Fatality Assessment and Control Evaluation (FACE) Program
Hispanic Carpenter’s Helper Dies after Crane Boom Fell on Him during Disassembly - North Carolina
On January 30, 2006, a 37-year-old male Hispanic carpenter’s helper (the victim) was fatally injured while assisting in disassembling a lattice boom on a truck-mounted crane. The crane operator and the victim were working together removing pins that secured the 40-foot center section to the base boom section. After dislodging the second bottom pin, the boom hinged on the top two pins and fell on the victim’s back pinning him to the ground. The supervisor summoned a coworker who contacted 911 and company managers immediately. A hydraulic crane located nearby was brought to the site and used to lift the boom off of the victim. Approximately 5 minutes after receiving the 911 call, emergency medical services (EMS) personnel arrived and extricated the victim. They attempted resuscitation but were unsuccessful. EMS personnel notified the EMS medical director of the victim’s condition, and resuscitation efforts were suspended. The victim was transported to the hospital where he was pronounced dead about 45 minutes after the incident.
On January 30, 2006, a 37-year-old male Hispanic carpenter helper (the victim) was fatally injured while assisting in disassembling a truck-mounted crane boom at a bridge construction site. On February 16, 2006, the North Carolina Occupational Safety and Health Administration (NCOSHA) office notified the National Institute for Occupational Safety and Health (NIOSH), Division of Safety Research (DSR), of the incident. On April 11 and 13, 2006, a DSR safety and occupational health specialist met with the NCOSHA compliance officer assigned to the incident. The DSR safety and occupational health specialist traveled to the company headquarters on April 12, 2006, and met with the company’s managers and reviewed training records. The DSR safety and occupational health specialist traveled to the incident site with the company’s safety manager and interviewed the crane operator, a coworker who witnessed the incident, the bridge superintendent and the project manager. The incident site and the crane were examined. The police report and medical examiner’s report were reviewed. The cause of death was obtained from the medical examiner’s report.
Note: The victim’s age recorded on company records and based on documentation provided by the victim at the time he was hired, was 48 years old. The NCOSHA compliance investigation record reflects that age. During the course of the medical examiner’s investigation, a close personal associate of the victim provided official documentation that indicated that the victim was 37 years old at the time of the incident, therefore age 37 was used for the victim’s age in this report.
Safety Program and Training
This was the employer’s first fatality in its Bridge Construction Division. There had been 5 fatalities in its Highway Construction Division over the company’s 54 years of operation; none involving cranes.
The incident site was a bridge overpass, part of a larger state-funded highway construction project that began August 4, 2005, and was to be completed by July 1, 2007. A truck-mounted crane with an 80-foot lattice boom (Photo1) had been used to set approximately 20 girders which spanned the southbound lanes of the bridge. The next task, unloading and placing concrete decking over the girders, required a longer boom. The company had a 30-foot and a 40- foot lattice boom section lying on the ground next to the truck mounted crane. These sections were to be assembled and then added to the existing 80-foot boom (which was comprised of a 20-foot end boom section, 40-foot center section, and a 20-foot lower boom section). The boom on the truck-mounted crane was to be disassembled between the 40-foot center section and the 20-foot lower boom section. After the 70-foot section was inserted, the overall boom length was to be 150 feet.
Work began at about 7 a.m. on the day of the incident. The crew was told that a truck carrying concrete bridge panel decking was on its way to the site and the decking needed to be offloaded and placed on the bridge that afternoon. According to the crane operator, there was a sense of urgency to get the crane ready for the day’s work. The site superintendent, crane operator, and two carpenter’s helpers assembled the 70-foot section of boom. After the boom section was assembled, the site superintendent walked about 100 feet away and helped unload materials for the next phase of the job.
The crane operator was left in charge of the crane assembly and disassembly, and he asked the victim to help him disassemble the boom so that they could insert the 70-foot section. Note: The crane operator reported that he had some experience in his training with disassembly and assembly of booms, as it had been covered briefly in his crane operator classes. He had performed boom assembly and disassembly procedures with the company’s more experienced crew many times, but he had not taken the lead in disassembling a boom before the day of the incident.
The supervisor called a coworker who immediately called 911, and then company managers. Within about 5 minutes, a hydraulic crane located nearby was positioned next to the lattice boom. The crane operator rigged a strap to the lattice boom, connected it to the hook of the hydraulic crane, and lifted the boom off the victim (Photo 4). The two pins were driven back into place to secure the boom sections.
Approximately 5 minutes after receiving the 911 call, EMS personnel arrived and extricated the victim. They attempted resuscitation but were unsuccessful. At 8:45 a.m. cardiac monitoring indicated asystole (disruption of normal heart beat). EMS personnel notified the EMS medical director of the victim’s condition and resuscitation efforts were suspended. The victim was transported to the hospital at 9:15 a.m. where he was pronounced dead.
Cause of Death
The medical examiner’s office reported that the cause of death was traumatic asphyxiation due to blunt force trauma.
Recommendation #1: Employers should ensure that manufacturer’s safety recommendations for proper blocking and support procedures to prevent movement of the boom sections are implemented when disassembling cranes.
