NIOSH Fatality Assessment and Control Evaluation (FACE) Program
Tower Construction Worker Dies Following 200 Foot Fall
From Radio Tower in Missouri
|Missouri FACE Report #98MO102
Released: May 13, 1999
On October 14, 1998, a 35-year-old male tower erector (victim) working for a tower erection company died after falling 200 feet while attached to the gin pole. The victim was part of a four-man crew working on the erection of a 400-foot, three-sided radio tower. The workers were in the process of extending the gin pole above the existing tower sections in preparation for raising the next section of tower. The victim had climbed to the top of the tower and set the jumper block in place with a one-quarter-inch sling wrapped over the tower section's top flange. This jumper block was then used to raise the gin pole into position. The victim then climbed down the tower and released the bridle and basket chokers supporting the weight of the gin pole on the tower. He then climbed from the tower and onto the base plate of the gin pole, using his positioning lanyards to tie himself off. A coworker operating the wench began lifting the gin pole into position with the victim attached. The sling cable supporting the weight of the gin pole and the victim failed causing them to fall to the ground. The victim was killed instantly upon impact with the ground.
The purpose of the FACE Program is to identify risk factors that contribute to worker injury and death, and to make recommendations to employers and individuals on how similar events can be avoided. From the information collected about this incident, the MO FACE investigator concluded that employers should:
instruct workers not to use the gin pole for ascent or decent during tower construction activities and continually stress and enforce to all employees the importance of following established safety rules and procedures at all times;
ensure that employees are trained in the proper selection and use of slings and chokers;
ensure that equipment is used in accordance with manufacturer's specifications;
ensure 100 percent fall protection while working on towers.
The MO FACE investigator was notified of an occupational fatality at a tower construction site in Missouri at 3:45 p.m. on October 14, 1998, approximately 40 minutes after the incident. At this time the county coroner requested immediate assistance from the MO FACE Program to assist in investigating the fatality incident. The MO FACE investigator arrived at the incident site at 5:30 p.m. The victim had been removed from the gin pole and placed in the Coroner's wagon. Local police and fire departments, as well as the county sheriff's department and the coroner remained on-site. The coworkers were released from the site and returned to their motel rooms.
The employer is a tower erection company who has been in business for 15 years and at the time of the incident employed 10 workers. The company had written safety rules and procedures in place for the tasks performed by the workers. According to the employer, the victim had received training that specifically addressed the hazards associated with the fatality.
The victim was hired as a tower erection crew foreman. He had worked for this employer approximately eight years prior to his current employment. This was his seventh day with the company and his third day on this project when the incident occurred. This was the company's first fatality incident.
The company contracted with a communications company to erect a 500-foot tower for a new radio antenna. The communications company was acting as the general contractor and had previously cleared the land, poured a concrete pad for the tower, poured slabs for the anchorage points, and erected a building to house the electronics and maintenance equipment. The tower sections to be erected were three sided and 20 feet in length constructed of galvanized tubular steel with flat angle iron collars. The week prior to the incident the company owner and crew went to the site and erected the first 120 feet of tower using a crane. After securing the tower with guy wires, they raised the 60-foot gin pole, weighing approximately 1,300 pounds, in position with the crane and attached it to the tower. The company owner and crew returned home for the weekend.
The Monday before the incident the work crew of four left the company's warehouse and drove work vehicles to the site. The crew consisted of the tower foreman (victim), a ground foreman and two coworkers/laborers. The ground foreman was experienced in the trade and had worked for the employer for more than one year. Coworker #1 had two months experience in tower construction, all with this employer, and this was coworker #2's first week on the job. The workers arrived on site about mid day and began setting up for the building process. The second day for this crew went well as they stacked three tower sections bringing the total height to 180 feet.
On the day of the incident the crew began to stack the next sections of tower. All appeared to be going well and the project was on schedule. The victim and coworker #1 were working on the tower while the ground foreman was operating the winch and coworker #2 was a ground man. The workers were in voice contact with each other using radio communication headsets. The victim was also providing on-the-job training to coworker #1 on the tower. This was this coworker's first experience in working from the tower.
The workers had built the tower height to 260 feet by approximately 2:00 p.m. At this time the foreman and coworker #1 were making preparations for positioning the gin pole and raising the next section. The victim had set the jumper block on the top of the tower attaching it with a one-quarter-inch wire rope sling. The hoist operator then took up the slack on the jump line and raised the gin pole up taking the pressure off of the bridle and basket chokers, which were supporting the weight of the pole. The chokers were removed and the pole was ready to be raised up to its next position. The victim then climbed off of the tower and onto the base of the gin pole, securing himself to the pole with his positioning lanyard and also a large shepherd's hook. The hoist operator then began raising the gin pole when the sling holding the jumper block failed causing the gin pole and the victim to fall. The victim was killed immediately upon impact with the ground, and the gin pole fell over to the side. No one else was injured.
The ground foreman and coworker #2 immediately came to the victim's aid but the severity of the injuries was obvious. The workers requested emergency services. Local police, sheriff's department, ambulance service and fire service all responded. The coroner was then notified and responded to the scene. After arriving at the scene and determining this incident was a work-related fatality, the coroner notified the MO FACE Program. The coworkers gave witness statements to the local law enforcement and they were released from the scene to return to their motel rooms. The scene was photographed and video taped by the local law enforcement and the victim was removed from the gin pole. The coroner, local law enforcement and fire and rescue stood by waiting for the MO FACE investigator to arrive.
