Course 700 - Introduction to Safety Management

Safety guides and audits to make your job as a safety professional easier

Element 6: Accident Investigation


Fix the system, not the blame.
Fix the system, not the blame.
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The process of analysis is extremely important in identifying and eliminating those conditions, behaviors and system weaknesses that result in workplace accidents. In this module, we'll be discussing the various concepts, principles and procedures related to the analysis process so that you can, hopefully, transform your workplace, as close as possible, into a "risk free" zone.

Fix the system not the blame!

If your safety program fails to eliminate workplace hazards, chances are very likely an accident will result. When it does, it's important to conduct an effective accident investigation. Wait a minute! Did I say "investigation"? You'll hear that term most of the time, but when you do, understand the process is actually not so much an investigation as it is an analysis with the ultimate goal of fixing the safety management system.

In some workplaces, the term "investigation" implies that the primary purpose of the activity is to establish blame. That may be why OSHA conducts their investigations, but to be most effective, you can't afford to get stuck in that rut. Accident investigations should be performed for the express purpose of improving your safety management system - not the blame. The only way to receive any long-term benefit from accident analysis is to make sure system weaknesses are uncovered and permanently corrected.

Although accident investigation is a valuable and necessary tool to help reduce accident losses, it is always considerably more expensive to rely on accident investigation than hazard analysis as a strategy to reduce losses and eliminate hazards in the workplace. In some cases it may cost hundreds of thousands of dollars more as a result of direct, indirect, and unknown accident costs.

But, when the accident happens - it happens. And it's important to minimize accident costs to the company. This can be done if effective accident investigation procedures are used. That's what we'll be discussing in this module.

1. The purpose of an accident investigation is to fix the _____, not the _____.

a. system, blame
b. behavior, employee
c. blame, system
d. condition, behavior

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Accidents Just Happen...Don't They?

Many near-miss incidents reveal there are still safety issues that need to be fixed.
Near-miss incidents indicate safety deficiencies may exist.
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Do they? Are they really unexpected or unplanned?

If a company has 20 disabling injuries one year, and sets an objective to reduce the accident rate by 50% by the end of the next year, aren't they planning 10 accidents for that year? If they reach that goal, won't they be happy and content? They might say, "Hey, let's kick our feet up, pat ourselves on the back, and relax!" Is that really acceptable? You can't ever afford to relax, or be content in your safety performance.

Severity - Just a Matter of Luck

Historically, safety professionals have assumed that for every fatality, there would be a greater number of serious injuries, an even higher number of minor injuries, and even more near misses. While these ratios might be true for large samples, we do not believe you can make this assumption for small samples experienced within one company. We should not assume that if we reduce the number of minor injuries, we will automatically reduce the number of serious injuries. It just doesn't work. After all, the severity of an injury is much more a function of plain luck than repetitions in exposure.

For instance, if five painters fall off the same ladder at different times throughout the year, the severity of the injury each painter suffers will depend on their orientation when they impact the surface: and that's the result of any number of variables. Every one of the five falls might result in a serious injury. On the other hand, they might all result in no injury. It's not the number of falls that determines the nature of the injuries: it's the unique variables inherent in each fall - and that depends on just plain luck - the roll of the dice.

2. More than anything else, what does the severity of an injury depend on?

a. The age of the worker being injured
b. Just plain luck
c. The type of accident that occurs
d. The number of times a given accident occurs

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Incident and Accident Defined

Incidents vs. Accidents
Incidents vs. Accidents
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What is the difference between an incident and an accident? We'll use the following definitions for these two terms in this module:

  • An incident is an unexpected event that may result in property damage, but does not result in an injury or illness . Incidents are also called, "near misses," or "near hits."
  • An accident is an unexpected event that may result in property damage, and does result in an injury or illness to an employee.

A typical accident is the result of many related and unrelated factors (conditions, behaviors) that occur sometime, somewhere that somehow all directly or indirectly contribute to the injury event or accident. It is estimated that there are usually more than ten factors that contribute to a serious accident. Other experts claim there are over 20 factors somehow contribute to most serious accidents. What's the point here? Explaining why an accident occurred may not be an easy task.

3. A(n) _____ is an event that results in an injury or illness.

a. incident
b. accident
c. near-miss
d. near-hit

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Plan The Work - Work The Plan!

Be ready to investigate.
Be ready to investigate.
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When a serious accident occurs in the workplace, everyone will be too busy dealing with the emergency at hand to worry about putting together an investigation plan, so the best time to develop effective accident investigation procedures is before the accident occurs. The plan should include as a minimum procedures that determine:

  • Who should be notified of accident.
  • Who is authorized to notify outside agencies. (fire, police, etc.)
  • Who is assigned to conduct investigations.
  • Training required for accident investigators:
  • Who receives and acts on investigation reports.
  • Timetables for conducting hazard correction.

