Particulate fume is made up mainly of complex oxides and silicates of metals present in the welding consumable being used. Its composition will be directly related to the composition of the filler metal being used in processes where the filler is a solid metal.
Welding fume is an unavoidable by-product of welding. It consists of particulate fume, the part you can see and gaseous fume, which you cannot see, but can sometimes smell. All welding processes generate welding fume, the type and amount varying from process to process; MMA, MIG, FCAW and plasma cutting tend to produce most, while TIG, plasma welding, laser welding and Submerged Arc give very little under normal circumstances, although TIG can give high levels of gaseous fume.
What is Particulate Welding fume?
Particulate fume is made up of discrete, very small, solid particles, which range in size from 0.01 to 10 microns, but these particles are generally less than 0.5 microns in diameter. This means that most of the fume falls into the 'respirable' size range, meaning that particulate fume can be breathed in, reach the lungs, and stay there.