Discussion: According to the crane operator involved in the incident, the operator’s manual located in the truck-mounted crane was the sole source of safety procedures for crane operation at the company. The crane operator stated that he had observed the assembly and disassembly of the boom crane with the assistance of a second or “helper crane.” He stated that the “helper crane” would support the boom by hooking onto a nylon strap wrapped around the lower boom section. At other times, if the helper crane was not available, they (the crane operator and one of the team of two workers with more experience in disassembly) would use the live mast as a hoist and connect a hook from the live mast to a nylon strap wrapped around the lower boom section of the boom. Tension on the hoist cable would support the boom. Workers interviewed by NCOSHA reported that this was a common practice, that they believed these procedures were written in the operator’s manual, and that the company did not have any alternative written procedures. The trainer for crane operators employed by the company agreed that this was the practice, provided that the crane boom was 80 feet or shorter. An authorized manufacturer’s procedure required the retraction of the live mast to a 20-foot length, and attachment to the lower boom section with the lift links (Photo 5). As an alternative, the manufacturer’s disassembly procedure recommended blocking tightly under the pin connection before removing the pins.2 The crane operator involved in the incident indicated that this would be too time consuming for the task. The operator’s manual did not include instructions on the use of a “helper crane,” or instructions for connecting the live mast hoist to a strap wrapped around the boom, indicating that the workers were mistaken about the safety procedures written in the operator’s manual for this truck-mounted crane. The company safety manager indicated that the company’s written crane operation procedures were out of date and the company had made it a policy to use only the safety procedures written in the operator’s manual for each crane. Supervisors should ensure that safety measures specified in the manual are followed and the procedures are reviewed with all involved workers before each assembly and disassembly. Since the operator’s manual does not assign responsibility for crane assembly and disassembly tasks, company policy and retraining should also cover these responsibilities.
“Incorrect Disassembly Of A Pin Connected Boom May Result In Machine Damage, Personal Injury, Or Even Death. Before Disassembling Boom, Read And Be Sure You Understand Fig. 7-23 And The Disassembly Procedures In This Section Of The Operators Manual. As An Alternative Disassembly Procedure, Block Tightly Under The Pin Connection Before Removing Pins. Never Stand Under A Boom When Removing Pins.”2 Note: The above warning is provided as an example of the information contained in the operators manual for the crane used in this incident and is only a small part of the section on disassembly. For complete information regarding the manufacturer’s safety recommendations for crane handling and operation, employers and operators should always refer to the operator’s manual for that specific crane.
•Block boom sections under each section’s support member to ensure the weight of the section is safely supported.
•Do not block between the support members, as this may cause damage to the boom section.
•Always check to ensure boom pendants (boom suspension cables or lines) are properly located before removing a connecting pin. The boom pendant should be between the pin and the crane body so that it supports the boom section closest to the crane body.
•When removing pins, block or support the removing boom sections(s) to prevent their collapse.
The Alert also recommends that riggers and ground workers located near hoisting operations follow the correct assembly and disassembly procedures when setting up or dismantling a crane, check to make sure boom sections are blocked or supported before removing pins, and warns them not to stand under the boom.3
Recommendation #2: Employers should ensure that all workers assigned to disassemble or assist in disassembling cranes are trained on correct procedures, using a language and literacy level that workers can understand, so that they can recognize the hazards of improper disassembly sequences.
Discussion:The victim was not specifically trained in safety hazards associated with disassembling booms in English or Spanish, and had never helped disassemble a crane boom before. The crane operator spoke English and, although a trained and certified crane operator, had never performed boom disassembly procedures as the lead worker before. He reported that there was a sense of urgency to get the crane ready for the tasks at hand, and that he forgot about making sure that the boom was supported. Just before the incident occurred, he motioned to the victim to move as the boom could fall on him, but the victim moved from under the center section to under the lower boom section.
This incident underscores the importance of ensuring that all members of the crew have a basic understanding of the correct procedures involved in hazardous operations such as assembling or disassembling cranes. Additionally, if the victim had fully appreciated the potential for uncontrolled movement, he may have positioned himself to the side of the boom rather than underneath, minimizing the danger of being struck by falling boom sections. The training should reiterate that boom sections need to be supported during disassembly, that standing anywhere near a crane during disassembly is hazardous, and that pins used to hold boom sections together are always to be removed while standing outside the boom, never under it. Training should emphasize that workers must stand to the side and reach through the lattice to remove the pins.
Information useful for safety training for workers who work around or operate cranes can be found in the NIOSH ALERT entitled Preventing Worker Injuries and Deaths from Mobile Crane Tip-Over, Collapse and Uncontrolled Hoisted Loads3 available through the NIOSH web site at http://www.cdc.gov/niosh or by calling 1-800-356-4674. The Alert contains a tear-out sheet that summarizes safety precautions for operators of mobile cranes and for those who work on or around mobile cranes. Including the Alert in jobsite training materials and posting the tear-out sheet at the worksite may serve as an additional means of communicating safe work procedures to workers. Fatality case reports provide another valuable source for use in safety training programs and can be accessed by using the NIOSH Website www.cdc.gov/niosh/face. FACE report No. 97-03 describes another fatality that occurred during crane boom dismantling.6
Workers should be trained using a language and a literacy level they understand. OSHA developed the Compliance Assistance: Hispanic Employers and Workers web page to assist employers with a Spanish-speaking workforce in learning more about workplace rights and responsibilities, identifying Spanish-language outreach and training resources, and learning how to work cooperatively with OSHA. In addition, the web page provides a list of OSHA’s Hispanic/English-as-a-second-language coordinators, fact sheets, Quick Cards, public service announcements, success stories, dictionaries, electronic assistance tools, and other useful information to help protect Hispanic employees’ health and safety. These materials are available at https://www.osha.gov/dcsp/compliance_assistance/index_hispanic.html 7 or can be obtained by contacting an area OSHA office. Information provided can be used by employers who are developing or improving safety and training programs for their Spanish speaking employees.