The Occupational Safety and Health Administration (OSHA) is a federal agency responsible for assuring safe and healthful working conditions for America’s workers. To address the most dangerous hazards in the construction industry, OSHA established the “Focus Four,” sometimes called the “Fatal Four.” These four categories represent the most frequent causes of serious injury and death in the sector.
Defining the OSHA Focus Four
The selection of these four hazards is based on a rigorous statistical analysis of fatality data collected by OSHA. Historically, these four categories consistently account for approximately 60% of all construction worker deaths each year. This pattern of concentrated risk allows the agency to strategically prioritize its resources for maximum impact on worker safety.
This statistical understanding informs OSHA’s approach to enforcement, inspection priorities, and the structure of its official training programs. The agency uses this data to focus attention on specific subsections of the construction standards found in 29 CFR 1926. This prioritization ensures that training programs, such as the 10-hour and 30-hour courses, dedicate substantial time to recognizing and controlling these high-risk scenarios. The Focus Four designation directs industry attention toward the areas where intervention will save the most lives.
The First Hazard: Falls
Falls represent the largest cause of construction worker fatalities, leading to more deaths than the other three Focus Four hazards combined. This category encompasses elevation-related risks, including work on unprotected edges, improperly maintained scaffolding, and the misuse of portable ladders. OSHA mandates that employers provide fall protection for any worker operating at a height of six feet or more above a lower level.
This requirement drives the implementation of specific engineered safety systems. The three primary methods of protection are Guardrail Systems, Safety Net Systems, and Personal Fall Arrest Systems (PFAS). Guardrail Systems function as passive barriers and must meet specific height and strength requirements. Safety Net Systems are installed underneath the work area to catch a falling worker, and must be positioned close to the working level to minimize impact force.
PFAS involves an anchorage point, a full-body harness, and a connecting device, designed to stop a fall within a short distance and limit forces applied to the body. Proper training in the inspection and use of PFAS components, including calculating the total fall distance, is necessary for the system to function as intended. Ladder safety requires securing the ladder and ensuring the top extends at least three feet above the landing surface. Scaffolding must be erected and inspected by a competent person, with all platforms fully planked and equipped with guardrails.
The Second Hazard: Struck-By Objects
The struck-by hazard is defined as injuries or fatalities resulting from forceful contact between a worker and an object or piece of equipment. This hazard is divided into two main subcategories. The first involves falling objects, such as tools dropped from heights, unsecured materials, or debris from demolition activities.
The second subcategory involves swinging or moving equipment used on the ground, including large machinery like cranes, excavators, and heavy vehicles. Workers can be struck by the rotating superstructure of a crane, the bucket of an excavator, or materials being lifted. Poor visibility, congested work areas, and a lack of clear communication often contribute to these incidents.
Prevention for falling objects centers on containment and controlled access. Toeboards must be installed along the edges of elevated platforms to prevent materials from rolling off. Netting is often used beneath scaffolding to catch debris. Establishing controlled access zones beneath overhead work ensures that only essential personnel are permitted in the hazard area.
Mitigating risks associated with heavy equipment requires high levels of communication and visibility. Operators must be aware of all personnel working within the swing radius or travel path. The use of spotters or signal persons is a recognized method for safely guiding equipment movement. Workers on the ground must wear high-visibility clothing to ensure they are easily seen by the operator.
The Third Hazard: Electrocutions
Electrocutions in construction involve a worker becoming part of an electrical circuit, leading to severe burns, internal injuries, or cardiac arrest. Common causes include direct contact with exposed or live wires due to damaged insulation or improper wiring. The misuse of temporary extension cords and power tools lacking proper grounding also contributes to this hazard.
A frequent scenario involves workers operating tall equipment like cranes or scissor lifts making contact with overhead power lines. This contact transmits high voltage through the machine and the worker to the ground, resulting in electrocution. Maintaining a safe distance from all overhead power sources is a foundational safety practice.
Prevention measures rely on controlling the source of electrical energy. Lockout/Tagout (LOTO) procedures ensure that equipment is de-energized and cannot be accidentally turned on during maintenance. This involves physically locking the energy isolating device and placing a tag identifying the worker responsible.
Ground-Fault Circuit Interrupters (GFCIs) protect against electric shock by monitoring current flow. If the GFCI detects an imbalance, indicating current is leaking through a person, it quickly shuts off the electricity. All power tools and cords must be properly insulated, maintained, and correctly grounded.
The Fourth Hazard: Caught-In/Between
The caught-in/between hazard involves workers being crushed or trapped between two or more objects, or caught within the moving parts of machinery. This includes trench collapses, where workers are buried under tons of soil, and being pinned between heavy equipment and a fixed structure. Workers can also be drawn into the moving parts of rotating equipment, such as pulleys, gears, rollers, or chains, often resulting in severe crushing injuries or amputation.
Trench collapses, or cave-ins, pose the greatest risk within this category, as one cubic yard of soil can weigh as much as a small car. OSHA mandates that any trench four feet deep or greater must have a means of access and egress within 25 feet of the worker. Trenches five feet deep or greater must be protected from collapse using shoring, shielding (trench boxes), or sloping (cutting the walls back to a safe angle). Proper machine guarding is the primary prevention method for rotating equipment, requiring guards to be securely affixed to prevent contact with moving parts.
The Importance of Training and Safety Culture
Addressing the Focus Four hazards requires comprehensive workforce education. Formal training ensures all personnel understand the regulatory requirements and practical methods for hazard mitigation. OSHA offers Outreach Training Programs, specifically the 10-Hour course for entry-level workers and the 30-Hour course for supervisors and safety directors.
These programs dedicate substantial time to the Focus Four, emphasizing hazard recognition and prevention techniques. The 10-Hour course provides basic awareness, while the 30-Hour course delves into the standards and the responsibilities of a competent person. This tiered approach ensures that both management and labor have the necessary knowledge to identify unsafe conditions.
Cultivating a strong safety culture translates knowledge into daily practice. A strong culture is characterized by open communication where workers feel comfortable reporting hazards or stopping work without fear of retaliation. Regular safety meetings, often called toolbox talks, reinforce hazard communication and discuss site-related risks. When safety is viewed as a shared value, the principles learned in training are proactively applied across the job site.
OSHA Compliance and Enforcement
OSHA maintains its standards through a compliance and enforcement process, ensuring employers address the Focus Four hazards. The agency conducts inspections, which can be triggered by a worker complaint, a referral, or a programmed inspection targeting high-hazard industries like construction. Investigations following a serious injury or fatality are prioritized, dispatching compliance officers to the site to document conditions and determine the root cause.
When an inspection reveals a failure to comply, OSHA issues citations detailing the violation and proposing financial penalties. The severity of the penalty is determined by the nature of the violation, with categories including serious, repeat, and willful violations. A serious violation exists when the employer knew of a hazard that could cause death or serious physical harm.
A willful violation is issued when an employer intentionally disregards the law, resulting in the highest financial penalties. Enforcement actions motivate employers to implement and maintain effective safety programs targeting the Focus Four. Employers are also required to maintain accurate records of all work-related injuries and illnesses on the OSHA 300 logs, allowing the agency to track injury trends.