Environmental, Health and Safety Services

General Requirements

Facts and Physical Data

Begin gathering information and data as soon as you are notified of the incident. After the victim has received emergency care, begin filling out the "Notification Record". This form will help you to begin recording data, and remind you of actions (if applicable) to be taken immediately after the incident.


Before objects are moved, cleaned, or removed, the investigator should record the scene as it was at the time of the incident.

Take Photos!

Once the injured has been removed from the scene, take several pictures of the incident area from different angles and distances to preserve the scene for later review. Take a shot of the general area, a closer shot of the object involved in the incident, and a close up shot of any detail which might be important. Keep in mind that the pictures you take will help you to identify site orientation problems, people or control panel positioning issues, and work flow patterns. It may be helpful to place an object, such as a ruler or pencil, of known size into the picture to show proportion. And, you should know how to use the camera beforehand; learning to use it during a critical incident may cost you valuable evidence.

Sketch the Layout

Using graph paper, make a sketch of the objects in the area and their locations. Use a tape measure to note the actual distances between objects for exact reference. Remember to include vertical measurements as well as horizontal. Check the entire area (ceiling, walls, equipment, and floor) for signs of damage or disturbance, or which may in any way be related to the incident. Be thorough!

Document Conditions

Slips and trips are one of the most common incidents at Virginia Tech, and therefore an accident investigation is always recommended. As you are gathering data at the scene, if a slip or trip hazard is suspected, use the Slip and Trip Worksheet to record conditions and help identify contributing and root causes.

Sequence of Events

You will also want to begin to establish the sequence of events leading up to the incident. Use the Sequence of Events and Contributing Causes form to identify the key events involved. Begin by writing the incident in the star. Work your way backwards to fill in events leading up to the incident in the rectangles based on witness statements and interviews. This form can be referred to later when you are ready to determine contributing causes and identify the root cause.


It will be necessary to talk to people who were involved in the incident, a witness to the incident, or who were involved in the reporting and response to the incident. First, identify such persons and have them write their account of what happened as soon as possible. The more time people have to discuss the incident, the more their account may be influenced by other's accounts and memory retention. Interview witnesses separately. The Incident Statement form is used to record witness, supervisor, and the injured employee accounts. You will need to have several copies on hand to accommodate all personnel involved.

Employee Statement

As soon as feasibly possible, have the injured/ill employee(s) complete an Incident Statement regarding the circumstances leading up to the accident and what happened that resulted in the injury/illness. The employee should state in his/her own words what happened. Explain that this type of paperwork is routine in accident investigations.


It is important to have all witnesses to the accident complete an Incident Statement so that information can be reviewed later for consistencies in each account. The witnesses should state in their own words what they witnessed, and be encouraged to include as much detail as possible, whether they feel it is relevant or not. Explain that this type of paperwork is routine in accident investigations.


Often the supervisor is the first person notified of an incident. He or she should complete an Incident Statement regarding details of notification and actions taken. The supervisor may also be able to provide information regarding earlier behavior, activities of the person(s) involved in the incident, or related personnel issues.

After all statements have been taken, the investigator should review them for consistencies/inconsistencies and common themes or unique information. This will help the investigator determine who will need a follow up interview and what questions will need to be asked. Use the Interview Questions form to write down what questions will be asked for the face-to-face interview. Not all questions must be written down since many will arise based on what information is provided at the time of the interview; however, all responses should be documented. It you are having difficulty getting information from witnesses, here are some guidelines.


Although there is considerable paperwork to be filled out during an accident investigation, there may be existing documentation that you may need to review to determine what policies, practices, protocols, training, and assessments are already in place. Ask the supervisor to show you any of the following, as appropriate.

  • Written policies related to the activities of personnel
  • Related health and safety programs
  • Hazard assessment forms or monitoring results
  • Training records
  • Disciplinary action or counseling of the employee injured
  • Operator's manual if machinery or equipment was involved
  • Written standard operating procedures (SOP)

You will also need to review any university health and safety programs or regulatory standards to determine if established requirements were in effect and followed. EHSS can provide assistance with this area.


Parts involved in an incident can be any material, machine, equipment, or structure involved. Identify "parts" to be further investigated and use the Parts Worksheet to identify areas of concern. For complicated systems, technical experts, manufacturer representatives, or inspectors may need to be involved in the review.

The first priority is to preserve the evidence. Do not move objects or remove components until interviews and pictures have been taken and all parties that will be involved in the investigation are present and agree to proceed. In serious incidences involving manufactured products, parts or components may be taken as evidence for legal purposes, and a chain of custody may be required to prove that parts and components have not been tampered with. You must notify EHSS of investigations involving outside manufacturers, inspectors, or other representatives. Follow these recommendations for evaluating parts.

Data Analysis

The purpose of analyzing the data is to identify all of the causes for which a corrective action is possible. Management must review and select the corrective action(s) most likely to be effective (i.e. the root cause), beneficial (i.e. contributing causes), cost-effective, and acceptable, and implement them.

There are a variety of incident investigation and analysis techniques available, some of which are more complicated than others and may require specialized training. There are benefits and limitations associated with every method. This program provides techniques that most investigators can use immediately.

Sequence of Events and Contributing Causes

You may have already begun to fill out the Sequence of Events and Contributing Causes flow chart. If the incident is minor and simple, this tool may be all you need to complete the investigation. Now you will need to consider the event in each rectangle and ask if there was some reason (i.e. contributing cause) which caused the event to be present or to occur. If additional pages are needed, the diamond is the connecting point to other pages. As you fill it in, you will begin to see where you need more information and what questions will need to be answered during interviews and analysis.

