An Accident: Investigation in Action

Thousands of accidents occur in the electrical construction industry each year. Accidents are defined as “an unplanned event that results in personal injury or property damage.” Their severity ranges from minor injury and minimal property damage to million-dollar losses and fatalities. It is often the minor accidents left unchecked that lead to a catastrophic event. In order to prevent future accidents, a thorough accident investigation must occur.

A case in point involves a 34-year old electrician who died from a 12-foot fall from a scaffold. The company had been in business for 70 years and employed 250 workers. It had been contracted to install the electrical system in a new shopping mall under construction. They were on the site four months when the incident occurred.

To understand the steps taken in an accident investigation, it is necessary to recognize that every accident involves a series of events, and the investigation determines the levels of cause by looking at each one of those events. Basically, an accident results when a person or object absorbs more energy or hazardous material than it can stand. Using our fatality as an example, the absorption of energy by the victim from the impact with the floor resulted in death. Although this may sound rather clinical, it helps to put the investigation in an objective perspective. Remember, the concept is to collect and analyze facts to prevent future accidents.

The fall and impact are the direct cause. However, a series of events led to the fall. These events were based on underlying motivators or causes. For starters, an unsafe act or condition was allowed. This is a symptom of poor company policies, neglected environmental factors and/or a compromised safety culture. With this in mind we can look at the investigation procedures.

A set number of investigative steps has not been established. Although experts generally agree on what needs to be done, their grouping and classification of the actions varies. The categorization used here will be 1. Collect the Facts, 2. Analyze the Data and Determine the Cause and 3. Prepare a Report with Corrective Actions.

Collecting the facts

The number and accuracy of facts associated with the accident is critical. Steps should be taken to secure the site and all applicable data sources. It is helpful if the tasks are distributed among a team. Inspect the site. Take photographs and create sketches. Record all applicable physical conditions including weather conditions, hazardous energy or substance levels, equipment conditions, etc. Check records. Look at accident records, equipment maintenance logs, company safety programs and policies. Especially note any abnormalities.

In this accident, the victim was using a mobile aluminum tubular-frame scaffold to access the 22-foot-high ceiling of a steel-beam frame structure. The floor was flat level concrete. The scaffold was three tiers high. Each tier measured 4 feet wide by 8 feet long by 6 feet high. The second tier was in place with the bottom section for the third tier across its top. Outriggers were being use and the casters in the lock position. No abnormalities in the equipment or maintenance records were noted.

With respect to company records and policies, unfortunately no reference was made to previous accident records to determine any patterns. However, employment records showed that the victim had been hired two days before the accident. The company policy was to distribute a handbook with company safety rules to new employees. Other training included on-the-job training and weekly tailgate meetings. The job superintendent was responsible for safety.

To determine the events on site and delve deeper into adherence to policies and company culture, interviews are critical. They should be performed as soon as possible following the accident. Understand that many factors affect testimony. An accident is a traumatic experience. The proximity of the observer to the accident, their observation skills, whether they feel they have a vested interest in the outcome of the investigation, and their emotional state will affect their testimony.

Locate the position of the witnesses on a master diagram. Arrange for a convenient time and place to interview the witnesses and victim (if available) individually. Identify the qualifications (name address occupation, training, years experience, etc.) of each. Explain the purpose of the accident investigation as accident prevention. Word questions carefully. Allow interviewees to speak freely. Use sketches and diagrams to help them, but do not put words in their mouths. On your records, note and distinguish hearsay from fact. If possible, have the interviewee sign a copy of their statement.

Only one witness, an electrician’s helper was in the proximity of the accident. He stated that he and the victim had started work at 7 a.m. and dismantled and moved the scaffold at 8 a.m. They began to reassemble the scaffold at a new location 30 feet from its original position. When the victim began to move the two 8-foot floorboards from the second tier to the third, the helper went to retrieve another section of the scaffold from the previous location. He returned to find the victim face down on the concrete floor, bleeding profusely from the nose and mouth.

The supervisor notified and called the superintendent in the company trailer by radio. Emergency medical services (EMS) were called while other employees began cardio pulmonary resuscitation. EMS arrived 15 minutes later and transported the victim to the hospital, where he was pronounced dead by the attending physician.

