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Dust prevention measures: Other technical and management measures that should be adopted in various industries and specialties (such as refractory materials, casting, coal transportation, glass production batching, etc.), in accordance with the requirements of relevant industry and specialty standards. Limit and suppress the dispersion of dust and particulates: 1) Use enclosed pipelines for transportation, enclosed automatic (mechanical) weighing systems, and enclosed equipment for processing, to prevent dust from escaping ； For dust sources that cannot be completely sealed, facilities such as semi-enclosed hoods or isolation chambers should be used as much as possible, under conditions that do not interfere with operations, in order to isolate and reduce contact between dust and the air in the workplace, confining the dust to a localized area and thereby minimizing its dispersion. An air screen formed by the flat jet of air blown out from slit nozzles can isolate the air environments on both sides of the air curtain, preventing harmful substances from spreading from one side to the other. 2) Suppress dust generation caused by positive pressure by methods such as reducing the height difference of materials, appropriately lowering the inclination of chutes, isolating air currents, reducing the amount of induced air, and creating spaces (channels). 3) For hydrophilic, weakly sticky materials and dust, measures such as humidification, spraying, and vapor spraying should be employed as much as possible; this can effectively reduce the generation and dispersion of dust during processes such as loading/unloading, transportation, crushing, screening, mixing, and cleaning ； Spraying in the factory building helps to agglomerate and settle airborne dust. High-voltage electrostatic dust suppression devices can effectively prevent the spread of metal dusts such as gold, tungsten, copper, and uranium, as well as non-metallic dusts like coal, coke, grains, and furs, as well as dust from welding and blasting, in open dust sources found in industries such as metallurgy, building materials, mining, machinery, food processing, and light industry – including vibration screens, crushers, belt conveyor transfer points, mine tunnels, and fur processing facilities. 4) To eliminate secondary dust sources and prevent further dust generation, the design should arrange elements in a way that minimizes areas where dust can accumulate. The floors and walls should be smooth and flat, with rounded corners to facilitate cleaning ； Use a negative pressure cleaning device to remove dust that has dispersed and settled on the floor, walls, components, and equipment ； In workplaces where dust with high levels of contamination such as carbon black is present, or where large amounts of dust accumulate, waterproof floors, walls, ceilings, components, and water washing should be used to remove the accumulated dust. It is strictly prohibited to clean accumulated dust using purging. 5) Powdered additives that cause significant pollution (such as carbon black powder in the rubber industry) should be transported in small bags; they should be fed and processed along with their packaging to prevent the spread of dust. When designing ventilation and dust removal systems, it is necessary to take into account the characteristics of the manufacturing process as well as the requirements for dust removal. By utilizing wind pressure and thermal pressure differences, air flow can be organized effectively (through the use of intake and exhaust vents, skylights, baffles, etc.), thereby making full use of natural ventilation to improve the working environment. When natural ventilation is insufficient, comprehensive or partial mechanical ventilation and dust removal systems should be installed. 1) Total mechanical ventilation refers to the ventilation and air exchange of the entire factory building. It involves continuously introducing clean, fresh air into the workshop, diluting the concentration of harmful substances in the air there (including dust), and expelling the polluted air outside, so that the concentration of harmful substances in the indoor air remains below the maximum allowable levels specified by standards. It is generally used in workplaces where there are open, mobile sources of harmful substances. When several toxic vapors or several irritating gases are released in a room at the same time, the total volume of ventilation required should be calculated as the sum of the ventilation amounts needed to dilute each harmful substance to its respective maximum allowable concentration. When several other harmful substances are emitted simultaneously, the calculation is based on the maximum value of the air exchange rates required to dilute each of them to its respective maximum allowable concentration. 2) Local mechanical ventilation involves ventilating and exchanging air in certain specific areas of a factory, thereby improving the working conditions in those areas. Local mechanical ventilation includes local supply air and local exhaust air. Local air supply involves delivering clean, fresh air to specific work areas in order to ensure that the quality of the working environment there meets the specified standards. It is primarily used in workplaces where it is difficult to keep the concentration of harmful substances at acceptable levels, and where the work areas are fixed in location and occupy a small space ； Local exhaust ventilation involves installing local exhaust hoods at the locations where harmful substances are generated; these hoods use airflow to capture the harmful substances and expel them outside, thereby preventing them from spreading to the work area of the workers. It is the most effective method for removing harmful substances through ventilation, and it is currently the most effective approach used in industrial production to control dust dispersion and eliminate the hazards caused by dust. In local ventilation, clean, fresh air should generally flow first through the work area, then toward the source of harmful substances, and finally be expelled through exhaust vents; air containing harmful substances should not pass through the breathing zone of the workers. Management measures such as dust prevention education, regular inspections, enhanced maintenance of dust prevention facilities, and periodic health checks are implemented for education, inspection, and equipment maintenance. Preventive measures for occupational health related to processes and materials: To prevent occupational hazards, it is necessary to give priority to using processes and materials that are harmless or have minimal hazards, in order to reduce the leakage and spread of harmful substances ； Where possible, use production equipment (production lines) that feature closed, mechanized, and automated processes, as well as automatic monitoring and alarm systems, interlock protection mechanisms, and safety emission devices, in order to achieve automatic control, remote operation, or isolated operation. Try to avoid or minimize direct contact by operators with equipment and materials that generate harmful factors during the production process. Dust prevention measures: Processes and materials – Choosing processes that generate little or no dust, and using materials that are harmless or have minimal hazards, are the fundamental ways to eliminate or reduce the risks posed by dust. For example, replacing dry production processes with wet ones (such as using wet spinning for asbestos instead of dry spinning, water grinding instead of dry grinding, hydraulic or electro-hydraulic cleaning instead of mechanical cleaning, and using water mist arc gouging, etc.); replacing mechanical screening with closed-air classification; replacing sand casting processes with die-casting or investment casting processes; replacing water glass sand with resin sand; using materials with low or no free silica content instead of those with high silica content; avoiding the use of toxic substances such as manganese and lead; and using or reducing process methods that generate respirable dust (dust with a size of less than 5μm). In dust-filled workplaces where, due to manufacturing processes and technical limitations, ventilation and dust removal systems fail to meet the requirements set by occupational health standards, operators must wear personal protective equipment such as dust masks (as well as work uniforms, helmets, respirators, and glasses) ；