Safety Leader

What Went Wrong? Reviewing an electrocution accident from an aerial lift

Aerial lift trucks can be dangerous if not properly maintained and operated.

Courtesy of Wes Wheeler
Published On
Aug 12, 2021

The use of aerial lift trucks can be extremely beneficial, but they can be dangerous if not properly maintained and operated. When working with an aerial lift truck, a competent person should always conduct a daily inspection at the start of each shift to identify any abnormalities or wear and tear. When conducting a daily inspection, it is important that all department of transportation requirements are satisfied. 

Components that should be evaluated include attachment welds between actuating cylinders and booms or pedestals; pivot pins for security of their locking devices; exposed cables, sheaves, and leveling devices for wear and security of attachment; the hydraulic system for leaks and wear; lubrication of the boom; the boom and basket for cracks or abrasions; operation of the boom from ground controls through one complete cycle; and any other inspections recommended by the manufacturer. Any and all defects should be reported to a supervisor and must be corrected before use. 

When operating an aerial lift, the equipment should be given time to warm up and be used only by authorized, properly trained employees. It is imperative to adhere to all weight limits for the boom and basket and avoid shock loading or sudden stops and starts. 

Most aerial trucks have upper and lower operational controls. However, the lower controls should never be used unless it’s been cleared with the individual working in the bucket or basket. 

All employees working from a bucket should avoid standing or sitting on the top or edge of the bucket or basket and must wear approved fall protection at all times. Safety lanyards should never be attached to an adjacent pole or object and climbers should not be worn while in the basket. The worker’s feet should always stay on the floor while in the basket, as well. 

An aerial lift should never be moved while extended and no person should ride in a bucket or basket from one location to another. When working in an aerial lift, the ground crew and the worker in the bucket need to ensure that the equipment’s emergency brake is on and that wheel chocks and outriggers with outrigger pads are used at all times. 

Using an aerial lift over a street or highway is not recommended. However, if there is no alternative, employers can enlist the support of local law enforcement for additional protection. If there are two workers in an aerial lift bucket or basket, only one should be designated to operate directional controls. When work is being conducted near energized lines or equipment, workers should wear rubber protective equipment. This includes those working on the ground near the lift. Finally, workers on the ground must avoid contact with truck bodies or grounding assemblies. 

Results of the investigation

The Tennessee Occupational Safety and Health Administration (TOSHA), Nashville, responded to the fatality and conducted an accident investigation. The employer was found to be in violation of federal regulations and received two citations. 

The first was associated with safe use of an aerial lift. According to OSHA 29 CFR 1910.67(c)(2)(viii), “An aerial lift truck may not be moved when the boom is elevated in a working position with men in the basket, except for equipment which is specifically designed for this type of operation in accordance with the provisions of paragraphs (b)(1) and (b)(2) of this section.” 

The second citation was for a violation of an electrical safety standard. OSHA 29 CFR 1910.333(c)(3)(i)(A)(1), addresses selection and use of work practices. More specifically it establishes minimum approach distances for working on or near exposed energized parts. In this case, for voltages to ground 50 kilovolts (kV) or below, the minimum clearance needed to be at least 10 feet.

In addition to the OSHA citations, state inspectors found that the employer was in violation of state regulations pertaining to recordkeeping and reporting. As a result, the employer was issued three more citations. These regulations match up with federal OSHA recordkeeping requirements.

The first was for failure to comply with Tennessee Department of Labor and Workforce Development (TDLWD) Rule 800-01-03-.03(27)(A), which indicates, “You must use OSHA 300, 300-A, and 301 forms, or equivalent forms, for recordable injuries and illnesses. The OSHA 300 form is called the Log of Work-Related Injuries and Illnesses, the 300-A is the Summary of Work-Related Injuries and Illnesses, and the OSHA 301 form is called the Injury and Illness Incident Report.”

Additionally, the employer was cited for TDLWD Rule 800-01-03-.05(1)(A)1 and TDLWD Rule 800-01-03-.05(1)(A) 2, Reporting Fatality, Injury and Illness Information, which states, “Fatalities and multiple hospitalization incidents must be reported to TOSHA. (a) Basic requirement. 1. Within eight (8) hours after the death of any employee as a result of a work-­related incident, you must report the fatality to the TOSHA Division of the Tennessee Department of Labor and Workforce Development. 2. Within twenty-four (24) hours after the in-patient hospitalization of one or more employees or an employee’s amputation or an employee’s loss of an eye, as a result of a work-related incident, you must report the in-­­patient hospitalization, amputation, or loss of an eye to TOSHA.”

Although not cited as a violation in this accident, employers should conduct a hazard assessment to identify potential dangers and develop and implement appropriate control measures for them. This should be done by a competent person before any work is started. In this incident, the job site had identifiable hazards in the form of overhead power lines in proximity to where the aerial lift functionality test was being performed.

Employers should also abide by existing OSHA regulations and safe work practices pertaining to the operation of aerial lifts near overhead power lines and take the appropriate steps to de-energize or insulate power lines before work begins. OSHA Standard 29 CFR 1926.416b, 1 states, “No employer shall permit an employee to work in such proximity to any part of an electric power circuit that the employee could contact (direct or indirect) the electric power circuit in the course of work, unless the employee is protected against electric shock by de-energizing the circuit and grounding it or by guarding it effectively by insulation or other means.” OSHA 29 CFR 1926.550(a) (15)3 requires that the minimum clearance between electrical lines rated 50 kV or below and any part of a crane/equipment or load be 10 feet, unless the electrical lines have been “de-energized and visibly grounded” or insulating barriers have been erected “to prevent physical contact with the lines, equipment or machines.” 

If it is necessary to work closer than 10 feet (horizontal distance) from an energized line, the employer must comply with the 10-foot clearance standard. 

Employers should also ensure that when working near a high-voltage overhead power line, and visibility can be obstructed or clearances difficult to determine, an observer on the ground is used to help the operator maintain the required clearance. The aerial lift, in this accident, was in a position that the operator had their back to the power line. If an observer had been helping, they would have immediately alerted the operator of the bucket’s proximity or contact with the power line, and the accident could have been prevented altogether. This is required by OSHA Standard 29 CFR 1926.550(a)(15)(iv)4, which states, “A person shall be designated to observe clearance of the equipment and give timely warning for all operations where it is difficult for the operator to maintain the desired clearance by visual means.”

Additionally, employers should create, implement, and enforce a comprehensive written safety program. The program should include training in hazard recognition and the avoidance of unsafe conditions for all workers. A written training plan for all employees on electric utility operations can be helpful, too. 

According to National Institute of Occupational Safety and Health, Fatality Assessment and Control Evaluation—2005-02, “Certain types of site-specific training (i.e., training in hazards associated with the installation of support anchors with equipment/boom trucks in proximity to overhead power lines) must be conducted and documented. This training should be given by a person who has the knowledge, training, and experience necessary to train workers and could consist of a combination of formal instruction, i.e., lecture, discussion, interactive computer learning, videotape, written material, practical training (demonstrations performed by the trainer and practical exercises performed by the trainee), and evaluation of worker performance in the workplace.” 

The dangers associated with aerial lifts and energized lines or equipment are paramount in hazard abatement and preventing future accidents. 

About the Author

Tom O'Connor

Safety Columnist

Tom O'Connor is safety and regulatory affairs manager for Intec, a safety consulting, training and publishing firm that offers on-site assistance and produces manuals, training videos and software for contractors. Reach him at toconnor@intecweb.com.

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