Welding is the process by which two metal parts are joined. This is accomplished by melting the parts at the point of contact and simultaneously forming a connection with molten metal from the part themselves, called the parent metal, or from filler material. The filler material used to join the metal parts is called the consumable. Welding rods, welding electrodes, and welding wire are commonly used consumables. The process of melting the parent metal and the consumable produces concentrated fumes and gases. The consumable is the major source of the fume.
Welding fumes contain a number of different elements, depending on the metals being welded and the consumable being used. Elements contained in welding fumes include fluorine, manganese, zinc, lead, arsenic, calcium, sulfur, chrome, and nickel.
Fumes are rarely visible, however, the elements released in the fumes are still present.
The following types of welding generate exposure to manganese fumes:
- Shielded metal arc welding or “stick”
- Gas metal arc or metal inert gas (MIG) welding or “short arc”
- Gas tungsten arc or tungsten inert gas (TIG) welding or “heliarc”
- Flux cored arc welding
- Thermal cutting
- Metal pouring
Other types of welding include the following:
- Plasma Arc Welding (PAC, PAW)
- Submerged Arc Welding (SAW)
- Carbon Arc Welding (CAW)
- Electro Slag Welding (ESW)
- Electro Gas Welding (EGW)
- Stand Welding
- Oxyacetylene Welding
- Beddon Plate Welding
- Oxygen Cutting
- Air Carbon Arc Cutting
Typically, welding rods (or electrodes) are the consumables that contain the highest levels of manganese and Shielded Metal Arc (“stick”) welding is the type of welding that tends to release the most manganese fumes. However, this does not rule out other welding consumables or types of welding as potential causative agents.
Performing any of these types of welding, or working in close proximity to these activities, for extended periods of time can expose the worker to manganese fumes.
Experts have determined that as little as six months of exposure to manganese fumes, assuming 8-10 hours of exposure per day, 5 days per week, can cause neurotoxicity.
The most notable neurological problems that can be caused by this process are Manganese Poisoning, or manganism and Parkinson’s Disease.