The call comes at 2 a.m.: electrical contact, two workers hospitalized, Occupational Safety and Health Administration (OSHA) investigation imminent. By morning, insurers demand answers about liability exposure, regulatory violations, and prevention failures. The incident investigation reveals no utility location survey had been conducted prior to equipment operation, a single preventable failure that resulted in over six figures in workers’ compensation claims, third-party litigation, and OSHA penalties.
This pattern repeats across hundreds of construction sites annually. For claims professionals and risk managers, understanding the regulatory framework behind these incidents can inform both prevention programs and liability analysis during claim resolution.
According to the Bureau of Labor Statistics (BLS), construction recorded 1,075 severe occupational injuries in 2023, the highest annual count for the sector since 2011. The longer-term trend reflects ongoing challenges: incident rates increased steadily from 2011 through 2022 even as other industries improved, underscoring the need for more rigorous hazard identification and prevention strategies.
Understanding construction’s most serious hazards
Four hazard categories account for the majority of severe construction site incidents annually: falls, struck-by events, electrocutions, and caught-in/between accidents. OSHA designates these as the “Focus Four,” and they consistently represent a significant share of serious injuries and workplace safety violations across the industry. From a forensic perspective, these incidents share common characteristics: they tend to be preventable, typically involve multiple regulatory violations, and generate substantial liability exposure. However, other causes of construction incidents occur with similar frequency and warrant equal attention.
1. Falls from heights
Falls accounted for 38.5% of all construction fatalities in 2023, positioning fall protection compliance among the highest-priority prevention investments for any construction safety program. Construction accounted for 47.8% of all lethal falls across U.S. industries despite its small workforce share. For claims professionals, fall incidents typically generate the largest indemnity exposure and most complex liability questions of any construction hazard category. When evaluating fall claims, investigators should prioritize PFAS anchorage documentation and training records, as these two elements most frequently determine liability allocation.
The 6-foot rule
29 Code of Federal Regulations (CFR) 1926.501 requires fall protection when working at heights of six feet or greater. OSHA’s fall protection regulations establish specific equipment and training requirements that create clear compliance benchmarks. The following standards provide the framework for evaluating fall protection programs:
- Guardrail systems must maintain a top rail height of 42 inches (±3 inches)
- Systems must withstand 200-pound test loads without deflecting below 39 inches
- Personal fall arrest systems (PFAS) must provide anchorage capacity of 5,000 pounds per attached employee
These specifications translate directly into pass/fail compliance determinations, making fall protection violations among the most straightforward to document during post-incident analysis.
Training requirements
29 CFR 1926.503 mandates written training certification including employee name, training date, and trainer signature, with retraining required when workplace changes render previous training obsolete. Documentation gaps in training records frequently emerge as key liability factors during post-incident investigations.
2. Struck-by incidents
Struck-by incidents present unique investigation challenges because they often involve equipment operator decisions, signal communication failures, and environmental factors occurring simultaneously. Unlike falls, where a single protection failure may cause the incident, struck-by events typically result from cascading breakdowns across multiple safety systems. These incidents include flying objects, falling materials, swinging loads, and rolling equipment. OSHA designates struck-by incidents as one of the Focus Four hazards requiring heightened enforcement attention.
Crane signal person requirements
29 CFR 1926.1428 establishes mandatory dual testing for crane signal persons, creating an objective compliance standard that forensic investigators can verify through documentation review. Regulatory requirements include:
- Signal persons must pass both oral/written and practical examinations
- Violations result in penalties ranging from $150,000 to $287,150
- “Competent Person” supervision is mandatory during crane operations
Signal person certification records and competent person designation documents represent the first evidence requests in most crane-related incident investigations.
Documented case example
During tower crane disassembly at a multi-story site, the crane collapsed, resulting in a fatal injury to the operator. OSHA found no competent person directing operations (required by 29 CFR 1926.1404), disassembly did not follow manufacturer specifications, wind speeds exceeded safe limits, and no pre-disassembly planning meeting occurred. Willful violations resulted in $280,000+ in penalties. A competent person could have identified unsafe wind conditions and halted operations before collapse, potentially preventing the cascade of failures that led to the incident.
