Construction Incidents Investigation Engineering Reports
This webpage includes forensic engineering investigation reports of catastrophic incidents conducted by the Occupational Safety and Health Administration (OSHA), Directorate of Construction – Office of Engineering Services. Many of these incidents resulted in one or more worker fatalities, and property loss, lawsuits, or settlements of millions of dollars. Each investigation was performed at the request of an OSHA field office or State Plan OSHA as part of an enforcement inspection. These reports may include professional opinions of the investigating engineer; incident root cause opinions; factual data; and findings.
These investigative reports were prepared to assist the OSHA field office or State Plan OSHA. The alleged violations of standards referenced in the reports are findings and recommendations of the investigating engineer to assist the requesting office. The violations and findings recommended in the report does not constitute an OSHA violation of a specific party named in the report. The OSHA field office or State Plan OSHA may issue the recommended violation; additional and/or different violations of standards to the appropriate party. The final resolution of the enforcement case may result in changes to the initial proposed alleged violation(s).
The intent of these reports is to help employers, workers, construction engineers, project managers, and regulatory bodies identify problems in construction design, project management, and management of field engineering changes. Hopefully, this information will help reduce future incidents, fatalities, and serious injuries.
The web-version of the report may not include all photographs, schematics, computations, tables, figures, and other non-text items. Otherwise, the text of each report is identical to the original report. The report is maintained as part of the OSHA enforcement case file in the appropriate Area Office or State Plan.
Wood roof trusses collapsed during installation and fell onto the ground floor where a Dollar General store was under construction. The roof framing consisted of 66 wood piggyback base trusses spanning 70 feet. Two employees were injured after falling approximately 12 feet and a third employee cutting lumber inside the building, was fatally crushed by the falling trusses.
The last span of the Herbert C. Bonner Bridge (Bonner Bridge) under demolition collapsed in Dare County, North Carolina. An employee engaged in the steel cutting, was killed. The collapsed span was the navigation span of the Bonner Bridge measuring 180 feet long, 24 feet wide, and approximately 60 feet above sea level.
Three employees were working on a scaffold attached on the fourth floor of a hotel, when the cables supporting the scaffold suddenly failed and the scaffold collapsed. The scaffold, approximately 17 feet long and 15 feet wide, was attached to the building and was being used to transfer materials into the building. At the time of the collapse, the employees were moving materials from the scaffold into the building. The employees and materials fell 10 feet to the concrete floor below resulting in three employees being injured.
A pedestrian bridge under construction collapsed and fell over the SW 8th Street near SW 109th Avenue in Miami, Florida. The bridge was being constructed to connect the FIU campus with the City of Sweetwater. The bridge, at this stage of construction, consisted of a single concrete truss spanning approximately 174 feet and weighed approximately 930 tons. The concrete bridge was cast at a nearby off-site location and then transported to its final location. At the time of the collapse, motorists were waiting underneath the bridge for the traffic light. One employee and five motorists were fatally injured, and another employee permanently disabled.
The project involved the reinforcement of the KOZK 1,891-foot-tall guyed communication tower just north of Fordland, Missouri. The tower required structural modifications to support the transmission line replacement. However, the suggested diagonal replacement procedure was flawed in that it compromised the effectiveness of the integrated surrounding braces and the load bearing capacity of the tower legs. At the time of the collapse, contractor was performing structural modifications to the tower.
Three hammerhead tower cranes collapsed within hours of each other; two in Miami and one in Ft. Lauderdale, Fla., during heavy winds in the wake of Hurricane Irma. The three cranes were the same model SK-315. There was another SK 315 model crane that did not collapse which was at a much lower height and was shielded by tall structures. There were Terex manufactured cranes other than SK 315 in the area which did not fail. The crane jibs detached from their turntables due to turbulent wind and the cranes failed.
To repair a damaged or misaligned buried drainage pipe, the employees were hand-digging a trench besides a newly installed concrete barrier, more than 130 feet long. The concrete barrier collapsed into the trench while the employees were digging the trench. Two employees in the trench were killed.
