What Not To Do While Welding?

Welding is a high-risk operation that requires strict compliance with safety regulations and operational standards. Even a small mistake during the process can lead to accidents such as fires, electric shocks, or poor weld quality. To ensure the safety of welders and the reliability of welding results, it is crucial to understand what actions should be avoided. The following lists key taboos during welding.​
1. Do not ignore personal protective equipment​
Personal protective equipment (PPE) is the last line of defense for welders against hazards, and any neglect of it may result in serious injuries.​
Never weld without wearing a welding helmet. The arc generated during welding emits strong ultraviolet and infrared radiation, which can cause "arc eye" (a painful inflammation of the cornea) if it directly irradiates the eyes. In severe cases, it may even lead to vision loss. Additionally, sparks and spatter from welding can splash onto the face, causing burns. Some welders may think that "short-term welding without a helmet is okay," but this idea is extremely dangerous-even a few seconds of arc radiation can damage the eyes.​
Do not wear inappropriate clothing. Synthetic fiber clothes (such as polyester and nylon) must not be worn because they melt quickly when exposed to high temperatures, sticking to the skin and causing severe burns. Loose-fitting clothes or clothes with cuffs and hems that are not tightened are also forbidden, as sparks can easily enter them and ignite the fabric. Similarly, gloves that are worn out, have holes, or are not flame-retardant should not be used. Without effective protection, the hands are vulnerable to burns from high-temperature workpieces or electric shocks from accidental contact with live parts.​
Avoid neglecting foot protection. Welding sites often have heavy objects such as metal workpieces and equipment. Wearing ordinary shoes instead of steel-toe safety shoes may result in foot injuries if objects fall. Moreover, the ground may be slippery due to oil stains or water, and non-slip safety shoes can prevent slips and falls.​
2. Do not operate with faulty equipment​
Using damaged or malfunctioning welding equipment is a major hidden danger that can cause electric shocks, equipment damage, or even fires.​
Never use a welding machine with a damaged power cord. A cracked or exposed power cord insulation layer may lead to direct contact between the human body and the live wire, resulting in electric shock. Similarly, loose plugs or sockets with poor contact can cause abnormal heating, increasing the risk of fire. Some operators may wrap the damaged part with tape temporarily, but this is only a stopgap measure and cannot replace proper repair or replacement-tape may melt under high temperatures, losing its protective effect.​
Do not ignore problems with the welding torch or cable. A blocked welding torch nozzle will disrupt the gas flow (for gas-shielded welding) or cause arc instability, leading to weld defects such as pores. A loose contact tip may cause excessive resistance and heating, even burning the torch. Welding cables with broken insulation or internal wire strands should not be used. Not only do they risk electric shock, but the increased resistance can also cause the cable to overheat, potentially igniting nearby flammable materials.​
Avoid using gas cylinders that are not up to standard. Gas cylinders (such as argon, carbon dioxide, or acetylene cylinders) with expired inspections, rusted valves, or damaged pressure gauges are extremely dangerous. Using such cylinders may result in gas leaks-flammable gases like acetylene can explode when mixed with air and exposed to an open flame, while inert gases like argon can cause suffocation in confined spaces if leaked in large quantities. Additionally, never knock or collide with gas cylinders, as this may damage the pressure relief device and trigger an explosion.​
3. Do not neglect the welding environment​
The welding environment directly affects operational safety and weld quality. Ignoring environmental risks can lead to accidents or substandard welds.​
Never weld in poorly ventilated enclosed spaces without protection. Welding fumes contain harmful substances such as heavy metals (chromium, nickel) and toxic gases (nitrogen oxides, phosgene), which can cause respiratory diseases, metal fume fever, or even long-term health issues like lung cancer if inhaled in large quantities. For example, stainless steel welding produces high concentrations of chromium and nickel fumes, which are carcinogenic. Even in open spaces, prolonged welding without proper ventilation (such as in a narrow corner) can cause fume accumulation.​
