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Course 702 - Effective Accident Investigation

The Basics

A maze where you must start from the finish and find your way to the start
Start the investigation at the finish and work backwards.

The best metaphor for how accidents are investigated is a simple maze. If a group of people are asked to solve the maze as quickly as possible and ask the "winners" how they did it, invariably the answer will be that they worked it from the Finish to the Start. Most mazes are designed to be difficult working from the Start to the Finish, but are simple working from the Finish to the Start. Like a maze, accident investigations look backwards. What was uncertain for the people working forward through the maze becomes clear for the investigator looking backwards. (Source: DOE)

What is an Accident?

An accident is the final event in an unplanned process that results in injury or illness to an employee and possibly property damage. It is the final result or effect of a number of surface and root causes.

  • An "event," occurs when one "actor" (one person/thing) performs an "action" (does something).
  • A person or thing (equipment, tools, materials, etc.) will do something that results in a change of state.
  • An accident may be the result of many factors (simultaneous, interconnected, cross-linked events) that have interacted in some dynamic way.

Accidents and Incidents

Workplace accidents are part of a broad group of events or occurrences leading to a physical or psychological injury. Workplace incidents adversely affect the completion of a task but do not result in an employee injury. For simplicity, the procedures discussed in this course apply most appropriately to accidents, but they are also applicable to all incidents in general. Think of it this way:

Accidents cause injuries: incidents do not.

Quiz Instructions

Each section in this course will include a quiz question at the bottom of the page. In the last section, you'll be able to check your score and retake the quiz if desired. Be sure to answer all questions or you won't see your score. To improve your score after you get results, just go back through the sections and change your answers. Do not refresh these pages or you'll have to answer all questions again.

1. An accident is the _____ in an _____ process.

a. end results, expected outcome
b. final event, unplanned
c. unexpected outcome, unexpected happening
d. a planned, expected happening

Accident Types

Safety Memo - The Accident Cascade.

An accident isn't just an event that you can lump into one big category. In reality, there are many different types of accidents. Let's take a look at a partial list.

  • Struck-by: A person is forcefully struck by an object. The force of contact is provided by the object.
  • Struck-against: A person forcefully strikes an object. The person provides the force or energy.
  • Contact-by: Contact by a substance or material that, by its very nature, is harmful and causes injury.
  • Contact-with: A person comes in contact with a harmful substance or material. The person initiates the contact.
  • 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.
  • Caught-in: A person or part of him/her is trapped, or otherwise caught in an opening or enclosure.
  • Caught-between: A person is crushed, pinched or otherwise caught between a moving and a stationary object, or between two moving objects.
  • Fall-to-surface: A person slips or trips and falls to the surface he/she is standing or walking on.
  • Fall-to-below: A person slips or trips and falls to a level below the one he/she was walking or standing on.
  • Overexertion: A person over-extends or strains himself/herself while performing work.
  • Bodily reaction: Caused solely from stress imposed by free movement of the body or assumption of a strained or unnatural body position. A leading source of injury:
  • Overexposure: Over a period of time, a person is exposed to harmful energy (noise, heat), lack of energy (cold), or substances (toxic chemicals/atmospheres).

2. This type of accident is likely to occur if a worker carries a box that is too heavy.

a. Overexertion
b. Bodily reaction
c. Fall-to-below
d. Fall-to-surface

Are Accidents Always Unplanned?

Employees cleaning windows using boatswain chairs and fall protection
Accidents are unplanned, or are they?

We like to think that accidents are unexpected or unplanned events, but sometimes, that's not necessarily so. Some accidents result from hazardous conditions and unsafe behaviors that have been ignored or tolerated for weeks, months, or even years. In such cases, it's not a question of "if" the accident is going to happen: It's only a matter of "when." But unfortunately, the decision is made to take the risk.

A competent person can examine workplace conditions, behaviors and underlying systems to predict closely what kind of accidents will occur in the workplace. Technically, we can't say an accident is always unplanned. Like any system, a safety management system is designed perfectly to produce what it produces. Consequently, written safety plans may be (unintentionally) designed such that they create circumstances that cause accidents.

