Never undertake these high-risk tasks without careful consideration

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During the production process, companies often arrange for their employees to carry out tasks with high safety risks, such as hot work, work in confined spaces, temporary electrical work, and work at heights. How to prevent risks during operations? Enterprises should strictly implement protective measures, and employees should follow procedures to minimize the risk of accidents and injuries. [Hot work] ☆ Hazards posed by flammable and explosive substances ☆ Hazards caused by leakage current (induced electricity) ☆ Inadequate spacing between gas cylinders or improper placement ☆ Defects in welding and gas welding tools ☆ Leakage of flammable materials or flying sparks ☆ Poor ventilation and lack of regular monitoring ☆ Insufficient emergency facilities or improper safety measures ☆ Significant changes in on-site conditions Safety key points: 1. Clean and replace the materials inside hot work equipment and pipelines; only proceed with the work after ensuring that they meet analytical standards. The storage tank should be filled with clean water or an inert gas for protection, while the equipment is protected by nitrogen and water vapor. Employees who perform welding work in confined spaces must obtain a permit for working in confined spaces. 2. Cut off the equipment pipes connected to the hot work equipment, seal them with blind plates, and obtain a permit for performing blind plate installation and removal operations. 3. Remove flammable materials around the hot work area; clean and seal nearby manholes, floor drains, trenches, cable ducts, etc. 4. The return wire for electric welding should be connected to the workpiece; it must not be connected to any other equipment, and it is prohibited from running through sewers (manholes). 5. For hot work at heights, a permit for working at heights must be obtained to prevent sparks from flying. For operations involving heights, blind flange removal/installation, and maintenance of piping equipment, the relevant work permits must also be obtained. 6. The distance between oxygen cylinders and dissolved acetylene cylinders shall be no less than 5 meters; the distance between them and any hot work site shall be no less than 10 meters. Cylinders must not be exposed to direct sunlight, and dissolved acetylene cylinders must not be placed horizontally. 7. Before carrying out hot work, welding and gas welding tools should be inspected to ensure they are safe and reliable. In the event of material leakage, cross-contamination, or a leak of flammable gases, welding operations must be stopped immediately. 8. When performing hot work indoors, open the doors and windows, cover surrounding equipment, seal any water leaks, and remove oil stains. No cleaning operations involving flammable substances should be carried out nearby; local forced ventilation measures may be employed. When interrupting hot work, no remaining embers must be left at the site. Before reigniting, it is necessary to check whether there have been any changes in the site conditions; if so, ignition shall not be carried out. 9. The interval between monitoring sampling and hot work must not exceed 30 minutes; the sampling points should be representative, and the analysis samples from special hot work operations should be retained until the work is completed. 10. The area where welding is carried out should be equipped with steam pipes, water pipes, fire extinguishers, etc., and the fixed foam fire extinguishing system should be brought into a pre-startup state. The fire supervisor should be familiar with the site environment, check that safety measures are in place, keep track of changes in operating conditions, and remain at the site. 【Work in confined spaces】☆ Unreliable isolation ☆ Mechanical injuries ☆ Risk of electric shock ☆ Poor ventilation and insufficient oxygen ☆ Inadequate protective measures ☆ Blocked access routes ☆ Lack of regular monitoring ☆ Involves other hazardous operations ☆ Foreign objects left inside equipment Safety key points: 1. Material, steam, and nitrogen pipelines connected to the equipment must be isolated using blind flanges, and a permit for installing/removing blind flanges must be obtained. 2. Carry out procedures for shutting down equipment power; cut off the power supply to the equipment; hang a “Do Not Close Switch” warning sign; and assign a dedicated person to supervise. 3. The oxygen content inside the equipment should be between 18% and 21%, and the temperature should be suitable for human operation. The ventilation openings of the equipment should be opened for natural ventilation. 4. Within 30 minutes before starting the operation, it is necessary to sample and analyze the gas inside the equipment; entry is permitted only after confirmation that it meets the required standards. Monitoring should be strengthened during the operation. 5. The lighting voltage inside the equipment should be less than or equal to 36 volts, and in humid or confined spaces, it should be less than or equal to 12 volts. Portable electric tools used with voltages exceeding the safe limit should be equipped with a residual current device. 6. When working in oxygen-deficient or toxic environments, employees must wear isolated respirators ； In flammable and explosive environments, explosion-proof lighting fixtures and tools should be used ； In corrosive environments such as those with acids and bases, appropriate corrosion-resistant protective gear should be worn. 7. The supervisor shall, together with the workers, check the safety measures and coordinate the communication signals ； The supervisor must maintain contact with the equipment at all times and must not leave their post ； The access routes for equipment should be kept unobstructed. 8. Outside the equipment, air respirators, fire-fighting equipment, clean water, etc. should be readily available. When entering the equipment to perform rescue operations, personnel must take proper protective measures. 