Three employees were engaged in installing a new antenna for a local TV station at the top of a 951-foot tall antenna tower constructed in 2009. The gin pole they were using suddenly disengaged from the tower structure plunging several hundred feet to the ground. The employees were tied to the gin pole and fell with it and were killed. The cause of the disengagement was the failure of attachment between the gin pole and the tower structure.
Two scaffolds, known as Doka Xclimb 60 loading platforms, collapsed and several pieces of debris from the platform fell to the ground from the 48th floor of a high-rise residential building under construction in downtown Miami. The contractor was hydraulically climbing two scaffolds together, from the 47th floor to 48th floor and both scaffolds failed.
A formwork table being installed for pouring concrete for construction of a multistory residential building failed and collapsed. The crews were installing the formwork tables on the 15th level. One of the employees fell to the ground along with the failed formwork table and was killed.
A Manitowoc MLC300 crawler crane engaged in driving piles with a vibratory hammer for the construction of the new Tappan Zee Bridge collapsed and fell over the existing Tappan Zee Bridge. The incident occurred on the Rockland County side. The 256 foot-long boom of the crane fell over the existing bridge (north and southbound lanes of Interstate I-87/I-287).
Miami-Dade College (MDC) decided to demolish the parking garage involved in 2012 incident and to build a new structure. During the construction of the replacement garage, two precast double tee beams collapsed on the fourth level of the new parking garage.
A Liebherr crawler crane, approximately 570 ft. high, collapsed in lower Manhattan, killing one motorist. The crane operator was attempting to lay down the crane in high wind when the crane suddenly collapsed and overturned. The crane had a luffing jib, 371 ft. long and a 194 ft. long boom. There was no load on either the boom or the jib hooks.
At Newark Liberty International Airport, aircraft hangar no. 14, undergoing demolition, unexpectedly collapsed. The building was largely used for storage and no airplanes were parked inside the hangar. The contractor made numerous cuts on columns contrary to the consultant’s instructions and these additional cuts compromised the stability of the structure.
A 12-story steel framed building with concrete floor slabs was under construction and the exterior of the building was to be clad with glass curtain walls. The construction was almost complete on March 23, 2015 when during the disassembly, one of the mast climbing work platforms collapsed. The mast supporting the platform partially collapsed. At the time of the incident, there were four employees on the platform perched near the 9th floor. All four fell to the ground with the falling mast and platform. Three were killed and the fourth fell on the roof of a portable toilet, and suffered severe injuries.
A construction incident occurred on Monday, January 19, 2015 near downtown Cincinnati at approximately 10:30 p.m. when the center and east spans of a ramp bridge being demolished suddenly fell 15-20 feet onto southbound interstate I-75 south freeway, killing a foreman and injuring the excavator operator. At the time of the incident, concrete slab was being removed from the deck of the ramp as a part of the demolition of the Hopple Street Ramp Bridge. The demolition work began a day earlier but had to be stopped due to concerns about some steel girders lifting off their bearings. Work resumed after the remedial measures recommended by the engineers were carried out. Those measures proved inadequate, and the incident occurred.
On November 13, 2014 at approximately 10:30 a.m., a pedestrian bridge under construction at the Wake Technical Community College at the Northern Wake Campus, Raleigh, North Carolina, suddenly collapsed killing a worker. Four employees were injured. At the time of the collapse, concrete was being poured on the metal deck to provide the walking surface. A few hours later, another similar bridge, also under construction, within a block of the first incident, collapsed at approximately 12:30 a.m. in the middle of the following night. No one was injured in the second incident. No construction activities were going on during the second incident. Both bridges were part of the expansion of the Northern Wake campus which was well underway.
A fatal incident occurred on December 30, 2014 at approximately 8:30 a.m. at the Ford Kansas City Assembly Plant (KCAP) in Claycomo, MO. The incident happened when the welds on a bracket holding a safety pin supporting the weight of a carriage suddenly failed, causing the carriage to slip off the pin and fall, pinning an employee who was working below the carriage.