Wind speed protocols
29 CFR 1926.1431 requires assessment by a qualified person when wind speeds (sustained or gusts) exceed 20 mph at the personnel platform. Industry practice typically includes crane shutdown when wind speeds exceed 30 mph. Wind speed documentation and qualified-person assessments serve as primary evidence in post-incident investigations.
Vehicle operations
OSHA regulations establish specific inspection and safety device requirements for construction vehicles that create documented compliance trails. Fundamental requirements include:
- All construction vehicles must be equipped with adequate warning devices at the operator’s station
- Daily safety inspections at the beginning of each shift must document service brakes, parking systems, tires, horns, steering mechanisms, seat belts, and coupling devices per 29 CFR 1926.601
Missing or incomplete inspection records frequently serve as evidence of safety program deficiencies during post-incident investigations.
3. Electrocutions
Electrocution incidents generate complex liability questions involving multiple parties: equipment operators, utility companies, general contractors, and electrical subcontractors may all share responsibility depending on the circumstances. For risk managers, the multi-party nature of electrical incidents makes early evidence preservation and party identification particularly important. In 2023, 142 workers died from exposure to electricity or arc flash, with construction and utility industries maintaining the highest electrical injury rates. OSHA designates electrocution as one of the Focus Four construction hazards.
The 10-foot clearance rule
Equipment operations near power lines require specific safety measures that create objective, measurable compliance standards. Primary regulatory requirements include:
- Maintain minimum 10-foot approach distance for lines ≤50 kV under 29 CFR 1926.1408
- When equipment traveling with no load will approach within 20 feet of power lines, 29 CFR 1926.1411 mandates a dedicated spotter with continuous contact with the driver/operator
The objective nature of distance requirements allows forensic engineers to calculate exact clearances using equipment position data and power line surveys, providing definitive compliance determinations.
Ground-fault circuit interrupter requirements
Employers must implement either ground-fault circuit interrupter (GFCI) or assured equipment grounding conductor programs per 29 CFR 1926.404(b)(1). GFCI protection applies to all 120-volt, single-phase, 15- and 20-ampere receptacles not part of permanent building wiring. Proper GFCI implementation and testing documentation can demonstrate regulatory compliance during post-incident reviews.
Electrical work zone boundaries
The National Fire Protection Association (NFPA) 70E standard establishes approach boundaries for electrical work. The Limited Approach Boundary for alternating current systems 50V-300V establishes 3.0 meters (10 feet) for exposed movable conductors. Only qualified persons with appropriate training should perform electrical work, with primary prevention strategy focusing on de-energizing circuits before work whenever possible. These NFPA 70E boundaries provide the technical framework for evaluating electrical work zone violations.
4. Caught-in/between hazards
Caught-in/between incidents occur less frequently than falls or struck-by events but carry disproportionately high fatality rates, making prevention investments in this category particularly cost-effective from a risk management perspective. Common scenarios include trench collapses, workers caught in unguarded machinery, being pinned between vehicles and fixed objects, or entrapment in cave-ins. Despite decades of regulatory focus on excavation safety and machine guarding, these incidents continue to cause preventable fatalities on construction sites.
The 5-foot trigger
Trenches 5 feet deep or greater require protective systems under 29 CFR 1926.652 unless excavated entirely in stable rock. OSHA’s excavation standards establish a detailed framework for trench safety that assigns specific responsibilities to designated personnel. Protective system and oversight standards include:
- Protective systems include sloping, benching, or shield systems designed according to specific soil classifications
- Daily inspections before worker entry and throughout each shift are mandatory
- A competent person must possess authority for immediate worker removal where evidence of possible cave-in, protective system failure, or hazardous atmospheres exists
- Competent persons bear responsibility for classifying soil and rock deposits as stable rock or Type A, B, or C soil
Trench collapse investigations almost always center on two questions: was a competent person designated, and was soil classification performed? Absence of either creates strong regulatory exposure.
