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I. Selection of human body static electricity discharge devices: During safety inspections of enterprises that produce, store, or use flammable and explosive hazardous chemicals, it was found that there are two options for human body static electricity discharge devices – one is a simple type, and the other is an explosion-proof type. The structure of a simple human body static discharge device is very straightforward; its feature is that it can discharge static electricity, but it does not have explosion-proof capabilities. Its structure consists of a release ball that is welded to a release rod; the release rod is then connected to an electrostatic ground. This type of human body electrostatic discharge device can be used in industrial and commercial enterprises where there are requirements for electrostatic safety, in order to eliminate the hazards caused by human body electrostatic charge. However, when used in enterprises that produce, store, or handle flammable and explosive hazardous chemicals, it becomes quite dangerous. Such static discharge devices can only release static electricity; they do not have the capability to prevent static discharge from generating sparks. An explosion-proof human body static discharge device is a safety device specifically designed for use in flammable and explosive hazardous areas (such as industries involving chemicals, petroleum, pharmaceuticals, storage, and transportation). Its primary function is to safely and gradually discharge the static electricity accumulated on the human body before people enter such areas, thereby preventing fires or explosions caused by static discharge. 1 Its structural design must meet two core requirements: one is the safe discharge of static electricity – ensuring that it is released into the ground in a spark-free, gradual, and controllable manner. Second is intrinsically safe/explosion-proof: its structure does not act as a source of ignition, and it meets the corresponding explosion-proof rating requirements (such as E*b IIC T4 Gb / E*b IIB T4 Gb, etc.). 2 The typical structure of an explosion-proof personal static discharge device consists of the following key components: first is the touch ball/touch pad, which is usually made from materials with excellent electrical conductivity, wear resistance, and corrosion resistance, such as stainless steel (304/316) or special conductive engineering plastics. Its function is for a person to touch this area with the palm of their hand (skin contact is required) before entering the explosion-proof area. It is the entrance for human body static electricity to enter the discharge device. Its design requirements are a smooth surface and a large enough area to ensure reliable contact; it is usually hemispherical or a circular flat plate. The second is the current-limiting resistor (a key safety component): it is located in the conductive path between the touch ball and the grounding terminal. Its material and properties feature high-precision, highly stable, low-temperature-coefficient non-inductive resistors (such as metal film resistors and wire-wound resistors). Its resistance value is usually around 1 MΩ (megohm) (for example, 1 MΩ ± 5%). This resistance value is a critical parameter that has been determined through rigorous calculations and standard specifications. Its primary function is to limit the discharge current, keeping the peak current during discharge in the human body below safe levels (usually required to be less than 5 mA). This ensures that even in environments with highly flammable gases, the energy released during discharge is not sufficient to ignite explosive mixtures. It also prolongs the discharge time, allowing static electricity to be released slowly and steadily into the ground, thereby preventing the occurrence of sparks resulting from sudden high-current discharges. It is key to the intrinsically safe nature of human body static discharge devices, and it serves as the core component for achieving an \"intrinsically safe\" (Type i) explosion-proof design for such equipment. Third is the grounding terminal/ground wire: its material is usually brass or stainless steel. Its function is to connect grounding wires or grounding busses that meet the specified requirements (low resistance, reliability). The requirement is that the grounding resistance must be low enough (generally, the resistance to the grounding grid should be < 10Ω) to ensure that static electricity can be smoothly discharged into the ground. Fourth is the explosion-proof enclosure: its material is usually high-strength metal (such as cast aluminum, stainless steel) or high-strength engineering plastics (which must meet anti-static and flame-retardant requirements). Its function is mechanical protection, serving to safeguard internal components from physical damage. Its explosion protection requirements are determined by the specific explosion protection type (such as intrinsically safe type d, increased safety type e, intrinsically safe type i, or combined types); the enclosure design must meet the corresponding standards. Fifth is the status indicator: its type is generally an LED light. Its functions are power indicator and release status indication (advanced feature). Some intelligent release devices are equipped with sensing circuits; when a person touches the touch ball and effectively discharges static electricity, an indicator light will turn on or change color (for example, from red to green), providing visual feedback to confirm that the discharge process has been completed and that the grounding path is intact. Its explosion protection requirements mean that the control circuits and their components must also meet the overall explosion protection standards of the equipment (such as by using intrinsically safe circuit designs). Sixth is the mounting base/support: it is made of metal (such as stainless steel) or high-strength plastic. Its function is primarily to securely mount the releaser body in a designated location (such as at a door, pillar, or wall). It usually features a fixed hole or slot design. Seventh are the internal connection wires: reliable, low-resistance wires are required to ensure a continuous, low-impedance conductive path between the touch ball, the current-limiting resistor, and the ground terminal. The connection should be firm and reliable to prevent loose connections. II. Requirements for the selection of human body static electricity discharge devices based on standards and specifications 1. Article 4.2.3.8 of the \"General Requirements for Preventing Static Electricity Accidents\" (GB 12158-2024): Use static electricity eliminators to quickly neutralize static electricity: ——Explosion-proof static electricity eliminators should be used in areas where there is a risk of static electricity; ——To eliminate static electricity from materials that are not conductive to static electricity, different types of static electricity eliminators should be employed depending on the specific conditions at the site; ——Static electricity eliminators should be installed at the points on the charged objects where the electric potential is highest. 2. Article 12.1.4 of the «Code for Construction and Quality Inspection of Anti-static Engineering» (GB 50944-2013): Explosion-proof static elimination devices shall be used in flammable and explosive areas. 3. Article 4.2.2 of the «Code for Safety and Health Design of Chemical Enterprises» (HG 20571-2014): The anti-static design of chemical plants shall adopt corresponding anti-static measures based on the requirements of the production process, the characteristics of the working environment, and the properties of the materials used. Article 4.2.10: In workplaces where static electricity hazards may occur, personal anti-static protective equipment shall be provided. At the entrances of areas where fire and explosion prevention measures are critical, devices for discharging static electricity from the human body should be installed. 4. Article 10.2.1 of the \"Technical Specifications for Antistatic Safety in Oil and Gas Fields\" SY/T7385-2024: Installation location: Intrinsically safe human body static charge eliminators shall be installed in areas prone to explosion, such as those for oil and gas gathering, transportation, processing or purification, refining, storage, loading and unloading, as well as fuel and gas filling (see Appendix A). 5. Article 4.1 of the \"Safety Specifications for Intrinsic Safety Type Human Body Static Electricity Eliminators\" SY/T7354-2017: Inventories, processing, or purification of oil and gas, refining, storage, transportation, loading and unloading, fueling, and gas filling facilities shall be equipped with intrinsic safety type human body static electricity eliminators (see Appendix A). In general, in enterprises that produce, store, or use flammable and explosive hazardous chemicals, effective and safe discharge of human body static electricity must receive high attention from enterprise managers. When selecting human body static electricity eliminators, explosion-proof types should be used, and the appropriate explosion-proof rating should be chosen based on the type of flammable and explosive substance involved.