During the "Hair Hang Act" at the Ringling Bros. and Barnum & Bailey Circus show in Providence, RI, eight performers were suspended from their hair with their bodies free to dance in a choreographed acrobatic manner. Suddenly, during the act, the metal apparatus supporting the performers plummeted to the floor. Two of the performers sustained critical injuries. In total, there were injuries to nine employees. This incident occurred because the carabiner used to support the performers failed due to being improperly loaded.
On March 25, 2014, two communication towers owned by Union Pacific Railroad (Railroad) collapsed in Blaine, KS, killing two workers. The project consisted of dismantling an older communication tower with all its appurtenances (e.g., antennas, dishes, coaxial cables, etc.). The older tower was located next to a recently constructed tower. At the time of the incident, a gin pole was being raised on the older tower to lower a 10 ft. diameter dish when the rigging of the gin pole suddenly failed causing the 60 ft. tall gin pole to plummet down, resulting in the collapse of both the towers. One employee was situated approximately 20 ft. below the top on the older 250 ft. high tower and was engaged in disconnecting the 10 ft. diameter dish and another employee was on the same tower approximately 80 ft. from the top. One worker died at the scene and the other was pronounced dead at the hospital. There were two additional employees at the site who were not injured.
On February 1, 2014, at approximately 11:37 a.m., a 340 ft.-high guyed telecommunication tower (cell tower), suddenly collapsed during upgrading/construction activities. Four employees were working on the tower removing its diagonals. In the process, no temporary supports were installed. As a result of the tower's collapse, two employees were killed and two others were badly injured. The cell tower fell onto the guy wires of an adjacent smaller cell tower and caused it to collapse, killing a firefighter while he was rescuing the injured employees on the ground. The collapse of the smaller tower is not covered in this investigation.
A massive collapse occurred at a plant producing nutritional supplements for animal feed. There were nine bins each 8 ft. x 8 ft. x 27 ft. high, framed over the roof of the building. During filling of one of the bins with lime stone, the supporting structure collapsed and the entire plant had to be shut down. The facility was originally constructed around 1972. Two employees were killed and thirteen others were injured.
On November 2, 2013, at approximately 1:30 p.m. an incident occurred at the construction site of the runway expansion project of Ft. Lauderdale-Hollywood International Airport when five precast concrete beams fell off their bearings, and an additional five beams slid off their bearings but remained over the concrete bents. The beams fell some 25 feet onto the railroad tracks owned by Florida East Coast Railways which operates trains multiple times a day hauling commodities across Florida. The beams were placed just a couple of days earlier and were to support the actual runway consisting of a post-tensioned concrete slab. One employee sustained minor injuries but the potential for multiple fatalities was very obvious.
On November 13, 2013 an incident occurred at the construction site of a parking garage in Ft. Lauderdale, FL, where two precast walls weighing about 34 tons each suddenly fell. The walls were erected less than an hour before they fell. Two employees sustained injuries although this incident could have resulted in multiple fatalities. The parking garage was being constructed as a part of a larger project to construct new rental apartment buildings. The entire complex was called RD Flagler Village.
A construction incident occurred on May 23, 2013, at approximately 1:45 p.m., when a prestressed concrete double tee partially collapsed while it was being jacked, killing one employee and injuring another. The double tee was 60 ft. long and 9 ft. wide, with a depth of 2 ft. 3 in. and a slab thickness of 4 inches. The weight of the double tee was approximately 42,800 pounds. The incident site was the Westlake Garage of the Westfield Montgomery Mall in Bethesda, MD.
On May 28, 2013, a construction incident occurred at the site of Verizon Wireless cell tower in Georgetown, MS. The 300 ft. high cell tower was being equipped with a gin pole to replace the old antennas with new ones. While the gin pole, approximately 40 ft. tall was being raised, the rigging of the gin pole block suddenly failed, killing two workers located on the tower.
An incident occurred on March 31, 2013 inside the turbine building of Unit 1 at the Arkansas Nuclear One power plant in London/Russellville, AR. During the scheduled refueling outage of Unit 1, it was pre-planned to replace the turbine stator. While the old turbine stator was being removed and transported to the trailer deck, the temporary overhead crane supporting the old stator suddenly failed and collapsed, killing an employee. Eight other employees were injured. The turbine stator weighed over a million pounds.