Case example and machine guarding
An 8-foot trench collapsed without protective systems. OSHA investigation revealed no competent person had been designated and no soil classification had been performed. The resulting citation included penalties exceeding six figures for willful violations.
Beyond excavation hazards, 29 CFR 1926.300 requires guards on moving parts where employees may come into contact with them. Machine guarding violations frequently appear alongside other caught-in/between hazards, as unguarded equipment creates pinch points and entanglement risks throughout construction operations. Forensic analysis of caught-in incidents typically examines both the immediate mechanical failure and the broader guarding compliance program.
5. Scaffolding and ladder violations
Scaffolding violations consistently rank among OSHA’s Top 10 Most Frequently Cited Standards, with thousands of violations documented annually. This prevalence indicates widespread compliance gaps that create both prevention opportunities and significant liability exposure across the industry. According to BLS data, falls from elevated surfaces have historically accounted for approximately 80% of fatal slip, trip, and fall incidents and roughly 20% of nonfatal ones across all industries.
Forensic investigations of scaffolding incidents frequently trace failures back to gaps in basic compliance measures, including improper erection, inadequate inspection, and missing competent person oversight.
Competent person on-site requirement
29 CFR 1926.451 mandates that a competent person must be at the site directing and supervising during all scaffold erecting, dismantling, alteration, and moving. The regulation distinguishes between two roles with different qualification requirements. Applicable standards include:
- Scaffolds and components must be inspected for visible defects by a competent person before each work shift
- Scaffolds must be designed by a qualified person (with engineering credentials or equivalent structural design knowledge)
- Construction must follow that design, distinguishing “qualified person” responsibilities (structural design per 29 CFR 1926.451(a)(6)) from “competent person” duties (daily operational oversight, inspection, and maintenance per 29 CFR 1926.451(f) and (g))
This distinction between qualified and competent person responsibilities creates specific accountability that forensic analysis can trace when scaffolding failures occur.
Ladder angle requirements
Non-self-supporting ladders must be used at an angle where horizontal distance from top support to foot is approximately one-quarter of working length per 29 CFR 1926.1053(b)(5)(i), mathematically translating to 75½ degrees from horizontal, with side rails extending 42 inches above the top of access level or landing platform. Improper ladder angle and extension violations frequently contribute to ladder-related fall claims, and angle measurements from incident scene photographs can establish compliance status.
6. Equipment and machinery failures
Equipment failures often involve multiple contributing factors: maintenance deficiencies, operator error, and manufacturing defects may all play a role, requiring multidisciplinary forensic engineering analysis to establish causation. For claims professionals, equipment failure cases frequently require coordination between mechanical engineers, human factors specialists, and maintenance record analysts. These failures resulted in 265 severe injuries and amputations in the construction sector under federal OSHA jurisdiction in 2022 and 2023 combined.
Daily inspection and maintenance requirements
29 CFR 1926.601 establishes mandatory beginning-of-shift inspections that create documented compliance records. Required inspection elements include:
- Service brakes, parking systems, emergency stopping systems
- Tires, horns, steering mechanisms, coupling devices
- Seat belts, operating controls, and safety devices
Consistent inspection documentation demonstrates safety program implementation, while gaps in records often indicate broader organizational safety culture deficiencies.
All industrial trucks must meet applicable requirements for design, construction, stability, inspection, testing, maintenance, and operation per American National Standards Institute (ANSI) B56.1-1969 (29 CFR 1926.602). These ANSI standards establish baseline equipment specifications that forensic engineers reference when evaluating equipment condition and maintenance history.
7. Hazardous energy and lockout/tagout failures
Control of Hazardous Energy (Lockout/Tagout), which involves procedures that isolate equipment from energy sources and prevent accidental startup during maintenance, ranks #3 among most frequently cited OSHA standards across all industries. This ranking reflects both the hazard’s severity and the complexity of maintaining compliant programs across diverse equipment types. For organizations managing multiple facilities, lockout/tagout program consistency represents a significant audit priority.
