accident analysis as a search for facts, employees are
more likely to work together to report incidents/accidents and to correct deficiencies, be they
procedural, training, human error, managerial, or other. Consequently, our policy is to analyze accidents
to primarily determine how we can fix the system. We will not investigate accidents to determine
liability. A “no-fault” incident/accident analysis policy will help ensure we improve all aspects of our
manufacturing process.

All employees will report immediately to their supervisor, any unusual or out of the ordinary condition
or behavior at any level of the organization that has or could cause an injury or illness of any kind.
Supervisors will recognize employees immediately when an employee reports an injury or a hazard that
could cause serious physical harm or fatality, or could result in production downtime.

_____________________ will ensure effective reporting procedures are developed so we can quickly
eliminate or reduce hazardous conditions, unsafe practices, and system weaknesses.

C. PRE-PLANNING
Effective incident/accident analysis starts before the event occurs by establishing a well thought-out
incident/accident analysis process. Preplanning is crucial to ensure accurate information is obtained

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before it is lost over time following the incident/accident as a result of cleanup efforts or possible
blurring of people’s recollections.

D. INCIDENT/ACCIDENT ANALYSIS
All supervisors are assigned the responsibility for analyzing incidents in their departments. All
supervisors will be familiar with this plan and properly trained in analysis procedures.

Each department supervisor will immediately analyze all incidents (near hits) that might have resulted in
serious injury or fatality. Supervisors will analyze incidents that might have resulted in minor injury or
property damage within 4 hours from notification.

The supervisor will complete and submit a written incident/minor injury report through management
levels to the plant superintendent. If within the capability/authority of the supervisor, corrective actions
will begin immediately to eliminate or reduce the hazardous condition or unsafe work practice that
might result in injury or illness.

E. MANAGEMENT RESPONSIBILITIES
When our company has an incident/accident such as a fire, release, or explosion emergency,
management will:

1. Provide medical and other safety/health help to personnel;

2. Bring the incident under control; and
3. Investigate the incident effectively to preserve information and evidence.

To preserve relevant information, the analyst will:

1. Secure or barricade the scene;

2. Immediately collect transient information;
3. Interview personnel.

F. INCIDENT/ACCIDENT ANALYSIS TEAM

Background
It is important to establish incident/accident analysis teams before an event occurs so the team can
quickly move into action if called on. The makeup of the team is another important factor affecting the
quality of the analysis. We will appoint competent employees who are trained and have the knowledge
and skills necessary to conduct an effective analysis. Doing so will show management’s commitment to
the process.

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Although team membership may vary according to the type of incident, a typical team analyzing an
incident/accident may include:

1. A third-line or higher supervisor from the section where the event occurred
2. Personnel from an area not involved in the incident
3. An engineering and/or maintenance supervisor
4. The safety supervisor
5. A first-line supervisor from the affected area
6. Occupational health/environmental personnel
7. Appropriate wage personnel (i.e., operators, mechanics, technicians)
8. Research and/or technical personnel

Team member Department

_____________________________ ___________________________

_____________________________ ___________________________

_____________________________ ___________________________

The incident/Accident Analysis team leader will:

1. Control the scope of team activities by identifying which lines of analysis should be pursued,
referred to another group for study, or deferred;
2. Call and preside over meetings;
3. Assign tasks and establish timetables;
4. Ensure no potentially useful data source is overlooked; and,
5. Keep site management advised of the progress of the analysis process.

G. DETERMINING THE FACTS

A thorough search for the facts is an important step in incident/accident analysis. During the fact-finding
phase of the process, team members will:

1. Visit the scene before the physical evidence is disturbed.

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2. Sample unknown spills, vapors, residues, etc., noting conditions which may have affected the
sample (Be sure you sample using proper safety and health procedures).
3. Prepare visual aids, such as photographs, field sketches, missile maps, and other graphical
representations with the objective of providing data for the analysis.
4. Obtain on-the-spot information from eyewitnesses, if possible. Interviews with those directly
involved and others whose input might be useful should be scheduled soon thereafter. The
interviews should be conducted privately and individually; so the comments of one witness will
not influence the responses of others.
5. Observe key mechanical equipment as it is disassembled. Include as-built drawings, operating
logs, recorder charts, previous reports, procedures, equipment manuals, oral instruction, change
of design records, design data, records indicating the previous training and performance of the
employees involved, computer simulations, laboratory tests, etc.
6. Determine which incident-related items should be preserved. When a preliminary analysis
reveals an item may have failed to operate correctly, was damaged, etc., arrangements should
be made to either preserve the item or carefully document any subsequent repairs or
modifications.
7. Carefully document the sources of information contained in the incident report. This will be
valuable should it subsequently be determined that further study of the incident or potential
incident is necessary.

H. DETERMINING THE CAUSE

It is critical to establish the root cause(s) of an incident/accident so that effective recommendations are
made to correct the hazardous conditions and unsafe work practices, and make system improvements
to prevent the incident from recurring. The incident/accident analysis team will use appropriate
methods to sort out the facts, inferences, and judgments they assemble. Even when the cause of an
incident appears obvious, the investigation team will conduct a formal analysis of the event to make
sure any oversight or a premature/erroneous judgment is not made. Below is one method to develop
cause and effect relationships.

1. Develop the chronology (sequence) of events which occurred before, during, and after the
incident. The focus of the chronology should be solely on what happened and what actions were
taken. List alternatives when the status cannot be definitely established because of missing or
contradictory information.
2. List conditions or circumstances which deviated from normal, no matter how insignificant they
may seem.
3. List all hypotheses of the causes of the incident based on these deviations.

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I. RECOMMENDING CORRECTIVE ACTIONS AND SYSTEM IMPROVEMENTS

Usually, making recommendations for corrective actions and system improvements follow in a rather
straightforward manner from the cause(s) that were determined. A recommendation for corrective
action and system improvement will contain three parts:

1. The recommendation itself, which describes the actions and improvements to be taken to
prevent a recurrence of the incident.
2. The name of the person(s) or position(s) responsible for accomplishing actions and
improvements.
3. The correction date(s).

J. FOLLOW-UP SYSTEM
To make sure follow-up and closure of open recommendations, ___________________ will develop and
implement a system to track open recommendations and document actions taken to close out those
recommendations. Such a system will include a periodic status report to site management.

K. COMMUNICATING RESULTS
To prevent recurring incidents we will take two additional steps:

1. Document findings; and

2. Review the results of the analysis with appropriate personnel.

Incident documentation will address the following topics:

1. Description of the incident (date, time, location, etc.)

2. Facts determined during the analysis (including chronology as appropriate)
3. Statement of causes
4. Recommendations for corrective and preventive action (including who is responsible and
correction date)

Note: The purpose of this process is to analyze the incident/accident event to evaluate the degree to
which the safety management system may have contributed to the accident. It is not the purpose of this
process to determine personal fault. Do not include accusatory statements that place blame.

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L. REVIEW AND APPROVAL

Appropriate operating, maintenance and other personnel will review all incident/accident analysis
reports. Personnel at other facilities will also review the report to avoid a similar occurrence of the
incident.

Plan prepared by _____________________________ Date _______________________

Plan reviewed by _____________________________ Date _______________________

Plan approved by _____________________________ Date _______________________

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