The final component of your data collection is to get the information relative to the conditions and procedures, which are appropriate for the operation. Research safety regulations, consensus standards and other recommended safety practices. If any chemical or physical laws are applicable to the event be sure to identify them. For example, in the case of a fire ignition properties of the substance are important. The Occupational Safety and Health Administration (OSHA) and American National Standard Institute rules are needed as reference for the scaffold accident.

The next step

Once the data has been collected, it must be analyzed to determine a cause. The recommended method of analysis is to identify changes from the norm, which may have led to the accident. First identify the problem: The victim fell. Place the events leading to the problem in sequence. The victim was hired and two days later was on the job dismantling and erecting a scaffold with only a helper in the vicinity. As much as possible, review the details.

Next identify the norm. OSHA standards require employees be trained by a competent person on the erection and dismantling of a scaffold. Where feasible, at heights of 10 feet or higher, fall protection must be used during erection and dismantling of scaffolds. Compare the norm to the problem and note any abnormalities. Determine the possible affect of the abnormality or change from norm. Propose alternate procedures and the affect they might have on the outcome. Select possible causes and identify those that most likely resulted in the accident.

The changes to norm in the scaffold accident in question were the lack of training by a competent person and fall protection. Consider whether the presence of a competent person during the erection could have prevented the fall. If the victim had been wearing appropriate fall protection, what would have occurred when the fall did occur. Tracing these events back further, the questions arise—Why wasn’t a competent person on site? Why wasn’t fall protection in place? Is there enforcement of safety rules?

A proposed alternate sequence of events would include the following. All employees receive an employee safety handbook and hazard specific training as needed. The job superintendent who is responsible for safety shall serve as the competent person, have the experience and training as needed to serve as the competent person on site, inspect and enforce workplace rules and be present during any hazardous operation that requires the competent person. Management will support safety. Time, materials and funding will be made available as needed to insure employees are protected.

The report

The results of the investigation are useless unless they are communicated to management and other employees. It should provide the information they need to prevent recurrence of a similar accident. Be sure procedures are in place to share this information. Management should review the content. The information pertinent to making the appropriate correction should be included in safety talks or other training, which will help employees. Names should be withheld when used for training purposes.

The following offers a basic structure for your report to management. First, provide the background needed. Who was involved? Identify the victim, operating personnel and witnesses. Describe the location and environment where the accident happened.

Account for the accident. Describe the events, damage which resulted and the agent(s) involved. These include any hazardous energy (electricity, heat, etc.) or materials (falling objects, chemicals, etc.)

Next, offer a discussion of how and why the accident occurred. Begin with the direct or immediate causes. For example, the lack of scaffold training and fall protection would be on the top of the list for the scaffold accident. This would be followed by a description of the underlying causes. Underlying causes explain why the immediate causes are allowed to occur.

Complete the report by offering recommended corrective actions. These must target the causes identified in the discussion of how and why the accident occurred.

One hopes they will never have to conduct an accident investigation. But, if and when an accident occurs a thorough investigation with a complete report can do much to prevent recurrence. It cannot be emphasized enough the need to communicate this information to employees and implement the corrections recorded in the report. Be sure to present the information in a manner that protects the privacy of employees involved so that they can focus on the recommendations, appreciate the investigation as an accident prevention tool and dismiss the concept of blame.

If you would like to receive more samples of accident investigations conducted by the National Institute of Health, feel free to e-mail me at I will e-mail you copies of two other investigations involving electricians. EC

O’CONNOR is with Intec, a safety consulting, training and publishing firm that offers on-site assistance and produces manuals, training videos and software for contractors. Based in Waverly, Pa., he can be reached at 607.624.7159 or


About the Author

Joe O'Connor

Freelance Writer
Joe O'Connor is with Intec, a safety consulting, training and publishing firm that offers on-site assistance and produces manuals, training videos and software for contractors. Based in Waverly, Pa., he can be reached at 607.624.7159 or joconnor@inte...

Stay Informed Join our Newsletter

Having trouble finding time to sit down with the latest issue of
ELECTRICAL CONTRACTOR? Don't worry, we'll come to you.