Fume extraction and environmental systems are designed to control welding fume exposure. Mechanical ventilation is an effective method of fume control for many welding processes. Because it captures fume near the arc or source of the fume, which is more efficient in most cases, local exhaust, also called "source extraction", is a very effective means to control welding fume. Source extraction of welding fumes can be provided by mobile or stationary, single or multi-station, exhaust and/or filtration equipment designed with adjustable fume extraction arms nozzles or guns, by fixed enclosures, booths or tables with extraction canopies also known as down-draft, or by back-draft or cross-draft tables/booths. Source extraction of weld fume falls into two categories: low vacuum/high volume or high vacuum/low volume.
Mobile or stationary, single or multi-station, large centralized exhaust and/or filtration equipment designed with adjustable fume extraction arms are usually low vacuum/high volume systems.
High vacuum/low volume fume extraction systems are designed for close proximity (2 to 4 inches) positioning. There are two methods of high vacuum extraction: welding guns with built-in extraction (fume extraction guns), or separate suction nozzles of various designs. High vacuum equipment ranges from small, portable, mobile units to stationary, single or multi-station, large centralized filtration systems