On April 18, 2013, partial collapse of a masonry wall occurred during construction of the Goodwill Retail Store in Hendersonville, TN. As a result of the wall collapse, two employees were killed and one was injured. The investigation and evaluation were based on the information provided by the Division of Occupational Safety and Health of the State of Tennessee. The project consisted of construction of a one-story Goodwill Retail Store, approximately 170 ft. wide x 180 ft. long.
A portion of the parking garage under construction suddenly collapsed, trapping and killing four employees and injuring three others. The six-story garage was 305 ft. x 390 ft., and 62 ft. high and was being constructed with precast concrete structural members. The collapse occurred over an area of 122 ft. by 132 ft. The heavy fallen concrete pieces weighed approximately 3,300 tons.
On September 6, 2012 at approximately 5:00 a.m., a partial collapse of the second level slab occurred during construction of the 159-room, ten-story building, Hyatt Place Hotel in Omaha, NE. At the time of the collapse, the northwest section of the second level was being placed with fresh concrete over the formwork. Twenty-five employees were working with the wet concrete. Six of them on the formwork fell 10 to 18 feet below to the ground level. Three employees were injured.
The building under construction consisted of five townhouses, each four stories high. The structure consisted of load-bearing masonry walls with cold-formed steel C-joists and metal deck at each floor. At the time of the incident, materials were being delivered to the 4th floor. The front 20 feet of the floor collapsed over the third floor pancaking the floors below. One worker killed, 1 injured.
The project consisted of demolition of a 1920 built two-story warehouse building as part of Columbia University's expansion. During demolition, the building partially collapsed in an unplanned manner. One employee was killed and two employees were injured. The building was being used as a warehouse and a commercial parking garage.
The front bay of the five-story building under construction suddenly collapsed. At the time of the incident, concrete was being pumped to the third floor. The building was a hybrid construction of load-bearing light metal framing with interior steel rolled shaped beams and columns, and masonry walls at the core. One worker killed, 2 injured.
A 500-ton Liebherr mobile crane collapsed amid thunderstorms and heavy rain while it was being lowered to the ground. The crane's telescopic boom was 152 ft. and the attached lattice jib was 276 ft. long. The crane had been delivering materials over the cathedral building after earthquake damage. The crane tipped, overturned and fell its full length. One worker injured.
A systems-engineered metal building (pre-engineered building) collapsed during construction, killing one worker and injuring another. The project consisted of erecting four buildings, with length varying from 35 ft. to 300 ft. and width varying from 20 ft. to 150 ft. The building unit was intended to be a new manufacturing plant.
The east wall of the 30 ft. high concrete equalization basin suddenly separated from the rest of the structure under the hydrostatic pressure, and fell over a one story control room structure killing two employees.
A partially erected precast concrete frame of the 3,300 car parking garage suddenly collapsed. The structural design was hybrid: precast concrete columns and beams, and cast-in-place post-tensioned floors. The collapsed frame was approximately 65' long, 56' wide and 80' high weighing approximately 900 tons. Two workers were injured.
A mast climbing platform partially collapsed at a 21-story concrete framed condominium building under construction. The mast and one half of the platform remained intact. Immediately before the incident, the platform descended from the 13th floor and stopped at the 11th floor when one half of the platform suddenly separated from the main frame (motorized unit) and fell to the seventh floor. Three workers were killed.
A spirally shaped pedestrian walkway steel bridge approximately 575' long and 11' to 18' wide under construction collapsed. At the time of the incident, concrete was being poured over the bridge deck. The collapse was massive, involving over seventy percent of the bridge. At the time of the collapse, the entire bridge structural frame was being supported over fifteen temporary shoring towers. One worker killed, 18 injured.
The crane was assembled at the site with a 420' boom, 240' mast, 61' spar and 836,000 pounds of main counterweight attached to the spar. An additional 836,000 pounds of auxiliary counterweight was to be attached to its pendants suspended from the mast tip at 105' from the axis of the crane. With this configuration, the crane would have a million pound lifting capacity at a maximum boom radius of 160'. The incident occurred during the installation of the auxiliary counterweight. Four workers were killed and 6 injured.
