Electrostatic earthing protection is a crucial aspect of ensuring safe production in the coatings industry. Production accidents caused by inadequate earthing, excessive feeding speeds, or operator error during manual feeding are all too common. Using automated equipment for feeding can effectively prevent such accidents.
January 2026 – A fire suddenly broke out at a factory in Yuhuan City, Taizhou, Zhejiang. Thanks to a prompt response, the incident resulted in no significant property damage or casualties.
Cause of the accident: An employee was using a solvent to clean a product when some of the solvent accidentally splashed out and ran onto the floor. The employee subsequently bent down to pick up an item; at the moment their body made contact with the floor, a static electricity spark was generated, igniting the solvent on the floor.
19 November 2025 – A fire broke out in the production workshop of a company in Anhui, resulting in one fatality.
Cause of the accident: A member of staff at the company generated a static electricity spark whilst carrying out material extraction operations, which ignited the material inside a tonne drum, causing the fire.
Materials and organic solvents used in chemical enterprises, such as petrol, ethanol, acetone and toluene, are mostly flammable liquids or gases. When the vapours of these materials mix with air, they readily form explosive mixtures. Furthermore, during the production, storage and transport of chemical materials, static electricity accumulates when they come into contact with equipment, pipelines, reactors and other objects through friction or impact. Furthermore, during the conveyance of certain powdered materials, friction between particles can also generate static electricity; should a discharge occur, this may trigger combustion or explosion incidents.
In some enterprises, equipment and pipework are not fitted with static electricity earthing as required, or the earthing systems are ageing or damaged, preventing static electricity from being promptly dissipated into the ground.
Lack of electrostatic bonding. Where electrostatic bonding is not installed between flanges as required, a potential difference exists on either side of the flange, preventing the smooth conduction of static electricity and increasing the likelihood of discharge.
Operators failing to follow operating procedures, such as failing to check the effectiveness of electrostatic earthing devices before loading or unloading materials, failing to discharge static electricity from the body before entering flammable and explosive areas, and handling materials in a rough manner, leading to severe friction between the materials and equipment.
The General requirements for preventing electrostatic accidents (GB 12158—2024), which came into force on 1 January this year, cover static electricity protection in workplaces where there is a risk of static‑induced ignition (or explosion). This includes requirements for static earthing in workplaces, personal static electricity protection measures, precautions for the storage and transport of materials, amongst others. The scope of application covers workplaces such as the petroleum and petrochemical industries, petrol stations and mines, as well as any other locations where static electricity generated by personnel operations may pose a risk of fire or explosion; it does not apply to the prevention of static electricity hazards associated with gunpowder, explosive materials, electrical pyrotechnics or fireworks.
1. Optimisation of Process Design: In the design of production processes, optimisation should be undertaken to minimise impact, friction and separation processes; for relevant materials, the contact area and pressure should be reduced, the frequency of contact minimised, and the speeds of movement and separation lowered.
2. Humidity Control: Where process conditions permit, the local relative humidity in storage and production areas for flammable and explosive materials should be raised to 50% or above; however, this should not be applied in Zone 0 explosive gas atmospheres.
3. Optimisation of Material Combinations: For materials that generate static electricity upon contact, those positioned close to one another in the electrostatic series should be selected, or materials that generate positive and negative charges should be appropriately combined.
1. Installation of electrostatic earthing devices: In accordance with standards, install approved electrostatic earthing devices and carry out regular inspections to ensure that the earthing resistance meets the requirements (not exceeding 100 Ω). Common earthing methods are as follows:
2. Installation of additional electrostatic bonding: At connection points between metal equipment and between pipes, measures such as wire bonding or metal flange connections shall be taken to ensure good electrical conductivity. Where metal flange connections are used without additional bonding wires, there shall be two or more bolts securing the connection. Where the resistance between any pair of flanges or threads exceeds 0.03Ω, wire bonding shall be carried out.
3. Installation of static eliminators. Static eliminators shall be installed in areas prone to static electricity, such as the outlets of material conveyance pipelines, the inlets of powder silos, and loading/unloading bays. Static eliminators shall be installed at the points on charged bodies where the potential is closest to the maximum.
1. Liquid materials: When filling large containers, such as tankers, with hydrocarbon liquids, bottom filling shall be the preferred method. If top filling is unavoidable, the filling pipe should extend into the tank to a distance of no more than 200 mm from the tank bottom. During top filling, the flow velocity should be limited to within 1 m/s whilst the filling pipe is not submerged in the liquid; once the inlet is submerged by 200 mm, the flow velocity may be gradually increased, but the maximum flow velocity should not exceed 4.5 m/s to minimise static electricity generation.
Containers made of non-conductive materials must not be used to hold flammable insulating liquids; metal containers and funnels must be bonded and earthed; when filling anti-static containers, all metal components must be bonded to the filling pipeline.
2. Solid materials: Select dissipative conveyor belts and conductive pulleys in accordance with the hazard zone classification; choose dissipative drive belts that meet the resistance limit requirements for the relevant hazard zone classification.
3. Gaseous and powdered materials: Implement one or more of the measures shown in the diagram. When using inerting technology, monitor oxygen concentration and ensure gentle filling to prevent the entrainment of dust, etc.
1. Standardise personnel attire: Operators in flammable and explosive environments (including other personnel entering the work area) must wear anti-static footwear and anti-static clothing as required, and are strictly prohibited from putting on or taking off clothing whilst on duty. Where the floor or footwear is not adequately earthed, local static protection measures such as wrist straps must be used.
2. Training and Management: Conduct regular anti-static training covering legislation, standards, operating procedures and drills. Develop a static electricity hazard control plan specifying hazards, causes, control measures and training schedules. Identify static-sensitive materials, hazardous areas and processes; establish an inspection mechanism to rectify potential hazards promptly. Place prominent signage in areas with static electricity hazards, indicating the hazard level, boundaries, earthing points and protective requirements.
In liquid dosing station equipment, the electrostatic earthing system comprises the earthing of pipework, raw material drums, receiving drums and the cleaning system. All pipework in contact with materials must be earthed, and the inner lining of hoses must be made of materials that comply with electrostatic dissipation standards; furthermore, their electrostatic dissipation performance must be tested and certified by a testing body prior to use.
At the raw material end, ensure that static grounding measures are in place for storage tanks; static grounding should utilise soft copper wire with a cross-sectional area of no less than 6 square millimetres to ensure electrical conductivity. Where possible, metal piping should be used; moving mechanical parts of the equipment should avoid metal-to-metal impact, and where this cannot be avoided, copper should be selected as the material for contact surfaces. Once the equipment has been installed, the resistance between the parts in contact with the material and the grounding busbar must be measured to ensure that all parts are properly earthed. Additionally, the discharge rate must be controlled.
Although static electricity is invisible, it can be a matter of life and death; prevention lies in the details, and consistency is key. Only by giving equal weight to technological measures and regulatory standards, and by ensuring that every operation and every grounding point is properly implemented, can we truly build a robust ‘firewall’ for safe production in the coatings industry and uphold the fundamental principle of ‘the people first, safety first, life first’.
If you would like to learn more about static electricity or how our dispenser protects against it, please do not hesitate to contact us. We are available 24 hours a day.
