In TIG and MIG welding, electricity is drawn from a power source through an electrode down to a work piece. The intense heat from the live current can create a weld. Electrodes are engineered to drip down onto a work piece or not. Electrodes that melt are referred to as consumable electrodes; electrodes that do not melt are non-consumable. The MIG method of welding employs consumable electrodes; the TIG method utilizes non-consumable electrodes. The American Welding Society's identification system makes it easier for consumers to purchase the right electrode. The first two or three digits in an electrode's identification number indicate tensile strength. The electrode's next-to-last digit indicates the proper direction in which to hold an electrode. An electrode's last digit indicates the outer coating, if any, that has been applied to the electrode. Coatings can greatly increase welding efficiency in many applications.
Shielding gases also greatly increase welding efficiency. They are used to surround and stabilize the arc of electricity drawn down to a work piece through an electrode. Argon is the most widely used gas for welding shielding gas applications. Depending on the application, adding other chemicals to the argon such as oxygen, carbon dioxide or helium can also have a positive impact on performance. Argon and combination shielding gases are easily available to consumers at many home-improvement stores and welding specialty shops.
Welding curtains promote a safe work environment. Welding curtains are designed to protect bystanders from injury or exposure to the fumes and debris that may be produced while welding. OSHA (Occupational Safety and Health Administration) dictates welding curtain standards in America. Welding curtains must be constructed with an outer layer of non-combustible material. These curtains are often produced with a layer of zinc oxide for low reflectivity to prevent flash burns. To allow for floor-level air circulation, these curtains should be hung a few inches from the ground.
Welding requires additional safety equipment. A welder should never attempt to make a weld without wearing a specially designed, welding mask/helmet. The electricity from an electrode can reach a couple thousand degrees Fahrenheit. Gloves engineered to withstand such extreme temperatures should be worn while welding. Exhaust fans are often used to properly vent areas where welding takes place.