Do not work near flammable or explosive materials. Welding sparks can fly up to 10 meters away and remain ignitable for several seconds. Placing gasoline, paint, sawdust, or other flammable items near the welding site is like leaving a time bomb. Even seemingly harmless materials like rags soaked in oil can catch fire when exposed to sparks. Some operators may think that "keeping a small distance is enough," but wind or air flow can carry sparks further, igniting distant flammables.​
Avoid welding on wet or conductive surfaces without insulation. Welding on a wet floor or directly on a metal workbench without an insulating mat increases the risk of electric shock. The human body is a conductor, and if it comes into contact with both the welding circuit and a grounded conductive surface, an electric current will flow through the body. Similarly, do not touch the workpiece and the welding torch with both hands at the same time during welding-this creates a path for current to pass through the chest, which is more dangerous than passing through the arms.​
4. Do not violate material handling and welding process rules​
Improper handling of welding materials or non-compliance with process requirements will not only affect weld quality but also may cause safety hazards.​
Never use mismatched welding materials. Using the wrong welding rod or wire for the base metal will lead to weld failure. For example, using a carbon steel welding rod to weld stainless steel will result in poor corrosion resistance of the weld, and using a low-strength welding rod for high-strength steel will make the weld the weak point of the structure, which may break under load. Additionally, do not use damp, rusted, or expired welding rods. Damp low-hydrogen welding rods are prone to producing hydrogen-induced cracks in the weld, while rusted welding wires will introduce impurities into the weld pool, causing pores and slag inclusion.​
Do not skip pre-welding material preparation. Welding on a base metal with uncleaned surfaces (covered with rust, oil, paint, or oxide scales) will prevent the weld metal from fusing properly with the base metal, resulting in defects such as incomplete fusion and pores. For thick workpieces that require beveling, omitting the beveling process will lead to insufficient penetration, reducing the strength of the welded joint. Some operators may think that "a little rust won't matter," but in critical applications (such as pressure vessels), such defects can lead to leaks or even explosions.​
Avoid random adjustment of welding parameters. Welding current, voltage, and travel speed are determined based on the material, thickness, and welding method. Increasing the current excessively may cause burn-through (for thin materials) or overheating of the base metal, leading to grain growth and brittleness. Reducing the current too much will result in insufficient penetration. Arbitrarily changing the voltage can cause arc instability-too high a voltage leads to spatter, while too low a voltage makes the arc sticky, affecting weld formation. Some welders adjust parameters based on "experience" without referring to process specifications, which is risky, especially for high-quality requirements.​
5. Do not ignore post-operation safety​
Safety work does not end with the completion of welding. Neglecting post-operation steps may cause accidents such as fires or equipment damage.​
Never leave the work site immediately after welding. The welded workpiece and surrounding materials may remain at high temperatures and can ignite flammables even after the arc is extinguished. It is necessary to stay for at least 15-30 minutes to check for smoldering fires. For example, sparks that fall into sawdust or fabric may smolder for a period before bursting into flames. Additionally, do not stack combustibles near hot workpieces-even if they are not in direct contact, radiant heat can ignite them.​
Do not forget to turn off equipment and close gas valves. Leaving the welding machine powered on for a long time may cause overheating of internal components, especially if there is a fault in the cooling system. Unclosed gas valves can lead to slow gas leaks, which may accumulate to dangerous concentrations over time. For acetylene cylinders, even a small leak can form an explosive mixture with air. After use, always confirm that all power switches and gas valves are closed tightly.​
Avoid improper handling of welding waste. Spent welding rods, slag, and metal scraps should not be discarded randomly. Hot slag can ignite garbage, and sharp metal scraps may cause cuts. They should be collected in designated containers and disposed of after cooling.​
In summary, avoiding these forbidden actions during welding is essential to ensure operational safety and weld quality. Welders must always maintain a sense of responsibility, strictly abide by safety regulations and process requirements, and never take chances with dangerous behaviors. Only by doing so can accidents be prevented and reliable welding results be achieved.