A 250 ft. high tower crane in uptown Manhattan, NY collapsed when the polyester slings supporting the suspended collar failed. The collar was positioned around the just "jumped" tower sections and was to be laterally tied to the building under construction to provide lateral support to the crane mast. There were six fatalities and injuries to one person.
The incident occurred during the construction of a five-story poured-in-place concrete parking garage. The structural design consisted of cast-in-place one way post-tensioned slabs and post-tensioned beams. The columns were also cast in place. At the time of the incident concrete was being poured on the 6th level. There were no re-shores below the third level. One worker was killed, and 21 injured.
The new bridge under construction on U.S. 90 to connect the towns of Bay St. Louis and Pass Christian was to replace a nearby old bridge destroyed by Katrina. The incident occurred when the steel forms of a bridge column suddenly collapsed and fell into the bay while the form was being filled with wet concrete. Nine workers fell with the column into the bay. Two workers were killed.
A new medical office building was under construction when the long span wood roof trusses collapsed. The workers erected the trusses a few hours before and were installing temporary and permanent bracings and purlins at the time of the incident. Shortly before the incident, three bundles of 2x6s to be used as purlins and braces were placed over the top chord of the center trusses. Two workers were seriously injured.
The project, 40,000 square foot retail and office complex with two levels of parking, was in the first phase of construction, i.e., excavation and site stabilization, when the incident occurred. A steep excavated slope, more than 40 foot high suddenly collapsed. The collapsed earth deposits buried a nearby excavator and killed the operator inside the cab.
The project consisted of demolishing a steel bridge 850 ft. long and 27 ft. wide with twelve spans of varying lengths. The steel girders' depths varied from 48" to 114" and the bridge deck consisted of a 9" thick concrete composite slab. During demolition, two spans collapsed in an unplanned manner, killing one worker and injuring another.
Two construction workers fell twenty stories to the ground and died when the stripping platform they were working on failed. The incident occurred during the construction of a 22-story condominium building. The platform was supported on structural framing resting on the 19th floor concrete slab and on the underside of the 20th floor slab. There were three other employees on the platform at the time of the failure, but they were able to hang onto the railing and the net, and were rescued.
The project consisted of construction of a large, one-story concrete and steel structure for an indoor swimming and diving pool with bleachers. The roof trusses were curved and spanned 190 feet and weighed approximately 80,000 pounds. The incident involved the collapse of three long span steel roof trusses and several steel bar joists that fell approximately 50 feet to the ground. Two workers were killed, 2 injured.
The project consisted of ten 3-story buildings to construct 82 townhouses. Tunnel forms were used by the construction team for casting concrete on the floors and in the walls. The incident occurred while concrete was being poured on the third floor of one building. A portion of the building collapsed killing two workers and injuring three others. The building was approximately 53 ft. wide and 150 ft. long.
A parking garage, part of the Tropicana Casino and Resort expansion project collapsed during construction. The ten-story parking garage was designed as a cast in place concrete structure with precast floor filigree system. At the time of the incident, concrete was being cast on the 8th level. The collapse resulted in the failure of five levels of an exterior bay. Four workers were killed and 20 injured.
The 1,000 ft. guyed tower was being modified to add a new HDTV antenna and additional equipment. Installation of horizontal braces and replacing the top 14 ft. with a new 6 ft. tower section were to be undertaken. The crew had positioned a track and a gin pole on one face of the tower as a means to hoist the new antenna. The load line was attached to a block on the tower some thirty feet above the base. As the load line was tensioned, the tower collapsed killing three employees.
Four employees were placing grout bags and other materials on the cantilever section of the scaffold at the Hathaway Bridge construction site in Panama City, FL. As the grout bags were placed on the cantilever section, the scaffold suddenly failed, causing the employees to fall into the water. One worker was killed, 3 injured.
The 1965-foot high -KDUH-TV antenna tower was under contract to replace certain tower diagonals and struts to support a new high-definition TV antenna and other equipment. The tower consisted of 63 sections, each 30-foot high. The crew was replacing existing diagonals with new diagonals when the tower collapsed. Three workers were killed.