Dual regulatory framework
Construction electrical work falls under both 29 CFR 1926.417 (construction-specific) and 29 CFR 1910.147 (general industry lockout/tagout). This overlapping regulatory structure creates compliance complexity that organizations must navigate carefully. Governing standards include:
- Section 1926.417 requires tagging of controls that are deactivated during work on energized or de-energized equipment or circuits
- The general lockout/tagout standard (29 CFR 1910.147) establishes procedural requirements including de-energization, lockout device application, and zero-energy verification
Understanding which standard applies in specific circumstances can inform both compliance planning and post-incident liability analysis.
Device and procedural requirements
Lockout and tagout devices must be capable of withstanding the environment to which they are exposed for the maximum period of time that exposure is expected, a requirement particularly relevant for outdoor construction environments with weather exposure, as specified in 29 CFR 1910.147. Beyond device durability, the regulation requires documented energy control procedures, authorized employee training, and periodic inspections of the lockout/tagout program. Forensic analysis of hazardous energy incidents typically examines both the physical lockout devices and the written program documentation.
8. Slips, trips, and same-level falls
Same-level falls represent the most common construction incident type by frequency, even though they typically generate lower severity claims than falls from height. For risk managers balancing prevention investments, the high frequency of these incidents means cumulative costs can rival those of less common but more severe hazard categories. Construction experiences 31.5 incidents per 10,000 full-time equivalent (FTE) workers for falls, slips, and trips requiring at least one day away from work, approximately three times the rate of general private industry.
Mandatory debris removal
29 CFR 1926.25 requires that form and scrap lumber with protruding nails and all other debris “shall be kept cleared” from work areas, passageways, and stairs. The regulation establishes ongoing housekeeping obligations that apply throughout construction operations. Housekeeping requirements include:
- Combustible scrap and debris “shall be removed at regular intervals” during construction
- Containers for garbage and hazardous wastes “shall be equipped with covers”
- Waste “shall be disposed of at frequent and regular intervals”
Site photographs taken before and after incidents provide the most direct evidence of housekeeping compliance, making immediate post-incident documentation particularly valuable for liability determination.
9. Weather and environmental conditions
Environmental factors like heat, wind, and lightning are frequently cited contributors to construction incidents, yet they represent some of the most defensible hazards from a liability perspective because OSHA has established objective, measurable thresholds that trigger mandatory protective measures. Weather data from the National Weather Service and on-site monitoring equipment can establish whether conditions exceeded regulatory thresholds at the time of an incident. OSHA has established specific thresholds, making weather-related incidents particularly susceptible to regulatory violations and heightened liability exposure.
Heat illness prevention
OSHA’s Heat National Emphasis Program establishes specific temperature thresholds and response protocols that create objective compliance standards. Heat illness prevention requirements include:
- 80°F heat index serves as the trigger for heat priority days and enhanced enforcement
- Workers should drink at least one cup of water (8 ounces) every 20 minutes while working in heat
- Employers must provide appropriate breaks and shaded rest areas
The 80°F heat index threshold provides the standard for evaluating heat illness claims, with failure to implement protective measures above this threshold creating clear regulatory exposure.
Wind speed limits
When wind speeds exceed 20 mph (sustained or gusts) at personnel platforms during crane operations, 29 CFR 1926.1431 requires qualified-person determination whether operations should continue. The 20 mph threshold applies to both sustained winds and gusts, establishing objective standards for evaluating crane operation decisions. Failure to cease operations or conduct qualified-person assessment can create per se violations.
Lightning and severe weather protocols
Workers must remain in shelter for at least 30 minutes after hearing the last sound of thunder, enforced under General Duty Clause Section 5(a)(1) with reference to NFPA 780 standards. Beyond lightning, severe weather protocols should address high winds, extreme cold, and other environmental conditions that affect worker safety. Weather monitoring documentation and shelter availability become relevant evidence when environmental conditions contribute to construction incidents.
