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MIG (Metal Inert Gas) welding is an arc welding process in which an electric arc forms between a continuous solid wire electrode and the workpiece, heating the workpiece metal, and joining them together. Together with the wire electrode, shielding gas like argon and carbon dioxide are fed through the welding gun, protecting the weld pool from contaminants in the air. The term MIG welding was changed to GMAW, or Gas Metal Arc Welding, but most people still refer to the process with its old name.
MIG welding has enabled people from all walks of lifefrom hobbyists and DIY welders to artists and automobile enthusiaststo utilise welding to fabricate and maintain material for whatever purpose they need. The MIG process is easy to learn and can be used on a wide range of metals (e.g. stainless steel, magnesium, nickel, copper, and other alloys) and thicknesses. Some people have even said that MIG welding is as easy as using a glue gun.
Of course, MIG welders are not that simple. While the principles of MIG welding has not changed since it was developed in the 1940s, the metals we work with, the equipment used, and the technology surrounding the process have all advanced and will continue to do so for the foreseeable future. Progress has greatly simplified MIG welding, making it one of the most accessible welding processes, but there is still a lot to take in to perform MIG welding properly and safely.
Here is some of the safety considerations you need to make when performing MIG welding. While using a MIG welder is relatively simple compared to other welding processes, the act is still fraught with dangers that can harm the welder. Welding itself is dangerous, thats why it is important that you equip yourself with the knowledge required to keep yourself safe.
Bright lights
Photokeratitis, also known as arc eye, is a painful condition that is commonly associated with MIG welders. The light produced by the welding process is extremely bright, and the bright flash can burn the cornea if the welder directly looks at the arc, even for a short time. The eyes are a sensitive organ, and the corneas particularly so. A person with arc eye can expect painful sensation similar to having sand in the eyes.
To eliminate the risk of developing arc eye, it is absolutely essential that the welder wear a full face welding mask to protect against the bright light and harmful UV rays produced by the welding process. Auto-darkening welding masks are now available, which are more convenient as the welder does not have to pull the mask up every time he needs to work with metal.
You also need to protect nearby workers and passersby from the bright light generated by the welding arc. Put up a welding screen surrounding the welding area and place sufficient warning signs around it.
Metal vapours
Melting and welding metal and angle grinding results in the creation of metal particulates and dangerous fumes which can seriously harm the welder if inhaled. Some metal alloys like aluminum alloy and galvanised steel with zinc coating produce poisonous vapours when the MIG welding process is performed. Exposure to metal vapours can result in heavy metal poisoning which may lead to damage to the lungs, brain and kidneys and even permanent neurological damage.
While the full face welding mask will protect you from the arc light and UV rays, it does little to stop the metal vapours. It is important that you wear a vapour respiration with a charcoal filter when welding. MIG welding should be performed in a well-ventilated area. If not. a dedicated oxygen supply for the welder is essential when welding in an enclosed space.
UV rays and molten metal
The light produced by the MIG welding process emits a concentrated dose of ultraviolet ray and can cause severe sunburn on exposed skin. Regardless of heat or comfort, the welder must wear full covering of neck, arms and legs. Welding shirts, jackets and aprons are available for that purpose. Do not wear thin, combustible clothing.
Molten metal is a natural byproduct of welding. The welder should wear welding gloves or gauntlets to protect his wrists and hands from the globs of hot metal that will cause severe burns. Do not wear clothing made of synthetic fibers like rayon and polyester as they will melt upon contact with molten metal. Leather is a good material for protection against molten metal. Wear steel-toed leather work boots instead of rubber or synthetic material shoes. Synthetic fabrics often melt and the molten metal will go through the material like butter.
Grinding noise
Angle grinders, along with other workshop tools, produce copious amounts of noise that can permanently damage hearing. Welders should always wear adequate ear protection while using any tool, whether its a grinder or a hammer, to reduce or eliminate the noise that reaches the ears. It is also important to wear eye protection as sparks and metal particulates may be produced while angle grinding.