Two 142 ft. high scaffold towers collapsed, killing five workers and injuring 10 others. The towers were erected to provide a working platform for the facade renovation of a 1914 era 20-story steel framed masonry building. The face bricks and steel window lintels had already been removed from the 6th to the 14th floors and the cement plastering work was being done. At the time of the incident, two workers were manually hoisting a cement bag to the top of the scaffold tower.
The project consisted of fabrication and erection of structural steel framing consisting of round steel pipes to support two billboard signs, on the two opposite faces, each weighing approximately 5,400 pounds. The workers engaged in electrical and bill board installation were finishing the newly erected sign. The billboard structural framing suddenly collapsed killing all three workers and crushing the cars parked below.
A tilt-up concrete wall 23' high and 20' wide, weighing 40,000 pounds, suddenly collapsed crushing three workers. The structure comprised of steel framing with steel columns, steel joist girders, joists and tilt-up wall panels on the perimeter.
The project consisted of construction of a six-story parking garage. The 55-foot long mast climbing platform consisted of 20 foot fixed platform plus extensions on either side supported in the center by a single mast. Three sections, each 5-foot long were installed on one side, and four sections were installed on the other side. The side, which had four sections collapsed. 3 workers were injured.
A 44 ft. tall reinforcing steel cage weighing 80 tons fell over and killed one of the two workers working near the top of the cage. The deceased worker was caught between the collapsing reinforcing cage and the concrete footing surface. At the time of the incident, the two workers were installing horizontal ties. The wind at the time of the incident was about 25 mph.
The 1889-foot high antenna tower consisting of 64 sections, each 30 feet high, was being rehabilitated by replacing selected horizontal and diagonal members and guy wires. The workers were 1480' above the base replacing existing diagonal members when the tower collapsed. Three workers were killed.
Construction was underway at the Portland International Airport in Portland, Oregon to add four additional levels of parking to transform the existing two-story precast concrete parking garage into a seven level parking structure. Two partially completed bays of structural steel, most of which were erected the same day, collapsed killing three ironworkers.
A 1462 feet high antenna tower, collapsed while "jumping" a gin pole with a track near the top of the tower to replace an existing antenna. The workers fell to the ground with the falling sections of the tower. Three workers were killed.
A steel structure under construction 176 ft. x 312 ft. and 130 ft. high collapsed at the construction site for the Olympic Aquatic Center in Atlanta, Georgia. The structure, was an addition to the existing pool structure. Just prior to the collapse, the steel erection crew had erected a steel frame and a pair of steel joists spanning 176 ft. from an existing structure to the erected steel frame. The failure occurred within 15 to 30 minutes after the crane was released from the paired joists. The incident did not result in any injuries.
The building project under construction was a 31-story condominium complex. Five employees were applying stucco to the fascia walls when the platform of a mast climbing work platform (scaffold) collapsed. Three employees were on a modified cantilever deck section, which was connected to platform extensions attached to the main platform. The cantilever deck failed and as a result, the three employees fell about 75 feet where they were fatally injured. The other two employees working on the platform, were able to grab and hold on to the structure, and sustained only minor injuries.
A 350 ft. high guyed radio transmission tower collapsed during the final phase of its construction. Three FM antennas were already hoisted and fastened to the top sections of the tower. On the day of the incident, two workers positioned near the top section of the tower were beginning to lower the gin pole from the top section of the tower to the ground. The gin pole suddenly dropped and struck the coaxial cable, followed by the collapse of the tower. Both workers, who were tied to the collapsing tower, fell to the ground, resulted in the death of one worker and serious injuries to the other. The tower structure consisted of 25 pre-fabricated steel sections, each 10 ft. or 20 ft. in height.
A pile top drill unit and a 206 feet long pipe casing, 68-inch diameter suddenly dropped 25 feet into the soft ocean sediment bed as the crane of the jack-up barge was releasing a 80 ton bottom hole assembly onto the platform of the drill unit. The fall of the drill unit caused injuries to three employees working on the platform. One of them was fatal. The steel casing was horizontally held above sea level by the jack-up barge, which was supported on four legs, each 7.5 feet square in cross-section.