In companies which decide to take the risk, it's likely its attitude about accidents is, "accidents just happen; there's nothing we can do about them." Of course, that's an unacceptable notion in any effective safety culture. Employers with a healthful attitude about accidents consider them to be "inexcusable," and demand hazards be corrected before they cause an accident.

3. Companies that have healthful attitudes consider accidents _____.

a. to be just the cost of doing business
b. as unavoidable
c. to be inexcusable
d. as beyond their control

Old Theory - Worker Error

Employee wearing a safety vest and hard hat and pointing to his head
If he just had common sense.

Old thinking about the causes of accidents assumes that the worker lacks common sense or makes a choice to work in an unsafe manner.

It implies that there are no outside forces acting upon the worker influencing his actions and that there are simple reasons for the accident. Old thinking considers accidents as solely resulting from worker error: A lack of "common sense." Actually, common sense, is an invalid concept. In reality, no one has common sense. Rather, we each develop a unique and hopefully "good sense" based on individual experience and education.

  • When we assume common sense is a valid concept, it allows us to more easily place blame for accidents squarely on the shoulders of the employee.
  • The Common sense excuse for accidents infers the employee is "the problem." To prevent accidents, the employee must work more safely.
  • Thinking that accidents are due to a lack of common sense results in short-term fixes that are inefficient, ineffective, and in the long run more expensive to implement and maintain.

4. Outdated causation theory assumes accident are caused solely by _____.

a. a lack of training
b. a lack of common sense
c. worker error
d. a lack of careful planning

New Theory - Systems Approach

A chart showing the different elemenst of a health and safety system
Assume the system needs fixing.
(Click to enlarge)

The systems approach takes into account the dynamics of multiple variables that interact within the overall safety management system.

  • It assumes accidents are due to defects in the safety management system.
  • People are only one part of a complex system composed of many complicated processes.
  • Accidents are the result of multiple causes or defects in the system.
  • It becomes the investigator's job to uncover the root causes (defects) in the system.
  • Fixing the system, not the blame, is the heart of the investigation.
  • To prevent accidents, the system must work more safely.
  • This line of thinking results in long-term fixes that are actually less expensive to implement and maintain.

5. In the systems approach, accidents are assumed to be caused by _____.

a. a lack of common sense
b. safety management system defects
c. defects human behavior
d. hazardous conditions inherent in the workplace

Why Conduct the Accident Investigation (AI)

One employee pointing a finger at another employee
You're guilty!

Why should you conduct an accident "investigation"? The answer to this question is key to the success of the entire AI process. Here's an important principle to understand:

To determine the purpose of a process, look at the final "output" of that process.

What does that mean? It means that to understand what the purpose of the accident investigation process is, you've got to look at the findings in the final report. So, let's contrast the findings in an OSHA AI report with what should be the findings in your AI report.

Why OSHA Conducts an Accident Investigation

As you are surely aware, OSHA conducts many accident investigations each year. You can review accident summaries at the OSHA Fatality and Catastrophe Investigation Summaries webpage.

Remember, the findings in an investigation report is the output of the investigation process, so let's take a look at the sample given in OSHA Instruction CPL 2.113, Appendix C:

Findings of the Investigation Report
MEMORANDUM FOR: Regional Administrator
FROM: Area Director
SUBJECT: Notification of Results of Fatality

The following information supplements the OSHA-170, regarding investigation of the accident at _____ Company, Inc.

Proposed Action: (The output!) Issue citations for serious and other violations of machine guarding, open floor holes, hazard communication and recordkeeping with a penalty total of $5,475. A 5(a)(1) letter outlining the hazards to be corrected which were not clearly addressed by 29 CFR 1928 Safety and Health Standards for agriculture and for which other OSHA Standards are not applicable will also be mailed to the company.

