Risk Analysis of Eight High-Risk Operations (Part 2)

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This post was last edited by yinkuilin6868 on 2015-11-17 at 10:42. Risk analysis for hot work: 1. Flammable, explosive, and hazardous substances ① The materials inside the equipment and pipelines used for hot work have been cleaned and replaced, and the results of the analysis show they are suitable. ②When working on the storage tank, remove flammable materials, and fill the tank with clean water or use an inert gas for protection. ③Internal protection of the equipment (nitrogen, water vapor). ④When working with fire inside the tower, soak asbestos cloth and lay it between adjacent tower trays as a barrier. ⑤To perform welding work in a confined space, it is necessary to obtain a \"Confined Space Work Permit\". 2. If Mars enters other equipment, or if flammable materials get into the equipment where welding is to be carried out, cut off the pipelines connected to that equipment and install blind plates as barriers; label them, and obtain a permit for blind plate installation and removal. 3. Flammable materials are present around the area where welding is to be carried out. ① In addition to removing the flammable materials around the welding site, any flammable substances in nearby sewers, floor drains, ditches, cable trenches, etc., should also be removed and those areas sealed off. ②When working with fire in cable trenches, remove any flammable gases and liquids from the trench; if necessary, isolate both ends of the trench. 4. The hazard of leakage current (induced electricity): The welding return circuit should be connected to the welded piece, not to other equipment, and it is prohibited to pass through sewers (wells). 5. For welding work at location ① on Mars, obtain a \"High-Altitude Work Permit\" and take measures to prevent sparks from flying. ②Pay attention to the direction in which the sparks fly, and rinse the area where they land with water. 6. Insufficient spacing or improper placement of gas cylinders: ① The spacing between oxygen cylinders and acetylene cylinders dissolved in liquid form should be no less than 5 meters, and the distance between each of these cylinders and the area where welding or cutting takes place should be no less than 10 meters. ②Gas cylinders must not be exposed to direct sunlight, and acetylene cylinders must not be placed in a horizontal position. 7. Before carrying out welding or cutting operations with faulty tools, these tools must be inspected to ensure they are safe and reliable; it is not allowed to use them in a defective state. 8. During the operation, and in cases of leakage of flammable materials or during welding work, if there is any spillage of materials, cross-contamination, or presence of flammable gases, welding must be stopped immediately. 9. Poor ventilation: ① When performing welding or similar operations indoors, the doors and windows should be opened; surrounding equipment should be covered, sink traps should be sealed, oil stains should be removed, and no cleaning activities using flammable substances such as solvents should take place in the vicinity. ②Local forced ventilation is used ； 10. Unscheduled monitoring: ① The interval between sampling and hot work must not exceed 30 minutes; if this interval is exceeded or if the hot work is interrupted for more than 30 minutes, sampling and analysis must be carried out again. ②The sampling points should be representative, and the analysis samples from special hot work operations should be retained until such work is completed. ③During welding operations, when work is interrupted, no remaining embers should be left at the site. Before resuming welding, it is necessary to carefully check whether there have been any changes in the conditions at the site; if there have been changes, welding must not proceed. 11. Inadequate supervision: ① The person in charge of monitoring the fire should be familiar with the site environment and ensure that safety measures are properly implemented; they must possess relevant safety knowledge and emergency response skills, remain in contact with their post, stay aware of any changes in operating conditions, and stay at the site at all times. ②The fire watcher extinguishes any spilling sparks at all times; if anything abnormal is detected, they immediately inform the person performing the work to stop and contact the relevant personnel to take action. 12. Insufficient emergency facilities or inadequate measures: ① Fire-fighting tools should be available at the site where welding work is carried out (such as steam pipes, water pipes, fire extinguishers, sand, iron shovels, etc.). ②Set the fixed foam fire extinguishing system in the pre-startup state. 13. In cases involving combinations of hazardous operations for which appropriate safety measures have not been implemented, when carrying out hazardous tasks such as working inside reactors, at heights, removing or installing blind flanges, or maintaining pipeline equipment, the relevant operation permits must be obtained simultaneously. 14. In the event of significant changes in the construction conditions, a new ‘Level 2 Hot Work Permit’ must be obtained. Risk analysis for working in confined spaces 1. Unreliable isolation ① The pipelines for materials, steam, and gases connected to the equipment should be isolated using blind flanges, and a \"Blind Flange Installation/Removal Permit\" must be obtained. ②Dismantle the relevant pipelines. 2. For mechanical injuries, proceed with the procedures to shut down the equipment, cut off its power supply, hang a \"Do Not Close\" warning sign, and assign a dedicated person to supervise the process. 3. After the replacement is completed and found to be unsatisfactory, samples are taken for analysis until they meet the required standards. 4. Insufficient oxygen: The oxygen content inside the equipment is 18–21%. 5. Poor ventilation: ① Open the ventilation holes of the device to allow natural ventilation. ②Forced ventilation is used. ③Wear an air respirator or long-tube mask. ④Air is supplied through ducts; prior to ventilation, it is necessary to analyze and verify the contents within the ducts as well as the air source. The introduction of oxygen for oxygenation is strictly prohibited. ⑤The temperature inside the equipment must be suitable for personnel to work in. 6. Unscheduled monitoring: ① Gas sampling and analysis within 30 minutes before starting work must be conducted; entry into the equipment is permitted only if the results are satisfactory. ②The sampling points should be representative. ③During the operation, regular monitoring should be strengthened, and the operation must be stopped immediately if any abnormalities are detected. 