The Evolution of Safety Management at Construction Sites: Introducing the Latest Countermeasures in the Civil Engineering and Construction Industry Aiming for Zero Occupational Accidents

Introduction

Construction sites are always adjacent to the risk of occupational accidents. With high-altitude work and operation of heavy machinery, construction sites contain a variety of hazards, making rigorous safety management the highest priority. In fact, the number of fatal accidents in the construction industry reaches about 300 people per year, making it conspicuous among all industries. Among these, falling from heights and contact accidents with heavy equipment rank high as causes of fatal accidents, and strengthening measures in these areas is indispensable to aim for zero occupational accidents (zero accidents).

Traditionally, site safety management has relied heavily on human observation and experience—morning briefings, safety patrols, and safety education for workers—so oversights and human errors were inevitable. However, in recent years, the “visualization” of safety management using rapidly evolving digital technologies and AI is progressing. This article focuses on the evolution of safety management at construction sites, and especially on the two areas of “fall prevention” and “prevention of contact with heavy equipment”, explaining in detail the current challenges and causes of accidents, the latest technical countermeasures, implementation examples and their effects, and the institutional background. We hope this will help you grasp the latest trends in safety management and consider efforts on priority issues toward zero occupational accidents.

Current Status and Challenges of Fall Accidents

The most frequent cause of fatal accidents in construction is falls from heights. Falls from scaffolding, falls through openings, and falls from roofs and beams—accidents associated with high-altitude work—are incessant. According to statistics from the Ministry of Health, Labour and Welfare, about 40% of fatal accidents in the construction industry are due to falls. The following challenges have been pointed out behind such fall accidents.

• Insufficient safety measures: There are cases where work continues with inadequate fall-prevention equipment, such as temporary scaffold handrails not installed, defective work platforms, or safety nets not installed. Some sites also lack sufficient fall-prevention fences at the edges of roofs or openings.

• Non-use or improper use of safety belts (fall-arresting devices): Some workers do not properly wear traditional waist-belt-type safety belts or work without any lifeline, which can lead to fatal fall accidents. In high-altitude work, wearing a safety belt and reliably hooking onto a lifeline is fundamentally mandatory, but negligence on site or overconfidence like “I’ll be fine” can mean these protections are not observed.

• Procedure and awareness issues: Human errors are frequent, such as stepping backward off the edge of scaffolding during demolition, or losing balance while moving awkwardly on scaffolding. Lack of adherence to procedures, insufficient experience, and lapses in attention are significant human-factor challenges.

As for current measures and regulations, in Japan the 2019 amendment to the Industrial Safety and Health Act made it mandatory to use “fall-arresting devices” (commonly called safety belts) when work at heights of 2 m (6.6 ft) or more lacks a secure work platform or handrail. In particular, wearing a full-harness-type safety belt became the basic requirement, and from January 2022 the use of the older waist-belt-type safety belts has been completely banned. Following this legal revision, the introduction of full harnesses has been spreading from major general contractors to small and medium construction sites, and some effects have begun to appear—for example, in 2019 the number of fatal fall accidents in construction decreased by about 26 people compared to the previous year. However, there have been reports that even when safety belts are worn, they are used improperly or the anchorage height is insufficient causing workers to reach the ground; thus, not only equipment performance but a change in awareness to “use correctly” remains important.

Thus, while measures in terms of equipment and rules are advancing for fall prevention, raising awareness on site and preventing human error remain challenges. Consequently, in recent years fall-prevention measures using the latest technologies have begun to be introduced at many sites, actively supplementing human oversights.

Latest Technologies and Countermeasure Examples for Fall Prevention

To reduce fall accidents, various new safety measures using technology have emerged at civil engineering and construction sites. Here are examples of the latest technologies effective in preventing falls from heights.

• AI surveillance cameras checking protective gear use and monitoring hazardous areas: Systems have appeared that place cameras on site and have AI analyze footage in real time to automatically check whether workers are properly wearing helmets and safety belts. For example, if AI detects a person on a steel frame not wearing a safety belt, it can instantly send a notification to a manager’s smartphone to prompt on-site warnings. Cameras can also capture human movements and sound an alarm when a worker is about to enter a restricted area. By having AI monitor high-altitude work 24/7 instead of relying on human watchers, oversights due to human error can be complemented and accidents prevented. In practice, major contractor Shimizu Corporation has applied its AI-equipped camera system “Kawasemi” not only to heavy equipment but also to high-altitude work monitoring, and is working on notifying with alarms when people are detected entering hazardous areas. The introduction of such AI surveillance technology is expected to greatly reduce “close-call” situations (hiyari-hatto).

