Welding Digest

Every industrial manufacturing facility has unique processes. There’s no one-size-fits-all solution for managing welding fumes. This Q&A can help facility managers consider the most effective fume extraction strategy.

Using a fan, opening a window, or welding outside can greatly reduce employee exposure levels but shouldn’t be the total solution. The American Conference of Governmental Industrial Hygienists recommends using fume extractors to actively and consistently capture fumes near sources and before contaminants disperse throughout a facility.

What Are My Dust and Fume Hazards?

Materials used, operational practices, and facility layout lead to welding fume hazards. Knowing the composition of the materials you’re producing will allow you to identify them and the performance expectations for a fume extraction system. 

Keep in mind that OSHA, the EPA, the NFPA, and other agencies may impact your strategy. Understand which codes and standards apply to your facility to ensure you make proactive design decisions that make sense for your application.

How Much Welding Fume Does Your Facility Generate?

If you operate 24/7 or weld for eight consecutive hours during a normal workday, you’ll likely produce a higher level of welding fume particulate and will want to consider fume extractors that run continuously, feature self-cleaning mechanisms, and use long-lasting filters to minimize maintenance downtime. Robotic welding will also produce a large amount of welding fumes with the same requirements.

On the other hand, if you mostly do manual welding and use welding stations intermittently, the ideal option may be a small, portable fume extractor. This equipment can be turned on and off depending on your shop’s demand.

What Method of Extraction Will Work Best?

The welding fumes collection strategy you select will depend not only on concentration and volume but also on the layout of your facility. It’s always preferable to remove fumes close to the source with each welding station having its own collection hood, extraction arm, or a work bench to capture fumes specifically generated by that operation.

However, factors such as overhead cranes, limited floor space, or cramped ductwork may compromise your ability to implement a source extraction method. In this case, an ambient welding fumes solution may be appropriate. Ambient solutions do not utilize close capture equipment at the welding site. Rather, an ambient collector draws in fumes from the entire area.

If you frequently rearrange your plant’s layout, an ambient extraction system, unlike a source extraction system, will give you the flexibility to reconfigure. 

Where Should Your Equipment be Located?

If you select source collection, you’ll need to decide where to locate the equipment in relation to the welding stations. Facilities with spread-out workstations find point-of-use layouts, where one collector is connected to one welding operation or station, convenient. Since each welding point has its own extractor, it’s smart to select and place an extractor with a small footprint directly adjacent or close to each workstation. 

In other shops, it might work best to use a centralized strategy. In these installations, one collector serves multiple workstations, and the stations connect to the extractor through a duct network. A shop typically locates a centralized collector some distance away from the welding points and may be a good option if floor space is limited where your welding occurs.

What Type of Filtration Equipment Is Most Appropriate?

Once you’ve determined your welding fume hazards, process needs, facility limitations, and extraction goals, you’re ready to select the fume extractor itself. This equipment draws in contaminated air, filters out particulates, and exhausts filtered air outdoors or possibly back indoors. Particles that settle in the extractor are collected in waste containers. 

There are two types of extractors, which are named for the filter style inside the equipment: cartridge or filter-pack. The filter captures the fume particulates. Both filter technologies work well; the one you choose may depend on the location of equipment and whether you select a point-of-use or centralized collector arrangement.

Cartridge systems come in a wide variety of designs and sizes, are easy to change, and provide maximum particle-holding capacity in a compact footprint. 

Filter-pack systems work well as point-of-use extractors or are integrated by the manufacturer to work with the welding equipment. 

Most fume collectors manufactured by Donaldson Co. Inc., Minneapolis, Minn. come with a pulse-jet cleaning function in which compressed air pulses the dust off the filters during operation, helping support long filter life. This function requires a compressed air source.

Use filters that are designed for sub-micron welding fumes. The media traps dust on the surface, creating a dust cake that pulses off easily and supports longer filter life.

What Are Other Best Practices?

Involve your welders in your system design. Capture devices, such as extraction arms, should be maneuverable and long enough for workers to adjust as they move around parts. Getting your welders’ input upfront will help develop a system they are more inclined to use. 

Ask a fume extraction professional for assistance. With many variables in the mix, it pays to work with someone knowledgeable who can analyze your operation and help design the ideal solution. 

In addition to welding fume equipment, invest in high-quality PPE for your team. Helmets, shields, gloves, and masks help protect against burns, sparks, spatter, bright light, loud sounds, and other exposures while welding. Industry professionals recommend using PPE like powered air purifying respirators (PAPR) in addition to a source or ambient welding fume strategy.

What Are the Most Important Factors for Budget Considerations?

Ultimately, a welding fume extraction system should meet your primary performance objectives and fit within your budget. Understanding what level of collection is needed to meet those objectives will help you decide what technology and equipment strategy are most cost-efficient and effective. Involve your employees in the welding fume collection discussions in order to find a strategy that will be used and effective at meeting performance goals. 

This article was written by Chrissy Klocker (applications engineering manager, Donaldson Co. Inc., Minneapolis, Minn.) for the American Welding Society.