As you can see, the output was a recommendation to cite and fine the employer. The message in the above OSHA report is that, as required by the OSHA Act of 1970, OSHA conducts accident investigations to primarily determine if the employer violated OSHA standards. OSHA establishes employer liability, places blame, and administers "penalties" (punishment). This is OSHA's mandate:Establish liability and issue penalties as appropriate.

This is not your organization's mandate.

6. Where do you look to better understand the purpose of an accident investigation?

a. The purpose statement
b. The investigator's statement
c. The OSHA requirements
d. The investigation's final report

Investigate & Analyze to Fix the System... Not the Blame

Workers speaking to each other and reviewing a checklist
Work together to fix the system.

Unfortunately, some employers believe that the investigation process ends once the blame has been established. Here's the problem with that belief:

Once the purpose of the analysis process has been achieved, analysis stops.

When employers investigate to place blame, analysis stops and the employer does not continue an effective analysis process to fix root causes in the safety management system.

According to OSHA's Safety & Health Program Management Guidelines, the employer's primary purpose for investigating accidents is primarily, "so that their causes and means for preventing repetitions are identified."

OSHA goes on to say this about the investigation process:
"Although a first look may suggest that 'employee error' is a major factor, it is rarely sufficient to stop there. Even when an employee has disobeyed a required work practice, it is critical to ask, "Why?" A thorough analysis will generally reveal a number of deeper factors, which permitted or even encouraged an employee's action. Such factors may include a supervisor's allowing or pressuring the employee to take short cuts in the interest of production, inadequate equipment, or a work practice which is difficult for the employee to carry out safely. An effective analysis will identify actions to address each of the causal factors in an accident or 'near miss' incident."

Bottom line. The output of the employer's accident investigation process should not end with merely identifying violations of employer safety rules. The end product should identify the root causes: the safety management system weaknesses. In the most effective employer accident investigations, the question of liability (fault, blame) should be addressed only if an honest post-investigation evaluation concludes that no safety management system weaknesses contributed to the accident.

7. The end product of an accident investigation should identify the _____.

a. surface causes
b. root causes
c. primary causes
d. actual causes

Effective Accident Investigation Programs

An effective accident investigation program will be guided by standard written procedures. It's important to make sure procedures are clearly stated and easy to follow in a step-by-step fashion. An effective program will include the following:

  • A team of at least two investigators conduct the investigation. Two heads usually work better than one, especially when gathering and analyzing material facts about the accident.
  • Accident investigators are properly trained on accident investigation techniques and procedures.
  • The accident investigation is perceived as separate from potential disciplinary procedures resulting from the accident. The purpose of the accident investigation is to determine the facts, not the blame. Accident investigators must be able to objectively state that they are conducting the investigation only to determine what happened.
  • The accident investigation report is written and makes sure surface causes and root causes of accidents are addressed. Most accident reports are ineffective precisely because they neglect to uncover the underlying reasons or factors that contribute to the accident.
  • The accident investigation report makes recommendations to (1) correct hazardous conditions and unsafe work practices, and (2) improve underlying SMS weaknesses.
  • Surface causes for the accidents are corrected on the spot or as soon as possible. Long-term improvements in the safety and health system (SMS) are completed in a timely manner to make sure related surface causes do not reappear.
  • The accident investigation report will not place blame or include a recommendation for discipline. Discipline is a separate issue properly addressed by management/human resources only if contributing root causes have not been uncovered.
  • Follow-up procedures to make sure short-term corrective actions and long-term SMS improvements are completed.
  • An annual review of accident reports. Properly trained employees evaluate accident reports for consistency and quality. They verify that responsible persons correct surface/root causes are identified and that corrective actions/improvements completed.
  • Safety personnel annually review and evaluate the investigation program.
  • Information about the types of accidents, locations, trends, etc., is analyzed to improve investigations and prevent future accidents..

8. What is a characteristic of an effective accident investigation program?

a. Surface causes are corrected on the spot
b. They usually result in some form of discipline
c. Only third-party investigators are used
d. The focus is on determining liability

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.

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