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Over the years, many fire and explosion accidents have occurred as a result of ignition sources generated by static discharge. In 2007, the U.S. Chemical Safety Board (CSB) investigated two accidents; one occurred due to poor grounding of plastic containers (mobile storage tanks) while filling them with flammable solvents (Figure 1) ； Another case occurred when a tank truck was unloading into a storage tank, due to poor grounding of the liquid level float inside the tank (Figure 2). Other accidents are caused by poor grounding or metal connections in storage tanks, mobile containers, tank trucks, and rail-mounted tank cars, or by the release of static electricity from the human body. Do you know? ★ Static charge is generated when two different materials come into contact and then are separated. Once static electricity is generated, the charge remains on the material unless it encounters a lower potential, at which point it discharges. The sparks generated during discharge have sufficient energy to ignite flammable vapors, flammable gases, and combustible dust clouds. ★ Static electricity can be generated when fluid flows through pipes, solids pass through pipes, or even air flows through pipes or gas delivery systems. ★ Mechanical conveying systems generate static electricity due to the contact between the rollers and the belt, especially when the belt slips. ★ Static sparks can be felt (as a sudden \"electric shock\"), seen (as a tiny blue arc of light), or heard (as a \"crackling\" sound of discharge). ★ Compared to conductive fluids such as water, alcohols, and propylene, non-conductive fluids like benzene, toluene, and naphtha are more prone to generating static electricity, and the process of charge dissipation is slower. ★ Poor grounding and improper metal connections of the hoses are common causes of static electricity. What can you do? ★ Before transporting any materials, it is essential to follow the factory’s procedures and regulations regarding grounding and metal connections. ★ It is necessary to ensure that the factory’s grounding/metal connection devices are regularly inspected and tested. ★ Check the grounding/metal connection device before each use to ensure it is in good condition and firmly connected to the container in a metal-to-metal manner. If this connection is damaged or the grounding is poor, please report it to your supervisor. ★ Inspect the hose before using it. In a damaged hose, the grounding wire inside it may also be disconnected. The electrical conductivity of the hoses should be checked regularly. ★ Containers made of non-metallic materials (such as plastic or glass) present difficulties in terms of grounding and metal connections. When using such containers, one must be extremely careful and follow the rules and regulations. If the required grounding device is not found, ask why it is absent. ★ If the solid material to be processed is contained in plastic bags or paper bags lined with plastic, consult an engineer to obtain the correct handling methods and advice on preventing static sparks. Controlling static electricity – a key step in reducing ignition sources!