• Wearable sensors for monitoring workers: Small wearable devices for workers are also becoming widespread to monitor safety conditions. Using wristwatch-type or helmet-mounted sensors, these solutions acquire workers’ location information and movement in real time and will immediately alert when detecting impacts from falls or drops. For example, if a worker falls from a height or loses balance on scaffolding, the sensor catches the abnormal acceleration and alerts nearby workers and supervisors with buzzers or notifications. This enables rapid rescue operations, helping to prevent secondary accidents and minimize damage. Some wearables also detect heatstroke risk from heart rate, body temperature, and humidity, helping prevent dizziness or falls due to poor physical condition. Furthermore, aggregated position data from these sensors can be used to remotely understand “which worker is where” and “is anyone approaching a hazardous area,” enabling applications such as area intrusion detection systems that automatically warn when someone enters a high-altitude work area.

• Immersive safety training using VR (virtual reality): Fundamentally reducing fall disasters requires improving each worker’s safety awareness. An effective method is immersive safety training using VR technology. Workers wearing VR goggles stand in virtual high places on a construction site and realistically experience scenarios such as falling from scaffolding or close calls due to not wearing a safety belt. For example, the VR safety education system called “Real HatⓇ” provided by Nishio Rent All reproduces in VR scenarios of realistic possible accidents—such as falls caused by scaffold defects, falling materials from cranes, or being crushed between a backhoe and a wall【※】. Participants “experience” an accident from the victim’s viewpoint, thereby realizing firsthand how dangerous a fall from height can be and leaving a strong impression to avoid repeating the same mistake. VR immersive education stands apart from lectures or videos and deeply engraves the importance of correct safety belt use and handrail installation. As a result, workers’ hazard prediction ability (quality of KY activities) and compliance with safe behaviors improve, helping suppress human error on site.

*(※The VR safety education system “Real Hat” allows participants to virtually experience various actual accident cases and discuss causes and countermeasures, contributing to heightened safety awareness. This system is also registered in the Ministry of Land, Infrastructure, Transport and Tourism’s NETIS new technology information provision system and is being adopted by construction companies nationwide.)*

As described above, the use of AI, IoT technologies, and VR is dramatically changing safety management for high-altitude work. Along with physical advancements in protective equipment such as full harnesses, creating digital systems that supplement “human inattention” and “lack of experience” could make zero fall disasters far from a mere dream.

Current Status and Challenges of Contact Accidents with Heavy Equipment

Another cause that often leads to serious accidents at construction sites is contact with heavy equipment. Accidents in which workers are involved in or struck by construction machinery such as backhoes (hydraulic excavators), bulldozers, cranes, and dump trucks are frequent. Among fatal accidents in the construction industry, these rank just after falls (although classification methods can make them less conspicuous in statistics), and many cases involve workers being run over or crushed in blind spots during machinery rotation or reversing.

Major causes of contact accidents with heavy equipment include the following.

• Operator blind spots: Large machinery has big bodies, and especially behind and to the sides there are extensive blind spots not visible from the cab. When heavy machinery is moved without a guide person, a worker or another vehicle can enter a blind spot and be struck. Tragic incidents often occur when a worker walking behind the machine while it is reversing or rotating is not noticed.

• Insufficient guidance and communication: In principle, a guide should be positioned when moving machinery with poor visibility, but in reality guide personnel are sometimes omitted because the movement is considered “just a short move,” or machinery is moved without clear signals. Miscommunication or poor coordination between the guide and the operator is a factor in contact accidents.

• Inadequate surrounding checks and sudden dashes: Focus on tasks can cause neglect of safety checks around machinery, or pedestrians may inadvertently enter the work area of heavy equipment. For example, a surveyor or materials handler in the operating area may be struck if timing with the operator does not align. There are also cases where a worker suddenly dashes out from a blind spot while a construction vehicle is driving within the site and is hit.

Against such equipment-related accidents, traditional measures have included thorough qualification and skills training, separation of people and machines through work planning, and deployment of guide personnel. Legally, operation of cranes and vehicle-mounted construction equipment requires qualifications, and regular safety education and machine inspections are mandated. Still, human error and inattention cannot be completely eliminated, and sites have faced a persistent dilemma of “if only the machine weren’t here…” or “if only people kept away…”.

However, in recent years solutions using the latest technologies addressing this “risk of human-machine contact” have emerged, yielding dramatic safety improvements. The next section examines advanced technologies and implementation examples for preventing contact accidents with heavy equipment.

Latest Technologies and Countermeasure Examples for Preventing Contact with Heavy Equipment

To reduce the risk of human-machine contact, the construction industry has begun adopting safety systems using IoT and AI. Examples of the latest countermeasures for preventing contact with heavy equipment are listed below.