7. Hazards of electric shock: ① The lighting voltage inside equipment should be less than or equal to 36V; in humid or confined spaces, it should be less than or equal to 12V. ②When using hand-held power tools with a voltage higher than the safe level, leakage protectors must be installed as required. 8. Inadequate protective measures: ① Wear a self-contained breathing apparatus in environments with low oxygen levels or toxic substances ； ②In flammable and explosive environments, use explosion-proof low-voltage lighting fixtures and tools that do not generate sparks; it is prohibited to wear fiber-based fabrics ； ③In corrosive environments such as those with acids and alkalis, it is necessary to wear corrosion-resistant protective gear, including slag removal suits, acid-resistant boots, acid-resistant gloves, and safety goggles. 9. Unobstructed access: There should be no obstacles in the equipment’s inlet and outlet areas that could prevent people from entering or exiting. 10. Improper supervision: ① Before entering the equipment, the supervisor should check the safety measures together with the workers and establish a unified communication signal ； ②The supervisor must remain in contact with the equipment at all times and must not leave their post ； ③The supervisor uses a safety rope to tie the worker while they are working. 11. Insufficient emergency facilities or inadequate measures: ① Appropriate first-aid supplies such as air respirators, fire-fighting equipment, and clean water are available outside the equipment ； ②When carrying out rescue operations inside equipment in case of an accident, rescuers must take proper protective measures before entering the equipment to carry out the rescue. 12. In cases involving combinations of hazardous operations for which appropriate safety measures have not been implemented, relevant operation permits must be obtained simultaneously when carrying out hazardous tasks such as welding, work at heights, or removing and installing blind flanges. 13. In the event of significant changes in the construction conditions, a new Confined Space Work Permit must be obtained. 14. Foreign objects left inside the equipment: After work is completed inside the equipment, it is necessary to thoroughly check both the inside and outside of the equipment to ensure that no tools or other items are left behind. Risk analysis for temporary electrical work 1. Illegal operations ① Workers must hold a certificate for safe electrical work. ②The overhead height of temporary power lines should be no less than 2.5 meters inside the facility, and no less than 5 meters on roads. ③All temporary electrical wiring must not use exposed wires. ④Temporary power lines, being overhead lines, must not be installed on trees or scaffolding. 2. For damaged cables buried in concealed ducts or underground cable lines, “direction” markers and safety signs should be installed, with the burial depth of the cables being greater than 0.7 meters. 3. For temporary power supply at the site of short circuits in distribution panels and boxes, such panels and boxes should have rain protection measures. 4. Preventing damage to facilities: ① Temporary electrical installations should be equipped with leakage protectors. ②Electrical equipment, circuit capacity, and load must meet the required standards. 5. Temporary electrical equipment and wiring used to prevent fires and explosions must meet the corresponding explosion-proof requirements. 6. In the event of significant changes in working conditions, a new ‘Temporary Electricity Use Permit’ must be obtained. Risk analysis for road closure operations: 1. Lack of clear signage and poor communication can disrupt traffic and lead to accidents. ① Before starting the work, the construction party should set up traffic barriers and signs at the roads to be closed, indicating to vehicles the alternative routes to take. ② Once the traffic management authorities approve the ‘Road Closure Permit’, relevant departments such as the dispatch team should be informed immediately. 2. During construction, the absence of appropriate safety measures or their inadequate implementation can lead to traffic accidents or injuries. ① During road closure work, the construction party is responsible for setting up barriers and traffic warning signs at the construction site; red warning lights should be installed at night. ② When carrying out road closure work, the construction party should assign safety inspectors to ensure that the road remains accessible in emergency situations. ③During circuit disconnection work, the construction party must not pile up construction materials randomly. 3. After the work is completed, if the site is not cleaned thoroughly, it can impede traffic and lead to accidents. ① After circuit interruption work is finished, the construction party shall be responsible for cleaning up the site, removing the barriers, circuit interruption signs, fences, warning signs, and red warning lights installed there and at intersections, and reporting this to the traffic management authorities. ②After conducting an on-site inspection, the traffic management authorities notify the relevant units that the road closure work is complete and that traffic can be resumed. 4. Unapproved changes can lead to accidents.① Road closure operations must be carried out in accordance with the details specified in the Road Closure Permit; it is strictly prohibited to alter or lend this permit, as well as to change the scope of the work, expand the area involved, or move the location of the work without authorization. ②If the disconnection work is not completed within the time specified in the Disconnection Work Permit, the entity that requested the disconnection must proceed with the procedures again. 5. In cases involving combinations of hazardous operations for which appropriate safety measures have not been implemented, relevant operation permits must also be obtained when carrying out hazardous tasks such as work at heights or earthwork. 6. In the event of significant changes in the construction conditions, a new ‘Circuit Disconnection Work Permit’ must be obtained.