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The \"Five Provisions on Preventing Dust Explosions in Enterprises\" (**Order No. 68 of the State Administration of Work Safety**) apply to workplaces involving explosive dusts in industries such as manufacturing and trade, where materials like coal powder, aluminum powder, magnesium powder, zinc powder, titanium powder, zirconium powder, flour, starch, powdered sugar, milk powder, blood meal, fish bone meal, textile fiber powder, wood powder, paper powder, rubber and plastic powder, and tobacco are used. Among them, the first one is a regulation regarding factory buildings, the second one is a regulation on dust prevention, the third one is a regulation on fire prevention, the fourth one is a regulation on water resistance, and the fifth one is a regulation concerning systems. Article 1: It is necessary to ensure that the workplace meets the required standard specifications; it is strictly prohibited to locate it in illegal multi-story buildings, factories that do not meet safety distance requirements, or within residential areas. Interpretation of the provisions: 1. The buildings in workplaces where dust explosions pose a risk must meet the requirements of the \"Code for Fire Protection Design of Buildings\" (GB50016-2006) and the \"Safety Regulations for Dust Explosion Prevention\" (GB15577-2007). The factory building should be designed as a single-story structure with a lightweight roof. If the factory building is designed as a multi-story structure, it should have a frame structure; adequate blast vents must be provided in the surrounding walls, the strength of the partitions between floors must be sufficient to withstand the impact of explosions, and there must be separate safety exits for floors above the first floor. 2. The buildings in areas where dust explosion hazards exist should be separated from other buildings or structures, and the fire safety distances between them shall comply with the relevant provisions of GB50016. 3. Given the immense destructive power and wide-ranging hazards of dust explosions, it is strictly prohibited to locate workplaces with a risk of dust explosions in residential areas. Article 2: Ventilation and dust removal systems must be designed, installed, used, and maintained in accordance with standard specifications. Dust must be monitored as required and cleaned regularly during each shift. Operations are strictly prohibited when the dust removal system is shut down or when dust levels exceed the specified limits; in such cases, production must be halted and personnel removed from the area. Explanation of the provisions: 1. The ventilation and dust removal system can effectively reduce the dust concentration in the workplace and minimize dust accumulation there. Enterprises must design, install, operate, and maintain dust removal systems in accordance with regulations such as GB15577, GB50016, the \"Guidelines for Explosion Protection of Dust Collectors in Areas at Risk of Dust Explosions\" (GB/T17919-2008), and the \"Code for Design of Heating, Ventilation and Air Conditioning\" (GB50019-2003). 2. The dust removal systems in areas where dust explosions pose a risk must be installed in a relatively independent manner, divided into sections or zones according to the provisions of GB15577. Dust collection hoods must be installed at all dust-generating points, and it is prohibited for the pipelines of different dust removal systems to be interconnected to prevent chain reactions that could lead to explosions. 3. To ensure the safe and reliable operation of the dust collector, enterprises must, in accordance with GB/T 17919, monitor indicators (parameters) such as the pressure difference between the inlet and outlet of the dust removal system, as well as the temperatures at the inlet, outlet, and ash hopper. The dust concentration is measured in accordance with the provisions of \"Determination of dust in workplace air – Part 1: Total dust concentration\" (GBZ/T192.1－2007). 4. When dust accumulation is detected in the pipes of the dust removal system and within the dust collector housing, the cause must be identified, and thorough cleaning must be carried out promptly and in accordance with standards. Negative pressure vacuuming should be used during cleaning to prevent dust from flying. If blasting is necessary, nitrogen, carbon dioxide, or other inert gases should be used as the cleaning gas source to prevent dust explosions during the cleaning process. 5. Dust accumulated in the workplace is a major factor that can trigger chain explosions and large-scale blasts; enterprises should establish a regular dust cleaning system in accordance with GB15577 requirements, and carry out timely, thorough, and standardized cleaning of the work area at the end of each shift. When cleaning dust, measures should be taken to prevent it from being raised again; it is best to use negative pressure for cleaning, and the use of compressed air for blowing is strictly prohibited. 