• Vehicle-mounted AI cameras for blind spot monitoring and alarm systems: Systems that mount AI-capable cameras on the machinery itself to automatically monitor hazardous areas not visible to the operator—such as the rear and sides—have been put into practical use. A representative example is Shimizu Corporation’s vehicle-mounted safety monitoring camera “Kawasemi.” This system installs wide-angle cameras and image-analysis AI at the rear of machinery to continuously monitor nearly 360 degrees. When the AI detects a person or vehicle, it instantly determines the situation and activates warning sounds and a patrol lamp (stack light) if a worker enters within a set distance, notifying the operator. At the same time, loud sounds and lights alert workers around the machine so they mutually recognize the danger. This enables immediate detection even when a person enters the operator’s blind spot, and when combined with functions that automatically stop machinery, collisions can be prevented. In actual Kawasemi-equipped sites there have been reports that “close-call collisions during reversing dropped to zero,” with AI cameras acting as a “third eye” for machinery. Image-analysis AI is also evolving to read not only presence but worker posture and gaze; for instance, if a worker is facing away from the machine (not noticing it), a stronger-than-normal alarm may be issued. Such advanced functions help the AI “make workers notice” dangers and evolve into next-generation safety systems that prevent accidents.

• Proximity alarm systems (proximity alerts) and safety-zone management: Proximity detection systems that equip both machines and workers with sensors or transmitters to automatically sound alarms when coming within a set distance are also becoming common. For example, attaching UWB (ultra-wideband) or RFID tags to workers’ helmets or safety vests and installing receiving antennas on machinery. When a worker approaches within a set distance—such as 5 m (16.4 ft)—the machine cab buzzer sounds while the worker’s tag vibrates to warn them. This immediate mutual awareness greatly reduces near misses. These systems are particularly effective for night work with poor visibility or noisy sites, and some sites report dramatic reductions in near-miss reports after implementation. Additionally, position management systems using GPS or high-precision GNSS visualize on a digital site map the machine work area and human exclusion zones, and can send alarms to workers’ smartphones if they inadvertently enter dangerous zones. These proximity-alert and zone-monitoring systems function as a barrier to keep people away from machinery, contributing to fundamentally lowering the risk of contact accidents.

• Remote operation and automated construction to separate people and machines: The ultimate countermeasure to eliminate contact accidents is to ensure “people do not need to be present for dangerous machine work.” Under initiatives such as i-Construction and construction DX led by the Ministry of Land, Infrastructure, Transport and Tourism, remote control and autonomous operation technologies for heavy equipment are advancing. For example, systems have been demonstrated where a backhoe is operated via communication lines from a remote-control room in an office so excavation can proceed without anyone onsite, and unmanned dump trucks autonomously travel while AI automatically avoiding obstacles. Although still in limited stages of deployment, these systems are becoming realities for disaster recovery sites and dangerous slope-forming tasks where people do not ride or approach machinery. Widespread adoption of remote or automated construction would dramatically reduce contact accident risk. However, since human-machine collaboration is unavoidable in typical construction work today, interlock-type safety devices that automatically stop machinery when a person approaches—combining AI cameras and sensors with detection and alarms—are also being developed. If these technologies become standard equipment, safety around heavy equipment is expected to improve markedly.

Thus, a multi-layered safety net to prevent “person versus machine” accidents is beginning to be built using technology: AI continuously monitors and issues warnings, wearables and sensors watch the position relationship between people and machines, and ultimately unmanned construction keeps people out of harm’s way—mapping a concrete roadmap toward zero contact accidents with heavy equipment.

Regulations and Industry Initiatives Supporting Safety Management

Alongside technology adoption, laws and industry initiatives are also supporting safety management at construction sites. Japan’s Industrial Safety and Health Act and related legislation set detailed safety standards for high-altitude and heavy-equipment work, which employers are obligated to follow. For example, as mentioned earlier, requirements include “use of fall-arresting devices when working at heights of 2 m (6.6 ft) or more without a work platform,” “placement of qualified operators for crane operation,” “measures to prevent people from entering the operating radius of equipment such as backhoes,” and “regular voluntary inspections.” Because violations can lead to penalties, legal compliance is a fundamental prerequisite on sites.

Recent regulatory trends have strengthened safety measures—for example, the principle obligation to use full-harness-type safety belts (fully enforced in 2022), stricter requirements for rear visibility of construction machinery, and making efforts to provide workers with dangerous-experience education. The Ministry of Health, Labour and Welfare and construction industry organizations prepare a “Labor Accident Prevention Plan” every five years, setting clear numerical goals for the construction industry such as “reduce fatal accidents by 15% or more”, promoting zero-accident campaigns. In the 14th Labor Accident Prevention Plan from fiscal 2023 onward, construction is a priority industry with particular emphasis on preventing fall and machinery accidents.