Upon arrival the MO FACE investigator directed local police and sheriff's office to take some additional video and photographic documentation of the scene. He also collected victim information from the coroner. The employer was contacted by cellular phone and advised that the MO FACE investigator was on site and starting his investigation at the request of the county coroner's office. Also interviewed was the communications company's office manager who was representing them as the general contractor.
The MO FACE investigator then returned the next day continuing the investigation. He met with OSHA compliance officers assigned to investigate the incident and interviewed the coworkers and ground foreman. While on site the county deputy sheriff arrived and presented photographs taken on the day of the incident. OSHA and MO FACE investigator then traveled to the local police station where the videotape of the accident was reviewed. OSHA took custody of the sling cable that failed for forensic testing. The workers were released from the scene and returned to the company office. The MO FACE investigator then met with the company owner and collected information about his company, its safety program, and additional information about the incident.
CAUSE OF DEATH (top)
Massive Internal Injuries
RECOMMENDATIONS / DISCUSSION (top)
Recommendation # 1: Employers should instruct workers not to use the gin pole for ascent or decent during tower construction and continually stress and enforce to all employees the importance of following established safety rules and procedures at all times.
Discussion: In this incident, the victim climbed onto and tied off to the gin pole from the tower to ascend up the tower. According to the employer, this method of ascent or descent is not approved and they had provided training and instruction to this effect. Additionally, hoist operators should not perform any hoist activity when a coworker is inappropriately tied off to the tower, gin pole, or the hoist cable. According to the National Association of Tower Erectors, Interim Compliance Guidelines for Employee Access by Hoist During Communication Tower Construction Activities, section 15,c., "the hoist operator shall be responsible for those operations under his/her direct control. Whenever there is any doubt as to safety, the operator shall have the authority to stop and refuse to handle any load until safety has been assured." Employers should establish a "No Rides" policy for tower construction. Workers should never be allowed to ride equipment or materials up or down the tower.
Recommendation # 2: Employers should ensure that employees are trained in the proper selection and use of slings and chokers.
Discussion: In this incident the sling used to attach the jumper block to the tower was not of the appropriate size or strength for the application. Also, it appears the sling was wrapped around the angle iron flange of the tower section. According to the employer, OSHA had the choker examined by a qualified engineering firm and reported that it most likely failed due to it was undersized for the downward weight of the gin pole and that it was wrapped over the sharp edge of the angle iron flange.
Employees should be trained in the proper selection of attachment points used when lifting and supporting heavy objects. Slings and chokers should not be wrapped over sharp metal edges. When no other attachment point exists, other methods of attachment should be explored to prevent sling and choker failure.
Recommendation #3: Employers should ensure that equipment is used in accordance with manufacturer's specification.
Discussion: The hoist use in this incident was not rated for transport of personnel, and warning labels on the hoist stated that the winches were not intended for use in lifting or moving persons. Though the employer's policy is not to allow workers to ride equipment up and down the tower face, employers need to ensure their equipment is certified to be used as a personnel lift before operating it in that manner. Equipment should only be used as rated by the manufacturer in accordance with 29 CFR 1926.53 (a) (4) which states, "all base-mounted drum hoists in use shall meet the applicable requirements for design, construction, installation, testing, inspection, maintenance, and operations, as prescribed by the manufacturer."
Recommendation #4 Employers should ensure 100 percent fall protection while working on towers.
Discussion: In this incident the victim and coworker #1 were using fall protection consisting of a full-body harness with positioning D-Rings and short lanyards and hooks. The victim practiced 100 percent tie off when attaching himself to the gin pole. It appeared the victim had tied off to the gin pole twice, once with what appeared to be a shepherd's hook and once with a short nylon lanyard.
Employers should instruct tower workers to maintain 100 percent fall protection during tower construction. One hundred percent fall protection is defined as follows: every employee at risk of fall from work levels over six feet above the ground or working surface must be protected by some integral fall arrest system. This applies to ascending, descending, moving point to point, or to any construction or alteration work activity conducted at an elevated work station. Employers should also require a minimum of three-point contact (two hands, one foot or two feet, one hand) at all times.
Traditional fall protection for this job is more effective when the employee is stationary and tied onto the structure. It is recommended that other methods of fall protection be used that protect employees while they are moving as well as stationary. Employees should be equipped with two lanyards so that while moving from point to point, one lanyard will be connected to the tower at all times. Additionally, a lifeline system or cable safety climb device attached to the highest point of the tower leg provides a tie-off point for the employee to hook onto, and provides fall protection coverage at all times. For a tower leg or similar vertical structure, the employee should wear a fall arrester (e.g., rope grab) attached to the lifeline, enabling the worker to move freely without interference until a free fall is detected. Though the fatality in this incident was not due to a lack of fall protection, it is an issue with many of the tower construction-related deaths. Employers should ensure that every effort is made to implement and enforce a 100 percent fall protection program.
The Missouri Department of Health, in co-operation with the National Institute for Occupational Safety and Health (NIOSH), is conducting a research project on work-related fatalities in Missouri. The goal of this project, known as the Missouri Occupational Fatality Assessment and Control Evaluation Program (MO FACE), is to show a measurable reduction in traumatic occupational fatalities in the state of Missouri. This goal is being met by identifying causal and risk factors that contribute to work-related fatalities. Identifying these factors will enable more effective intervention strategies to be developed and implemented by employers and employees. This project does not determine fault or legal liability associated with a fatal incident or with current regulations. All MO FACE data will be reported to NIOSH for trend analysis on a national basis. This will help NIOSH provide employers with effective recommendations for injury prevention. All personal and company identifiers are removed from all reports sent to NIOSH to protect the confidentiality of those who voluntarily participate with the program.