6. Dust explosions can easily occur during the downtime of the dust removal system and when dust accumulates heavily at the work sites (with the thickest layer exceeding 1 mm). Therefore, operations must be stopped immediately and personnel evacuated from the work sites. Article 3: Explosion-proof electrical equipment must be used in accordance with relevant standards, and measures such as lightning protection and anti-static protection must be implemented to ensure that equipment and facilities are properly grounded. The presence of any kind of open flame in the work area, as well as the improper use of working tools, is strictly prohibited. Interpretation of the provisions: 1. In areas where dust explosions are a risk, the generation of any kind of open flame or spark must be strictly prohibited. The use of explosion-proof electrical equipment is a reliable measure to prevent electrical sparks. Explosion-proof electrical equipment must be installed and used in accordance with the \"Code for Design of Electrical Installations in Explosive and Flammable Environments\" (GB50058-1992) and the \"Safety Regulations for Electrical Explosion Protection in Hazardous Areas\" (AQ3009-2007). 2. The enormous discharge current generated during lightning discharges has a great destructive power, and it can also easily trigger dust explosion accidents. Facilities (buildings) in areas where dust explosions are a risk must be equipped with lightning protection systems in accordance with the \"Code for Design of Lightning Protection of Buildings\" (GB50057-2010), and must be properly grounded. 3. Activities such as the transportation, discharge, mixing, stirring, filtering of powders, as well as the crushing, grinding, and screening of solids, can all generate static electricity, which may lead to dust combustion or explosion. All metal equipment, device enclosures, metal pipes, supports, components, parts, etc., in areas where dust explosions pose a risk, must be provided with anti-static grounding in accordance with GB15577 and the General Guidelines for Preventing Static Electricity Accidents (GB12158-2006). All metal pipe joints (such as flanges) should be bridged. 4. Sparks are generated by collisions and friction between metal components. In areas where dust explosions are a risk, the use of iron tools that can generate sparks through collision is prohibited; explosion-proof tools must be used during maintenance work. Especially in areas where metal powders such as aluminum, magnesium, titanium, and zirconium are present, effective measures should be taken to prevent friction and impact with stainless steel, which could generate sparks. Article 4: Waterproof and moisture-proof facilities must be installed for the production, collection, and storage of metal dusts such as aluminum and magnesium; spontaneous combustion of the dusts when exposed to moisture is strictly prohibited. Explanation of the provisions: The metal dusts that are flammable when exposed to moisture and listed in the Catalogue of Hazardous Chemicals include lithium, sodium, potassium, calcium, barium, magnesium, magnesium alloys, aluminum, aluminum-magnesium alloys, zinc, etc. During the production, collection, and storage of these metal dusts, measures to prevent spontaneous combustion of the powder must be taken in accordance with GB15577 standards; waterproof and moisture-proof facilities should also be installed to prevent the dust from catching fire when exposed to moisture, which could lead to dust explosions and fires. Article 5: Safety operating procedures and labor protection regulations must be strictly enforced. It is prohibited for employees who have not undergone adequate training or who fail to wear labor protection equipment such as dust masks and anti-static gear as required, to report for duty. Explanation of the provisions: 1. Safety operating procedures mainly include the use and maintenance of ventilation and dust removal systems, dust cleaning operations, grinding and polishing tasks, inspection and maintenance work, and hot work operations. 2. In accordance with the Work Safety Law and GB15577, the principal persons in charge of enterprises in workplaces where there is a risk of dust explosions, as well as work safety management personnel, must possess the appropriate knowledge and management skills related to dust explosion prevention in work safety. Enterprises must provide all employees with education on work safety and dust explosion prevention, disseminating knowledge regarding dust explosion prevention and relevant safety regulations, so that employees can understand the level of hazard in areas prone to dust explosions within the enterprise as well as the necessary preventive measures ； Employees working in positions with a risk of dust explosions must receive specialized training in safety techniques and related procedures, and only after passing the examinations may they be allowed to take up their duties. 3. Prolonged inhalation of dust by on-site workers can easily lead to pneumoconiosis or silicosis. On-site workers must wear and use dust-protective PPE as required before starting work. To prevent static electricity generated by friction between human skin and clothing, as well as between pieces of clothing, employees working in environments where dust explosions are a risk are prohibited from wearing synthetic fiber clothing that tends to generate static electricity. They must wear anti-static clothing in accordance with GB15577 and the \"Rules for Selecting Personal Protective Equipment\" (GB/T11651-2008).