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Safe electricity use at construction sites is an important aspect of ensuring safe production. Based on the electricity usage situations at several of our company’s construction sites, this article discusses the characteristics, shortcomings of electricity use at such sites, as well as the measures that should be taken. I. Characteristics of electricity use at construction sites: 1. High degree of temporariness. This is mainly determined by the construction timeline; smaller projects take only a few months to complete, while larger ones take several years. After the project is finished, some of the electrical installations have to be removed, so such installations cannot be as sturdy and secure as permanent ones. 2. Large fluctuations in electricity consumption. As a project progresses through construction, its electricity consumption varies significantly at different stages. 3. Poor environment and high risk. The construction site itself has a poor environment, and with multiple types of work being carried out simultaneously, there is a constant risk of coming into contact with power lines; a slight carelessness can easily lead to electric shock accidents and injuries. 4. The equipment has high mobility. As the project progresses, electrical equipment and hand-held power tools change frequently, coupled with the carelessness of the operators. Lack of emphasis on electricity can lead to greater hazards. II. Shortcomings: 1. There is insufficient attention paid to the management of electricity usage during construction; the relevant safety and technical documentation is inadequate. Electricians on site are considered special-category workers who require thorough training and must hold valid certificates to be qualified for this work. However, most construction sites do not have full-time electrical operators, and those that do often lack proper knowledge and rely on experience in their work. Some sites focus solely on economic benefits and are reluctant to invest in proper inspections and maintenance of electrical systems. Management personnel also fail to provide detailed or targeted instructions regarding electrical procedures, and there are no records of such instructions. 2. No special temporary power supply organization design is prepared. According to regulations, on construction sites with 5 or more electrical devices or a total capacity of over 50 KV, a separate temporary electrical construction plan must be prepared. However, some people think this is not necessary and simply connect wires and install equipment based on experience, resulting in unreasonable electricity usage. 3. The vast majority of electrical installations do not use the TN-S system, and the neutral grounding protection is not standardized. Many on-site personnel have a vague understanding, thinking that as long as electricity is supplied, the machine starts running and the lights come on, that’s sufficient. Regardless of whether it is safe or not, the three-phase four-wire system is still used, with grounding protection employed in some cases. In some construction sites, although a three-phase five-wire system is used, there is only 1–2 points for repeated grounding, or no repeated grounding at all. In such cases, the working neutral wire and the protective neutral wire are used interchangeably, and the protective neutral wire is not marked with green and yellow colors to distinguish it. Additionally, the leakage protectors used are of inferior quality; their parameters do not match the requirements, and their wiring is incorrect. Some of the leakage protectors used on these sites have not been certified by the relevant authorities, and many of them are of poor quality. The leakage current threshold of the leakage protectors installed in the switch boxes is often above 30 MA. Moreover, leakage protectors are connected on the power side of the isolating switch, and single-phase electrical equipment is not equipped with leakage protectors. The protective neutral wire passes through a leakage protector, which results in no operation; the main distribution box is not equipped with a leakage protector, and only primary protection is available. 5. Protection measures against external electrical hazards are inadequate; when the distance between construction sites and external power lines is less than the specified safe distance, protective measures are often not implemented. Workers work at great risk to their lives. In some cases, although protective measures are in place, they are not effective enough – there are no warning signs on the protective barriers, and the protective materials used are not up to standard, making it difficult to prevent hard objects from passing through. There are large gaps, or protection is only provided in certain areas, leaving potential hazards. 6. The wire material is of poor quality; insulated wires are from unreputable manufacturers, resulting in frequent cases of insulation damage and leakage current. The insulation quality is inadequate, and the cross-sectional area of the wires is small. The protective neutral wire is made of aluminum and is not laid alongside the phase wires. 