Once all of the events and conditions have been filled it, review the chart to identify the event or condition which could have prevented the incident had it been controlled or did not occur. There may be more than one causal factor. Further investigation of events or conditions may be necessary.

Fishbone Diagram

For more complicated incidents involving various elements, it may be helpful to use the Fishbone Diagram or the Guide for Identifying Causal Factors and Corrective Actions to identify ideas regarding contributing causes. Both tools guide you through the process of considering various aspects and causes by providing categories to brainstorm on or common questions to ask.

To use the Fishbone Diagram, first state the problem in the form of a "why" question to help stimulate ideas. The investigator or team should agree on the statement of the problem. The "bones" or branches of the diagram are categories that can be changed or modified to suit your subject matter. Suggested categories include:

  • People
  • Policies
  • Procedures
  • Processes
  • Machinery
  • Materials
  • Environment (facilities, weather, noise, lighting, etc.)
  • Technology

Consider each category when brainstorming causes for the problem statement. Write the cause along the vertical line connected to the related category. The investigator or team should review the causes to determine which one(s) warrant further investigation.

Guide for Identifying Causal Factors and Corrective Actions

The Guide for Identifying Causal Factors and Corrective Actions is relatively self-explanatory, and also provides possible corrective actions to consider. Simply go through the list of questions in the "Causal Factors" column and identify all possible contributing causes. Once you have answered all of the questions, you may want to further investigate each causal factor to identify the root cause. Lastly, note the corrective action(s) to be taken in the last column.

Ergonomic Issues

Certain activities, such as lifting, carrying, pushing, pulling, or repetitive motion, may have been involved in the incident. The following worksheets can be useful in gathering certain information for further analysis. It is recommended that you consult with EHSS' Ergonomist for a complete and effective analysis where these activities are potentially contributing or root causes.

Behavior Analysis

Studies indicate that 90-95% of all incidents have a human performance causal factor. This is not to say that the person is at fault 90-95% of the time! It simply means that a person's behavior and attitudes, along with the culture of the workplace, are common elements which can influence or contribute to the cause of an incident. Where human performance is suspected as a contributing or causal factor, further investigation is warranted.

Begin by filling in the Behavior Analysis Chart. Start with the second column (i.e. the physical behavior that resulted in injury or illness). Next, investigate all possible things or events (i.e. antecedents) which may have triggered the behavior. Last, for each trigger or antecedent, evaluate the persons' perception of the consequences to identify areas that may need intervention or correction. This evaluation will involve three factors:

  • Significance - whether the person perceives the consequence as positive (+) or negative (-).
  • Timing - whether the person believes that the consequence will occur sooner (s) rather than later (l).
  • Consistency - whether the person perceives the consequence as certain (c) or uncertain (u).

Example: An employee was injured and sent to the hospital because he operated a chop saw without a guard.

Triggers (2)

Behavior (1)

Consequences (3)

Evaluation (4)

1. Needed to get the job done.

Operated chop saw without guard.

1. Save time and get job done.

+, s, c

2. Everyone else uses it that way.

2. Will fit in with others.

+, s, c

3. "It won't happen to me" attitude.

3. Gets the job done. Fit in.

+, s, c

4. Operating procedure was unclear.

4. Injury

-, l, u

Once the triggers and consequences have been identified and evaluated, you should use the Behavior Analysis Worksheet to determine why the triggers were present and why the consequences were perceived as they were. This will provide you with contributing causes, which can be reviewed to determine the root cause.

Root Cause(s)

5 Why

Once you've identified contributing causes and/or causal factors using one of the methods above, the next step involves investigating why they occurred and determining the root cause(s). (Note: It is now generally accepted that there may be more than one root cause to a problem.) Again, there are many methods for determining the root cause, and all have their limitations; however, one of the simplest methods is the "5 Why" technique. By repeatedly asking the question "why?" you can sort through the layers of symptoms that lead to the root cause.

To complete the "5 Why" method, write down the specific problem on the form (i.e. contributing cause, causal factor, or the incident itself) to help formalize and describe it. Next, ask why the problem happens and write the answer below the question . If the answer just provided doesn't adequately identifies the root problem, ask why again and write down that answer. Repeat this process until you have identified the root cause and the team is in agreement. Asking why five times is a good rule of thumb; however, you may only need to ask why three or four times (or six or seven) to get to the root of the problem.

Causal Factors & Root Causes Worksheet

Another convenient tool to use when identifying contributing and root causes is the Causal Factors & Root Causes Worksheet. This worksheet provides you with a list of common causes grouped by categories. After you have completed your data gathering and analysis, the possible causes can be checked off (on the left) and reviewed to identify contributing causes (check the box in the “CC” column) and the root cause(s) (check the box in the "Root" column).

Corrective and Preventative Action(s)

Depending on the situation, there may only be one corrective action identified to address the root cause, or there may be several corrective actions that need to be taken to address other root or contributing causes. The Corrective and Preventative Actions form can be used to list those causes which require additional action. Once the corrective or preventative action has been identified, it should be assigned a due date and a responsible person to coordinate completion. This form should be reviewed periodically to ensure progress and eventually close out the action item by filling in the completion date. At this point, the incident is considered "closed".