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Generally speaking, explosion-proof electrical equipment refers to a type of electrical device used in areas where hazardous gases and vapors are present. In chemical production, various hazardous gases and vapors are often encountered. In areas where such substances are present, selecting the appropriate explosion-proof electrical equipment in accordance with relevant specifications, standards, and regulations is an important measure to ensure safe production as well as to prevent explosions and fires. Explosion-proof electrical appliances are mainly divided into the following six categories. Explosion-proof control cabinets: These mainly include lighting distribution boxes used to control lighting systems, and power cabinets used to control power systems. Most of these products have a modular structure and can control up to 12 circuits. Their housings are mostly made of cast aluminum alloy, some are welded from steel plates, and a very small number have housings made of insulating materials. Its interior mainly consists of circuit breakers, contactors, and thermal relays. It is composed of switches, signal lights, buttons, and other components; the manufacturer can also choose to include additional items as per the user’s requirements. The explosion protection rating can reach up to IICT6. Incidentally, explosion-proof automatic switches, explosion-proof knife switches, and fuses are also commonly used in certain control applications to open and close circuits in power or lighting distribution systems, though in this case they function as a single unit. Therefore, these products are also classified under this category. Explosion-proof starters: This category includes products such as manual starters, electromagnetic starters, reversible electromagnetic starters, autotransformer step-down starters, Y–Δ transformation step-down starters, and feed switches. As terminal control devices, explosion-proof starter products typically involve one starter controlling one motor, and they are products that are widely used in large quantities. Its outer shell is usually made of cast aluminum alloy or steel plate. Its interior generally consists of components such as contactors (air-type or vacuum-type), motor protection systems, signal lights, buttons, and autotransformers, and it usually features local control, remote control, and automatic control functions. Some products also come equipped with a circuit breaker as a main switch, making them more complete. Explosion-proof control switches: There is a relatively high demand for such products in the market, which is why there are many manufacturers of them. These mainly include small explosion-proof devices such as lighting switches, changeover switches (combination switches), limit switches, and pull-cord switches. The explosion protection rating of these products can reach level II CT6. Their explosion-proof enclosures are typically of composite structure, made by die-casting aluminum alloys; however, a few manufacturers use enclosures made from other materials. These products are characterized by their small size, single internal components, low technical complexity, simple structure, and ease of production. Explosion-proof master control electrical apparatus: Master control electrical apparatus are switching devices used to close or open control circuits in order to issue commands or carry out programmed controls. Such explosion-proof electrical devices mainly include control buttons and operation levers. The housings for explosion-proof control buttons are generally manufactured by injection molding using polycarbonate, glass fiber-reinforced unsaturated polyester resin, or ABS plastic; in some cases, they are also formed by die-casting aluminum. Its general structure features a enhanced safety enclosure containing flame-proof components, and it also offers corrosion protection; its explosion protection rating can reach Class II C. The control column mainly consists of a main box, a wiring box, and support pillars. Their main box and wiring box are either made as one unit or separately, each with its own advantages. Its material is basically made of cast aluminum alloy. The interior is composed of various components such as instruments, changeover switches, buttons, and signal lights. It can be combined according to different needs. Explosion-proof junction boxes: Electrical equipment must be connected to the power supply network through wires or cables in order to function as part of a system and carry out its intended tasks. However, its connecting wires or cables cannot be infinitely long, and there are many points during the connection process where wires need to be branched using series and parallel connections. This will inevitably lead to external leakage at the joint area, making accidents likely. Explosion-proof junction box products are designed to address such issues, in order to further ensure safe production. Such products include junction boxes, wiring boxes, conduit boxes, suspension boxes, distribution boxes, etc., whose housings are mainly made of cast aluminum alloy. As required, there are numerous inlet and outlet connection devices, and the box is equipped with terminal blocks for making connections or branching. Most of these products are manufactured as explosion-proof or increased-safety types, with varying sizes and significant differences; their explosion protection rating can reach Class II C. Explosion-proof lighting fixtures: Lighting measures must be implemented in any workplace or environment, and this applies equally to areas containing various explosive gases. Due to their wide range of applications in various production areas, explosion-proof lighting products are manufactured in large quantities. There are a wide variety of such products with diverse specifications, but they can generally be classified into categories such as those for lighting, signage, signaling, and portable use. In terms of light source types, they include incandescent lamps, self-ballasted mercury lamps, high-pressure sodium lamps, metal halide lamps, dysprosium lamps, and fluorescent lamps. Structurally, there are even more variations, including ceiling-mounted, wall-mounted, recessed, portable, and cantilevered types. From an installation perspective, explosion-proof lighting fixtures can be installed at angles ranging from 30° to 90°. In terms of power, it can range from dozens of watts to several hundred watts. The installation height ranges from the ground level up to several meters. It can be said that explosion-proof lighting fixtures are the products with the highest production volume and widest usage among all explosion-proof electrical products. Furthermore, due to its specific functions, it results in high wear and a high frequency of replacements. These products come in a wide variety of structural shapes, but in terms of explosion-proof performance, they are mainly of the flameproof type. The casing is usually made of cast aluminum alloy, and they are capable of meeting the various lighting and display requirements of users in areas classified as below Class II C.