5 Types of Accidents in Confined Spaces and 9 Safety Management Measures (Continued)

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Work in confined spaces is a key aspect of enterprise safety management. Although it isn’t particularly difficult, accidents do occur frequently during such operations. Today, we will introduce the types of accidents that may happen in confined space work, as well as several measures for ensuring safety in these operations. I. Types of accidents that are prone to occur in confined space operations 1. Object strikes: Many entrances to confined spaces are equipped with work platforms. During operations, due to a lack of safety awareness among the workers and inadequate supervision by supervisors, object strike injuries can occur while transferring tools or opening manhole covers, tank lids, etc. 2. Poisoning or asphyxiation: Most confined spaces require regular access for maintenance, cleaning, and inspections. Connected to these devices are numerous pipes and valves; if safety measures are not implemented, blind plates are not used, valves leak, replacement and ventilation are inadequate, or the oxygen concentration is not within acceptable limits, it creates an opportunity for toxic and harmful substances as well as asphyxiating gases to accumulate in the confined space, leading to poisoning or suffocation of the workers. There are also some manholes, cellars, septic tanks, etc., where, due to the long-term action of fermenting bacteria, toxic gases are produced and accumulate, leading to poisoning of workers. 3. Falls from heights, mechanical injuries: The working conditions in confined spaces are quite complex; for example, cooling towers and polymerization reactors are equipped with nozzles, supports, mixers, as well as various other electrical drive devices. During operations, accidents such as falls from heights and mechanical injuries can easily occur due to operators’ mistakes, incomplete safety equipment, or environmental factors such as wind and high temperatures. 4. Electric shock: When workers enter confined spaces to carry out tasks such as welding to repair leaks, they may suffer electric shock injuries due to factors such as high humidity in the space leading to leakage in electrical cables, the use of faulty leakage protectors or improperly selected ones, as well as damaged insulation on welding cables. 5. Explosion: Due to poor ventilation, flammable gases resulting from the evaporation of harmful substances in confined spaces continue to accumulate there. When these gases reach their explosive limit, they can explode upon contact with an open flame, causing damage to people and facilities. II. Safety management measures for work in confined spaces: During maintenance and repair tasks in confined spaces, it is necessary to properly handle all relevant work permits. Effective control measures must be implemented for each hazardous task. The project leader, supervisors, and safety officers at all levels must fulfill their respective responsibilities to ensure that these safety controls are in place before work proceeds. 1. All pipes and valves that are connected to the outside world must be effectively isolated from it. Effective isolation of pipes can be achieved by inserting blind flanges or removing a section of the pipe; water seals or closing valves cannot be used for isolation. Before starting the work, all power supplies connected to the equipment must be disconnected, and a “Personnel Working” sign should be hung on the control buttons. 2. Before entering a confined space for work, ensure that the oxygen level is above 19.5%, and conduct thorough cleaning. When working in such spaces with equipment that has previously contained flammable, explosive, toxic, or harmful substances, it is necessary to purge the space with compressed air; work can only proceed after the air quality has been verified as satisfactory. Air should be continuously supplied into the confined space during the operation to prevent oxygen deficiency inside the tank. Conduct regular inspections; stop operations immediately in case of any abnormalities and evacuate personnel. When applying coatings with volatile solvents, conduct analysis once per hour and implement adequate ventilation measures. 3. During the work process, tools and equipment around the entrance of the confined space should be cleared promptly. If it is necessary to deliver such tools and equipment, they must be lowered using ropes; throwing them up or down is strictly prohibited. All personnel entering confined spaces must wear complete personal protective equipment. When entering spaces where cleaning and replacement requirements cannot be met, an isolated gas mask or air respirator should be worn. In flammable and explosive environments, explosion-proof lighting fixtures and tools should be used. 4. The lighting voltage in confined spaces should be a safe voltage of 36V or less; in humid or narrow containers, a safe voltage of 12V or less should be used. When using hand-held power tools with a voltage exceeding the safe level, a leakage protector must be installed as required. Temporary electrical wiring installations should be installed and removed in accordance with regulations to ensure good insulation of the wires. 5. The site should be equipped with appropriate first-aid supplies such as air respirators (oxygen respirators), fire-fighting equipment, and clean water. Persons entering confined spaces to work must be healthy individuals without any occupational contraindications; those who are under the influence of alcohol or suffering from illnesses are strictly prohibited from entering such spaces. 6. When working inside confined spaces, a dedicated supervisor must be assigned to oversee the operation; this supervisor must fulfill their duties strictly and must not leave the site at will. In the event that a worker faints, rescue actions can be carried out immediately. Working at heights in confined spaces constitutes a type of special high-altitude work; it is necessary to wear a safety belt, with the belt’s hook attached to an appropriate location (make sure not to attach it to moving machinery), in order to meet the requirements for proper attachment at a higher height. 7. When entering a confined space to carry out rescue operations, rescuers must take proper protective measures; they can enter the confined space to conduct rescue efforts only after ensuring their own safety. 8. It is prohibited to supply oxygen or oxygen-enriched air into confined spaces to prevent fire and explosion accidents. When using electrical welding equipment, the welding tools must be safe, reliable, and in good condition. When using gas welding and cutting equipment, they should be placed where they are needed, and taken out of the tank immediately after use; it is strictly forbidden to store them inside the tank. The welding machine must be equipped with a leakage protector; it should be kept dry and clean, and its power cables and grounding wires must meet the required standards. 9. When toxic and hazardous materials present in a confined space cannot be dealt with, it is necessary to obtain approval from the relevant authorities and take safe and reliable measures before entering the confined space to carry out work.