4. Which of the following determinations should NOT be part of the Accident Investigation Plan?

a. Who is at fault and resulting discipline
b. Who is assigned to conduct the investigation
c. Who receives and acts on investigation results
d. Who should be notified of the accident

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Accident Scenario

First, you must secure the accident scene.
First, you must secure the accident scene.
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You've just been notified of an injury in the workplace and immediately swing into action. You grab your investigator's kit and hurry to the accident scene. By the time you get there, the Emergency Medical Team (EMT) is administering first aid. It's a serious accident so the victim is transported to the hospital. Now it's safe to investigate.

What's Next? Secure the scene.

The first task after you arrive is to secure the accident scene, but don't start until it's safe to do so. And, you don't want to get in the way of emergency responders. The easiest way to do this is to place yellow warning tape around the area. If tape is not available, warning signs or guards may be required. Make sure nothing is moved because you'll be taking photos and measurements later.

Remember, at the request of OSHA, the employer must mark for identification, materials, tools or equipment necessary to the proper investigation of an accident. It is important that material evidence does not somehow get lost or "walk off" the scene.

5. What is the first thing that needs to happen before investigating an accident at work?

a. Start writing an accident report
b. Send all workers home
c. Secure the scene
d. Nothing, leave the scene alone

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Gathering Facts

Accident Investigation Tools
Accident Investigation Tools
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The next step in the procedure is to gather useful information about what directly and indirectly contributed to the accident.

Interviewing eyewitnesses to the accident is probably one of the most important techniques in gathering information. Take initial statements from eyewitnesses and others. They can give you a lot of information about the circumstances surrounding the accident. You should tell those who you initially interview that you may conduct follow-up interviews if more questions surface. Interview other interested persons such as supervisors, co-workers, etc.

Primary Investigation tools include:

  • Taking photographs of the scene.
  • Videotaping the scene.
  • Making sketches of the scene.
  • Making observations about the scene.
  • Taking measurements.

You should also review any records associated with the accident, including:

Gathering the facts reviews root cause.
Gathering the facts reveals root cause.
  • Training records
  • Disciplinary records
  • Medical records (as allowed)
  • Maintenance records
  • EMT reports
  • Police reports (rare)
  • Coroner's report (fatalities)
  • OSHA 300 Log (past similar injuries)
  • Safety Committee records

Remember you are gathering information to use in developing a sequence of steps that led up to the accident. You are ultimately trying to determine surface and root causes for the accident. It is not your job, as an accident investigator, to place blame. Just gather the facts.

6. What is one of the most important techniques for gathering information during an accident investigation?

a. Taking photographs of the scene
b. Interviewing eyewitnesses
c. Including measurements
d. Observing the scene

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Determine the Sequence of Events

Like dominoes, an accident is the final event in a sequence of events.
Like dominoes, an accident is the final event in a sequence of events.
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Now you've gathered tons of information about the accident, and it's piled high on your desk. What do you do with it? It's important that you read through the information initially to develop an accurate sequence of events that led up to and included the actual injury event. See what an accident investigation sequence of events might look like. OSHAcademy Online Safety Training Course 702, Effective Incident/Accident Investigation, covers this topic in more detail.

It's important to understand that the attempt to determine fault is inappropriate at any time during the investigation. If the purpose of the investigation is to determine blame, the investigation stops once blame seems to be determined. When the investigation stops, root causes are not determined.

On the other hand, in a "fix-the-system" safety culture, analysis is more in-depth and focused on finding system weaknesses, not fault. The question of fault is not appropriate and does not occur until the degree to which system weaknesses contributed to the accident has been determined. If system weaknesses did not, in any way, contribute to the accident, the question of discipline be carefully addressed after the investigation report has been completed.

7. When is it appropriate to discuss the question of discipline during the investigation?

a. When OSHA tells you who is responsible for the accident
b. When the surface causes point to the person at fault
c. As soon as it becomes obvious who committed the safety violation
d. It is never appropriate during the investigation process

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Determine the Causes

After developing the sequences of events, the next step is to determine surface causes. This step may be difficult because you are first searching for the surface causes of the accident in each step. This can take some time. From the clues you uncovered during this phase of the analysis, you'll be able to determine the system weaknesses or root causes.

