Welding is one of the most demanding and hazardous metalworking processes for a fabricator. The heat, the sparks, the spatter, the uncomfortable positions – it all makes for one long day. Welding fumes, however, might be the biggest hazard to which the welder is exposed.
The understanding of welding fumes has changed significantly over the years with more current knowledge about metals, gases and carcinogens leading to new and revised standards. Standards related to manganese, a metal present in most welding fumes, have evolved over the years. More recently, hexavalent chromium was deemed a carcinogen associated with welding in chromium metal. In 2017, all types of welding fumes were classified as a Group 1 carcinogen by the International Agency for Research on Cancer.
“For facilities that perform welding, the No. 1 priority is to watch out for welder safety and try to eliminate as many potential risks as possible,” says David Littleton, environmental safety coordinator, Fronius USA. “Many hazardous particles and gases are released in the welding process that can cause respiratory issues, neurological damage and cancer. There is also an OSHA mandate that requires employers to provide ventilation systems to keep chemical exposures below certain limits.”
Welding fumes consist of fine, solid particles of metal and other substances. Without adequate protection from fumes, typical welder illnesses include headaches and metal fume fever and more serious conditions, such as respiratory and neurological diseases.
Fume formation
All types of arc welding processes produce fumes that affect the welders and the rest of the people in the shop. The degree of harmfulness of the released fumes depends on the welding process, base material, filler metals and protective shielding gas. Extra caution should be used when welding stainless steel and galvanized steel, for instance. Welding process fume production includes:
- High welding fume and spatter formation: The varied application areas and different process variants of MIG welding increase the danger of fumes, spatter, etc. It should be noted that modified MIG welding process variants PMC (Pulse Multi Control), LSC (Low Spatter Control) and CMT (Cold Metal Transfer) offer significantly lower fume and spatter formation.
- High welding fume and spatter formation: For stick welding, electrical current and heat, UV radiation and, above all, increased fume formation are everyday risks. The type of hazardous materials in the fumes is crucially dependent on the electrode material and its coating.
- Low welding fume formation, spatter-free: A relatively small amount of visible fumes is produced from TIG welding. This low fume formation, in conjunction with the often highly reflective surfaces of the base material for TIG (typically, stainless steel or aluminum), results in an increased spread of the UV rays. This increases ozone
formation, often at some distance from the welding point. - Low welding fume formation and UV exposure: The lowest health and safety risks come from automated welding, often found in welding cells. The protective enclosure with automatic glare protection and integrated extraction provides optimal protection against fumes, spatter and UV radiation for anyone standing near the cell.
Movable extraction
While most welding hazards can be addressed with proper PPE, such as helmets and clothing, protection against welding fumes includes equipment such as centralized air filtration and stationary and mobile fume extraction devices. This is in addition to PPE such as powered air purifying respirators.
Mobile extraction devices, such as the ones available from Fronius, combined with fume extraction arms or torches, are used to capture welding fumes at the source, providing protection from fumes in all environments. The Fronius devices’ high mobility and 360-degree usage radius make them particularly flexible, which is ideal for changing workplaces.
With its high filter quality, the Exento HighVac mobile high-vacuum extraction system removes more than 99.9 percent of captured fume particles for significantly lower fume exposure. In combination with the Exento fume extraction torch, the high-vacuum system captures fumes directly at the source.
It is equipped with an extra-large, vertically mounted filter cartridge, ensuring effective cleaning. With a floor area of approximately 60 cm by 60 cm, the device takes up minimal space. The compact design does not take away from performance: Depending on the model, extraction capacity can reach up to 170 m3 per hour. Cleaning is particularly effective thanks to the vertically mounted filter cartridges.
Other benefits include high extraction capacity thanks to side channel blowers; intuitive, single-button operation, even while wearing gloves; automatic air volume flow control; extraction capacity monitoring; and infinitely variable pre-selection of the extraction capacity for use with a variety of fume extraction torches.
The Exento LowVac mobile low-vacuum extraction system protects welders from fumes in an effective manner and is cost-effective thanks to its long service life. It has a disposable filter with a large filter area at 25 m2, which is replaced with a clean one when saturated. Whether MIG, TIG or stick welding, the device plays to its strengths during all common welding processes thanks to the flexible extraction arm with flow optimized extraction hood. The low-vacuum system is particularly suited for applications where fume extraction torches cannot be used, such as stick welding.
Benefits include less need to reposition the extraction arm thanks to flow-optimized design of the extraction hood, increased safety due to filter monitoring and contamination-free filter replacement, and 360-degree rotatable extraction hoods with throttle valve.
Torch systems
Fume extraction torches eliminate welding fumes at the source. Ergonomics are particularly important for fume extraction torches as they are typically heavier and larger compared to conventional welding torches. Solutions need to offer the necessary safety with required working comfort at the same time. Having lightweight torch systems and cables, ergonomic and non-slip torch handles, fast retooling options and flexible operation are features that help with the health, safety and performance of the welder.
Exento fume extraction torches feature five power categories: 3X air-cooled and 2X water-cooled; LED light, 1.3-m long protective leather tube directly on the handle for protection against high temperatures and spatter, and quick testing of the extraction capacity directly at the extraction nozzle. Extraction capacity can be controlled directly on the handle.
It is clear that welders who work with a high level of protection and comfort will also achieve high-quality, consistent welding. Welding is well-known to be inherently risky, but with comprehensive health and safety measures along with well-designed equipment in place, welders can build rewarding careers in a high-demand field.
“Stats show that a healthy employee is typically a happy employee,” Littleton says. “Happy employees tend to take fewer sick days and have higher morale, which, in turn, leads to increased productivity. Owners want to protect their employees’ continued health and safety and ensure that they go home to their families in the same good health they came to work.”