9. In cases involving operations such as hot work, working at heights, and blind flange removal/installation, the relevant work permits must be obtained simultaneously. In the event of any significant changes in construction conditions, a new permit for confined space work must be obtained. 10. After the work is completed, no tools or other items shall be left at the site. 【Temporary Electrical Work】☆ Personnel violations ☆ Damaged cables ☆ Short circuits in distribution panels and boxes ☆ Damage to other facilities ☆ Fire and explosion ☆ Significant changes in working conditions Safety key points: 1. Workers must hold a certificate for safe electrical work. The overhead height of temporary electrical wiring shall be no less than 2.5 meters within the plant and no less than 5 meters above roads. Exposed wires shall not be used for temporary electrical wiring, and overhead lines shall not be strung on trees or scaffolding. 2. Dark pipes and underground cable lines should be equipped with direction markers and safety signs, and the burial depth should be greater than 0.7 meters. 3. Rain protection measures shall be taken for temporary on-site power distribution panels and boxes. Temporary electrical installations should be equipped with leakage protectors. 4. Temporary electrical equipment and wiring must meet the corresponding explosion-proof requirements. 5. In case of any significant changes in operating conditions, a new temporary electrical work permit must be obtained. [Work at heights] ☆ Unfamiliarity with the work environment ☆ Failure to use fall prevention and anti-slip equipment ☆ Facilities not meeting safety requirements ☆ Inadequate isolation and safety measures ☆ Poor lighting and poor communication ☆ Occupational contraindications ☆ Adverse weather conditions such as strong winds and heavy rain ☆ Risk of personnel falling or objects falling from heights ☆ Supervisors failing to fulfill their duties ☆ Key safety points for hot work and operations involving blind flange removal/installation. 1. Workers must undergo safety training, become familiar with the site environment and construction requirements, properly use fall prevention and anti-slip equipment, wear safety helmets, safety belts, and anti-slip shoes. Only after ensuring that all safety measures are in place may they commence work. 2. The erection of scaffolding and protective fences shall comply with relevant requirements. Ensure that the lighting conditions at the work site are good. When performing work at heights near electrical equipment, safety distance requirements must be met. 3. The supervisor should be familiar with the site environment, possess emergency response skills, remain at the site, ensure that safety measures are in place, and stay informed of any changes in operating conditions. When working at heights of over 30 meters, communication equipment should be provided, and a designated person should be assigned to oversee the task. 4. Tools, parts, etc. used for work at heights should be placed in tool bags; employees must not hold anything in their hands while moving up or down, and must not throw or pass tools, materials, etc. When stacking slippery or rollable tools on scaffolding, fall prevention measures must be taken. 5. No one is allowed to stand directly beneath areas where work at heights is being performed. When such work is carried out concurrently with other operations, personnel must ascend and descend via the designated routes; vertical movement up and down is prohibited. If vertical work is necessary, reliable isolation measures must be taken. 6. Persons with occupational contraindications or poor health conditions shall not perform work at heights. 7. In cases involving hazardous operations such as hot work or blind flange removal/installation, the relevant work permits must also be obtained. If there are significant changes in the construction conditions, a new high-altitude work permit must be obtained. 8. In case of adverse weather conditions such as heavy rain, dense fog, or winds above force 6, work at heights shall be suspended. 【Circuit disconnection work】☆Unclear signs and poor communication of information☆Lack of appropriate safety measures or inadequate implementation of such measures☆Inadequate cleanup at the work site☆Changes made without approval☆Safety considerations for multiple types of hazardous operations: 1. Before starting the work, the construction party should install traffic barriers and signs at the points where the circuits are disconnected, to guide passing vehicles to take alternative routes. The circuit breaking work permit must be approved by the relevant authorities. 2. Fences and traffic warning signs shall be set up at the construction site; warning lights shall be hung at night. The construction contractor shall assign safety inspectors to ensure the unimpeded flow of traffic on the highway in case of emergencies; construction materials must not be randomly piled up on the road surface. 3. After the work is completed, the site should be cleaned up; the barriers, traffic cut-off signs, fences, warning signs, and warning lights installed at the site and at intersections should be removed, and the matter should be reported to the traffic management authorities. Traffic can be resumed only after on-site inspection and verification. 4. Circuit-breaking work must be carried out in accordance with the details specified in the circuit-breaking work permit. The construction unit shall not change the scope of the work without permission, nor shall it expand the work area or alter the location of the work. If the hot work is not completed within the specified time, a new hot work permit must be obtained. 