Surface Causes

Primary surface causes point to secondary surface causes.
Primary surface causes point to secondary surface causes.
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As we mentioned earlier, surface causes are the conditions and behaviors that directly or indirectly produce the accident. A readily apparent reason for an accident/incident usually appears early in an accident/incident investigation. A long-lasting corrective action does not come from a surface cause. A surface cause leads to a root cause.

  • Primary surface causes directly cause the accident and usually involve the victim and some object or behavior.
  • Secondary surface causes are unique conditions or behaviors that indirectly contribute to the accident. Secondary surface causes can occur anytime, by any person in the organization, and at any location.

Conditions are objects or "states of being." Behaviors describe some sort of action, activity. Here are some examples:


  • Unguarded saw (condition)
  • Horseplay (behavior)
  • Not using hearing protection when required (behavior)
  • Slippery floor (condition)
  • Inadequately trained employee (condition)

8. _____ can occur anytime, by any person in the organization, and at any location.

a. Primary surface causes
b. Secondary surface causes
c. Root causes
d. Actual causes

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Determine the Causes (Continued)

Root Causes

Performance root causes point to system design root causes.
Performance root causes point to system design root causes.
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Root causes are the underlying system weaknesses that indirectly produce the primary and secondary surface causes leading to the accident incident/accident. The system weaknesses always exist prior to the surface causes that produced the accident. They are the programs, policies, plans, processes, and procedures in any of the seven elements or activity areas in a safety management system. It takes more in-depth investigation and results in long-lasting corrective action that can prevent repetition of the accident. A root cause may be referred to as a "basic" cause in OSHA accident investigation reports.

  • Inadequate or missing safety training plan.
  • No clearly stated supervision.
  • No inspection procedures.
  • Inadequate hazard reporting process.
  • Inadequate purchasing policy.
  • No progressive discipline process.

Listen to a short clip by Steve Geigle on defining surface and root causes:

9. Which of the following is an example of a root cause system weakness?

a. A defective tool
b. Inadequate safety training plan
c. An employee with a poor attitude
d. A supervisor who ignores safety rules

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The Accident Report

Recommend corrective actions and system improvements.
Recommend corrective actions and system improvements.
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Now that you have developed the sequence of steps leading up to, and including the accident, and determined surface and root causes, it's time to report your findings. Some employers also ask accident investigators to make recommendations for corrective action, so be prepared for that.

Most companies purchase accident investigation forms. That's fine, but some forms leave little room to write the type of detailed report that is necessary for a serious accident. If you use such a form, make sure you attach important information like the sequence of events, and findings which include both surface and root causes.

A better idea is to develop your own report form that includes the following five sections:

Section One - Background Information: This is the who, what, where, when, why, etc. It merely tells who conducted the inspection, when it was done, who the victim was, etc: Just a fill-in-the-blank section.

Section Two - Description of the Accident: This section includes the sequence of events you developed to determine cause. Just take the numbers off, and make a nice concise paragraph that describes the events leading up to, and including the accident.

Section Three - Findings: This section includes a description of the surface and root causes associated with the accident. List the surface causes first, and then their associated root causes. Remember, your investigation is to determine cause, not blame. It's virtually impossible to blame any one individual for a workplace accident. Don't let anyone pressure you into placing blame.

Section Four - Recommendations: This section may be part of your report if requested by your employer. Recommendations should relate directly to the surface and root causes for the accident. For instance, if one of the surface causes for an accident was a slippery floor, the related recommendation should address eliminating or substituting the hazard, engineering controls, administrative controls, and personal protective equipment (PPE).

It's crucial that, after making recommendations to eliminate or reduce the surface causes, you use the same procedure to recommend actions to correct the root causes. If you fail to do this, it's a sure bet that similar accidents will continue to occur.

Section Five - Summary: In this final section, it's important to present a cost-benefit analysis. What are the estimated direct and indirect costs of the accident being investigated? These represent potential future costs if a similar accident were to occur. Compare this figure with the costs associated with taking corrective action? You may want to address return on investment also. Information on cost benefit analysis is presented in OSHAcademy Course 702.

Well, there it is. Remember, an effective accident investigation program will help to prevent similar accidents from happening and minimize accident costs. OK, ace detective, it's time to take the quiz.

10. What will happen if you fail to correct system weaknesses identified in an accident?

a. Similar accidents will occur
b. Employees will thank you for it
c. The company will save money
d. You won't discover who was at fault

Check your Work

Read the material in each section to find the correct answer to each quiz question. After answering all the questions, click on the "Check Quiz Answers" button to grade your quiz and see your score. You will receive a message if you forgot to answer one of the questions. After clicking the button, the questions you missed will be listed below. You can correct any missed questions and check your answers again.