7. The cable lines are laid openly on the ground, without any apparent pattern. Some were buried, but at a shallow depth; they were not covered with 50-mm-thick fine sand on top and bottom, nor were they compacted with solid materials. Cable joints lacked junction boxes, resulting in poor water resistance. 8. The distribution boxes and switch boxes have poor quality and many potential hazards. The enclosures for distribution boxes and switch boxes are made of wooden structure, offering poor protection against rain and fire ； Construction materials are piled up around the box, making operation and maintenance extremely inconvenient ； In some cases, switch boxes are not used; the switches are simply nailed to wooden boards, with the switches exposed ； Some enclosures are too small, with the electrical devices inside packed closely together, which makes operation extremely inconvenient and unsafe ； The labeling on distribution boxes and switch boxes is unclear, which can lead to incorrect operations ； The wires leading out of the box are arranged haphazardly; some come from the side, some from the top, and others directly through the box door, making it very easy for rainwater to enter the box ； The locations of the distribution panels and switch boxes are not properly set; the switch box is more than xml:namespace prefix = st1 ns = \"urn:schemas-microsoft-comffice:smarttags\" / 3 meters away from the electrical equipment, while the distribution panel is more than 30 meters away from the switch box ； The box is missing terminal blocks; most of the wires are “chicken-foot” type ； Electrical appliances are installed on wooden boards; the boxes contain a lot of clutter. The appliances lack poles or corners, or have few screws and nuts, as well as missing switch covers. Multiple switches are used simultaneously, and electrical devices are connected in a messy manner. 9. The wiring of on-site lighting is arbitrary. Most worksite shacks are low in height; those under 2.4 meters do not use a safety voltage of 36V or less ； The lighting wires and fixtures are casually tied to wires, frames, pipes, or nails; the wires are damaged and aged, resulting in poor insulation ； The lighting circuit does not use a dedicated circuit; there is no knife switch, and it is connected directly to the equipment’s knife switch. III. Measures taken: 1. Strengthen on-site electricity management, improve relevant technical records, assign dedicated electricians to carry out work with proper certifications, enhance maintenance and inspection activities, keep accurate records, and establish corresponding documentation. 2. Develop a specialized electrical planning design based on the characteristics of the construction site; understand the current situation there, consider all aspects thoroughly, design carefully, and make well-organized arrangements to produce a design that provides practical guidance. 3. Strictly implement the principle of “three-level power distribution and two-level protection”. A three-level power distribution system comprising a main distribution box, distribution boxes, and switch boxes is implemented at the site. Both the main distribution box and the switch boxes are equipped with leakage protectors for a two-level protection system, ensuring hierarchical control. 4. Implement a standardized three-phase five-wire system to reduce electrical hazards. In most construction sites, electricity is supplied by power providers, and a three-phase four-wire system is commonly used. The site should have its own main distribution box; from the power side of the first-level leakage protector, a protective neutral wire is derived through repeated grounding, ensuring that the working neutral wire and the protective neutral wire are properly separated. Repeated grounding is carried out at several points, both at the end of the protective neutral wire and at intervals of about 50 meters along its length, so that the resistance value of each grounding point does not exceed 10 ohms. The enclosures and casings of electrical equipment are connected in parallel to the protective neutral wire using multiple copper wires. 5. For devices such as leakage protectors, distribution boxes, switch boxes, and electrical appliances, appropriate parameters should be selected based on the performance of the electrical equipment, and these devices must be used correctly. 6. Proper protection must be provided against external electricity. Whenever external electrical lines are closer than the specified safe operating distance, protective measures must be taken and appropriate plans implemented to ensure electrical safety. 7. Properly lay the cables. For sites that use cable lines, the cables must be buried underground, and the covering material must meet the required standards. Junction boxes should be installed, and the cables must run straight along the walls at the appropriate height. 8. Pay attention to on-site lighting to reduce the risk of electric shock. The lighting circuits and power circuits are strictly separated, proper protective grounding is implemented, safe voltage is used, and leakage protectors are installed.