10. Human factors
Human factors, including worker fatigue, inadequate training, language barriers, and communication breakdowns, require different forensic analysis approaches than equipment or environmental failures. While other hazard categories focus on physical conditions and regulatory compliance, human factors analysis examines organizational systems, management decisions, and workforce characteristics that shape worker behavior.
Research on extended work shifts demonstrates the magnitude of fatigue-related risk. Workers on shifts exceeding eight hours experience 15.0% injury rates compared to 10.4% for seven- to eight-hour shifts, representing 57% higher odds of injury. The relationship intensifies with duration: incident rates increase three-fold after 16 hours of work. Approximately 13% of workplace injuries relate to fatigue, close to one in eight incidents. For claims professionals, work schedule documentation and overtime records can establish whether fatigue contributed to incident causation.
Training, communication, and fatigue management
29 CFR 1926.21 requires appropriate training and instruction for all employees. Training documentation gaps and language accessibility failures frequently emerge as contributing factors during incident investigations.
Effective safety programs address training in languages workers understand, provide visual safety communications for multilingual workforces, and implement fatigue management policies for extended shifts. Forensic analysis of human factors incidents examines training records, communication protocols, work schedules, and organizational safety culture to identify systemic contributing factors beyond individual worker actions.
| OSHA construction safety checklistPrint and post this checklist on the job trailer for daily reference.Focus Four ControlsFalls: Guardrails at 42 inches, PFAS with 5,000-pound anchorage capacityStruck-By: Signal person dual testing, daily vehicle inspection recordsElectrocutions: 10-foot power line clearance, mandatory GFCI or assured grounding programCaught-In/Between: 5-foot trench trigger, documented competent person soil classificationHigh-Risk ControlsCompetent person on-site during scaffold erection with daily inspection logsHeat stress monitoring when heat index ≥80°F with water/rest/shade protocols30-minute post-thunder waiting period before resuming outdoor work |
How Rimkus supports construction safety programs
When construction incidents occur, technical investigation can help determine liability, coverage, and claim resolution strategy. Specialized forensic engineering capabilities, including 3D laser scanning for scene documentation, crane and rigging engineering analysis, power line proximity calculations, geotechnical soil classification reviews, and materials testing laboratories, could provide the technical foundation for claim resolution. Contact Rimkus today for an evaluation.
Frequently asked questions
What are the OSHA Focus Four hazards in construction?
The Focus Four hazards are falls, struck-by incidents, electrocutions, and caught-in/between accidents. OSHA designates these four categories for heightened enforcement attention because they account for the majority of severe construction injuries and fatalities. Falls alone represent 38.5% of construction fatalities, while the Focus Four combined represent an even larger share of serious incidents.
How long do employers have to report construction accidents to OSHA?
Employers must report work-related fatalities within eight hours and work-related inpatient hospitalizations, amputations, or losses of an eye within 24 hours. These reporting deadlines apply to all industries, including construction. Failure to report within required timeframes can result in additional citations and penalties beyond those related to the underlying incident.
What documentation should be preserved after a construction accident?
Critical documentation includes daily inspection logs, training records, competent person designations, equipment maintenance records, weather data, work schedules, and site photographs. For crane incidents, signal person certifications and qualified-person assessments are particularly important. Preserving electronic data from equipment, such as Event Data Recorder (EDR) information from vehicles, can provide objective evidence of conditions at the time of the incident. Early evidence preservation through a qualified forensic investigation team can protect documentation that may otherwise be lost or altered.
For slips, trips, and falls, which represent a significant share of construction site incidents, Rimkus deploys certified XL Tribometrists for floor slip resistance testing, human factors experts and biomechanists to analyze worker behavior and site conditions, and industrial hygienists to assess environmental hazards. This multidisciplinary premises liability practice addresses both the physical evidence and organizational safety culture behind these claims.
With more than 40 years of forensic experience and a network of 900+ experts across 100+ offices, Rimkus can help with construction safety investigations. Contact Rimkus today for a consultation.
This article aims to offer insights into the prevailing industry practices. Nonetheless, it should not be construed as legal or professional advice in any form.