A construction worker was killed and two workers were injured when their work platform, about 230 ft. above ground, was struck by a collapsing steel post, during the erection of the roof cable structure at the Georgia Dome in Atlanta, GA. The workers were in the process of hoisting the center truss in position to make the final connection of a diagonal cable to the bottom joint of the center truss. The construction workers were using hydraulic pumps to apply loads to the temporary jacking strands in order to make the permanent diagonal cable connection to the center truss.
The structural steel support system of an open excavation, 150 ft. x 208 ft. by 47 ft. deep collapsed causing a cave-in of several thousand cubic yards of soil. The excavation was done for the construction of a 12-story office building with four levels of underground parking. The collapse caused the internal support system to slide and fall into the open excavation. At the time of the incident, construction had stopped for the day and therefore did not cause any death or injury, though it had significant potential for casualties.
The building under construction, the Airside Building, consisted of precast concrete beams, columns and precast prestressed hollow core concrete planks. During the erection and placement of hollow core precast planks at the roof level, several precast concrete beams, column, and hollow core planks at the roof and concourse levels collapsed. One construction worker, on the concourse level, died due to the falling debris of the collapsed beams and planks. Another construction worker was seriously injured.
A tower crane collapsed in the center of the financial district in San Francisco, California. Four construction workers engaged in the climbing operation of the crane and one person on the street below the crane were killed. The SN 355 model crane, a climbing, luffing boom tower crane had a maximum reach of 192 feet and a maximum lift capacity of 17,000 pounds with two wire ropes. The height of the crane on the day of collapse was 298 feet and consisted of 15 identical sections added at different stages. On the day of the incident, climbing process was underway to add another tower section.
Only selected reports are posted on this webpage. For assistance with any of the reports, figures or illustrations, please contact the Directorate of Construction at (202) 693-2020.
- OSHA finds that structural engineers must specify the order and manner of replacing existing diagonals and strut members of cellular towers. Onsite judgement by workers engaged in retrofit of towers has often proven to be disastrous. (October 2018)
- OSHA finds that the contractors and engineers should consider turbulent winds causing uplift and vortex in areas exposed to tropical storms and hurricane. OSHA recommends analysis based on Computational Fluid Dynamics (CFD) calculations. (September 2018)
- OSHA finds that the contractor not laying the boom and jib in the face of impending wind in accord with the crane manufacturer's instruction caused the collapse of the crane. (July 2016)
- OSHA finds that contractors must exhibit abundance of caution and supervision during dismantling of mast climbing platforms, not to overload the platforms causing failure of the mast. (August 2015)
- U.S. Department of Labor Announces Initiative to Increase Awareness Of Trenching and Excavation Hazards and Solutions, OSHA News Release (November 28, 2018)
- U.S. Department of Labor Cites Five Contractors for Safety Violations Following Florida Pedestrian Bridge Collapse, OSHA News Release (September 18, 2018)
- U.S. Department of Labor Cites Pennsylvania Crane Manufacturer for Exposing Employees to Safety Hazards after Fatal Crane Collapse, DOL News Release (August 6, 2018)
- U.S. Department of Labor Cites Communication Tower Contractor Following Three Fatalities at Miami Work Site, OSHA News Release (March 27, 2018)
- OSHA finds that overloading led to Providence, Rhode Island, circus fall Ringling Bros. and Barnum & Bailey Circus cited for serious safety violation. OSHA Regional News Release, (November 4, 2014).
- US Labor Department and Federal Communications Commission announce working group to prevent fatalities in telecommunications industry. OSHA News Release, (October 14, 2014).
- Structural Collapses During Construction - Lessons Learned, (1990-2008) (PDF). STRUCTURE magazine. OSHA investigated 96 structural collapses during construction involving fatalities and injuries from 1990 to 2008. Construction errors contributed to 80% of the structural collapses while the remaining 20% of the incidents are attributed to structural design flaws. (December 2010).