At the corporate level, especially among major general contractors, efforts to realize “visualization of safety” and “cultivation of a safety culture” are active. Specific measures include systems for sharing near-miss cases across sites, invigorating safety meetings (hazard prediction activities: KY), and top management conducting site patrols to foster a corporate culture that prioritizes safety. Information exchange on new technologies is also occurring across the industry, and excellent safety devices and systems are being actively adopted. For instance, the adoption of worker-position management systems using IoT sensors and development of unsafe behavior detection systems using AI cameras are being pursued competitively by several major firms, with some collaborative research toward standardization underway.

Thanks to institutional improvements and voluntary corporate initiatives, the incidence of occupational accidents in construction has been steadily decreasing in the long term. Compared with 50 years ago, the number of fatal accidents has dropped to less than one-ninth. Nevertheless, construction still has a higher fatality rate compared with other industries, and safety measures cannot be delayed. Ensuring that “everyone working on site returns home safely” requires mobilizing laws, education, and technology to continue evolving safety management.

Improving Safety of Surveying Work with LRTK

The latest safety measures are not limited to high-altitude or heavy-equipment work. In fact, ancillary tasks such as surveying and as-built verification also benefit from new technologies that improve safety. A representative example is the simple surveying technology called LRTK, which combines a smartphone with a high-precision GNSS receiver. LRTK (short for Local RTK) is a revolutionary system that enables centimeter-level positioning with a palm-sized RTK-GNSS terminal attached to a smartphone, and it has attracted attention in civil surveying fields recently.

Traditionally, surveying and staking out in civil works required surveyors to approach near operating machinery to set up transits or GPS equipment and perform time-consuming measurements. During this time, survey personnel often had to be in close proximity to heavy equipment, carrying inherent contact risk. However, using LRTK allows quick acquisition of point coordinates with just a smartphone, dramatically shortening surveying time. For example, measuring staking points for road construction can be done quickly with a smartphone and a small GNSS device, so tasks can be safely completed within the short time that heavy machinery is on standby. Reducing the time surveyors spend in areas where machinery is operating directly reduces risk.

Moreover, LRTK includes AR (augmented reality) functions and photo-measurement features, enabling remote measurement of points without physically going to dangerous locations. For instance, on steep slopes or deep excavations—places dangerous to enter—one can point a smartphone camera from a safe distance to obtain coordinates of the target. This allows non-contact measurement of places that are unreachable or unsafe to approach, eliminating the risk of adopting unsafe postures or stepping into potential fall zones. Also, LRTK can instantly plot acquired positioning data on cloud-based maps, enabling the whole team to share which areas have been surveyed and which are dangerous. If you visualize no-entry zones and machine operation ranges on a high-precision GNSS-created work-area map, surveyors themselves can confirm safe positions on the screen and always maintain a safe distance from equipment while working.

Thus, LRTK’s simple surveying technology not only improves surveying productivity but also provides a secondary safety effect: greatly reducing the risk of surveyors contacting heavy equipment and maintaining safe distances. In practice, sites that have introduced LRTK report fewer near misses between surveying tasks and heavy equipment and feedback such as “we can safely operate machinery even during surveying.” Going forward, the use of such smart surveying devices will further spread, establishing a working style that visualizes hazardous areas while working efficiently.

Conclusion

Safety management in the civil engineering and construction industry is now at a major turning point, driven by technological progress and on-site ingenuity. We have reviewed the latest countermeasure examples—AI surveillance cameras, wearable sensors, VR training, remote monitoring systems, and alert devices—addressing the two major challenges of fall prevention and prevention of contact with heavy equipment. These introductions can compensate for the limits of human vision and plug the holes of human error, and quantitative results such as reductions in accidents and near-miss reports have been reported in many places. The effectiveness of technology is increasingly reflected in numbers, such as the reduction in fall accidents following full-harness mandates and continued zero heavy-equipment accidents after AI alarm system implementation.

Nevertheless, the final bastion for achieving true zero occupational accidents remains the safety awareness of each person working on site. No matter how excellent a device is, it is ineffective if not used. It is essential to advance safety management through the trinity of technology, education, and rules. Fortunately, under the trends of work-style reform and DX promotion, efforts to balance safety and productivity have become a major theme across the industry. Investments in smart safety management not only protect workers’ lives but also directly improve site reliability, and their priority is likely to rise further.

The path to zero accidents requires new ideas and continuous improvement. The latest countermeasure examples introduced here are only a part of that path, but by combining technological power and on-site capability, the goal of “zero occupational accidents” is becoming increasingly attainable. The evolution of safety management at construction sites continues, and the civil engineering and construction industry as a whole continues to challenge itself to create future worksites where all workers can work with peace of mind.