5. In cases involving multiple hazardous operations, relevant work permits shall be obtained simultaneously. In the event of any significant changes in construction conditions, a new permit for road closure must be obtained. [Excavation operations] ☆Pipelines and cables are damaged ☆Collapses occur ☆Personnel suffer from poisoning or falls ☆Safety measures are inadequate ☆Operations involving heights, road closures, etc., are hazardous. Key safety points: 1. Verify that protective measures for power cables and battery cables have been implemented. Verify that protective measures for underground water supply and drainage pipelines as well as process pipelines have been implemented. When excavating near underground utilities, care must be taken; mechanical tools such as grapples shall not be used. Construction must be carried out in accordance with the construction plan, and relevant units such as transportation, fire services, and work safety supervision must be notified. 2. When multiple people are digging simultaneously, a certain safety distance should be maintained. Excavation should be carried out from top to bottom; the method of “digging from the bottom up” shall not be used. The excavated soil must not block sewers and manholes. When digging ditches or pits without slopes, supports must be installed; when digging below the water table, drainage measures must be taken. 3. Workers must wear safety helmets. No one shall stand or walk on the upper edges of pits, grooves, wells, and ditches. 4. Fences, warning lines, warning signs, and warning lights at the work site must be set up as required. Equipped with combustible gas detectors and toxic medium detectors. Protective measures for personnel entry, exit, and evacuation must be in place. Sufficient lighting is required for night work. 5. In cases involving hazardous operations such as working at heights or road closures, the relevant work permits must also be obtained. [Blind flange operations] ☆ Defects in blind flanges ☆ Leakage of hazardous substances ☆ Open flames and other ignition sources ☆ Operational errors ☆ Poor ventilation ☆ No personnel supervision on site ☆ Inadequate safety measures ☆ Improper emergency response ☆ Complex and high-risk operations ☆ Significant changes in operating conditions Safety key points: 1. The material of the blind flange must be suitable; its strength should be calculated accordingly. High-pressure blind flanges must pass flaw detection tests. Additionally, the blind flange should be easy to identify and install/remove. 2. Before removing or installing blind flanges, the pressure in the pipeline should be reduced to atmospheric pressure or slightly positive pressure ； It is prohibited to perform two or more blind flange removal and installation operations on the same pipeline simultaneously ； The gas temperature should be below 60°C; operators must not face the direction from which hazardous substances might emerge, and they should wear appropriate personal protective equipment. 3. When working in flammable and explosive areas, no welding or burning operations shall be carried out within 30 meters of the work site. Explosion-proof lighting and tools must be used; it is not allowed to strike pipelines, flanges, etc. with iron tools. 4. When removing and installing multiple blind flanges, operations must be carried out according to the blind flange layout diagram and numbering system. The person in charge of the operation shall provide unified direction; at each location where a blind flange is removed or installed, a sign should be placed to indicate its position. 5. Enhance natural ventilation; local forced ventilation measures may be adopted. 6. During operations, a dedicated supervisor must be present. The supervisor should be familiar with the site environment, possess relevant safety knowledge and emergency response skills, ensure that all safety measures are properly implemented, maintain communication with the operating personnel, and stay informed of any changes in operating conditions at all times. For tasks that are complex and highly dangerous, personnel from other relevant departments should also be present on site and prepared for emergency situations. 7. When carrying out hazardous operations such as hot work, work in confined spaces, or working at heights, relevant work permits must also be obtained. In case of any significant changes in operating conditions, a new permit for blind flange removal and installation must be obtained. 【Lifting Operations】☆Operation without a license☆Confused command☆Incomplete plans☆No barriers or warning signs☆Poor lighting conditions☆Adverse weather conditions☆Failure to strictly follow the “Ten Prohibitions for Lifting”☆Operations involving broken circuits☆Operations at heights☆Significant changes in operating conditions Safety points: 1. Personnel involved in lifting operations and those in charge of giving commands must receive professional training and work with valid licenses. The site should be under the unified command of a designated person, with clear signals. 2. There should be a comprehensive lifting plan, warning lines should be established, and safety signs placed to prevent unauthorized personnel from entering. 3. Sufficient lighting must be available at the site during night operations. Operations should be halted in case of severe weather conditions such as heavy rain, dense fog, or winds of force 6 or above. 4. Strictly enforce the \"ten rules against lifting\": Do not lift when the command signals are unclear or confusing; do not lift when the load is excessive or the weight of the object is unknown; do not lift when lifting heavy objects at an angle; do not lift when the lighting is insufficient and the object cannot be seen clearly; do not lift when there are people standing under the heavy object; do not lift when the object is buried underground; do not lift when the object is not securely fastened, the ropes are knotted, or the ropes are not in proper condition; do not lift sharp objects without proper padding; do not lift when the safety devices are malfunctioning; do not lift when the height of the heavy object exceeds that of a person’s head. 5. If it is necessary to block road traffic, a road closure permit must be obtained. If working at heights is required, a high-altitude work permit must be obtained. If there are significant changes in the construction conditions, a new work permit must be obtained.