Nomad

Welding and laser welding generate ultrafine particulate that stays airborne and is small enough to be inhaled deep into the lungs. A fume extractor captures that particulate at the source, filters it, and returns clean air to the shop. Source capture is the key part. Pulling fume at the arc is far more effective than trying to filter a whole room after it has already dispersed.

That is what it was built for. Nomad is over 100 lbs lighter than typical units at 154 lbs, rolls over rough ground, and fits through a 30 inch doorway. It is the first portable unit with a full-size 10 ft capture arm, so you are not trading reach for portability. It handles laser, MIG, TIG, stick, and flux-core, which covers most of what a mobile crew runs into.

Yes. Every Filtrabox unit is designed for indoor use with no outdoor ventilation required. Air is captured at the source, filtered, and recirculated back into the workspace, which means no ducting through a wall or roof and no conditioned air being pumped outside. One thing to confirm for your process: recirculation depends on the filtration matching what you produce. Particulate is handled by the standard configuration, and gases or VOCs require the carbon cartridge.

Pre-filters and HEPA filters capture particles. They do not remove gas-phase contaminants. If your process produces gases, odors, or VOCs, you need the activated carbon chemical cartridge, which adsorbs them. Most welding and laser welding is a particulate problem, so the standard configuration is usually the right one. Processes involving coatings, plastics, or chemicals are where carbon matters.

They do different jobs and they are not interchangeable. The pre-filter takes the coarse and fine particulate first, so the HEPA only has to deal with what gets past it. The HEPA then captures the ultrafine submicron material at 99.999% efficiency on 0.3 micron particles. Because the pre-filter absorbs most of the loading, it is the element you replace more often, and it is the cheaper of the two. That is by design.

The steel mesh spark arrestor is washable and reusable, so that one gets cleaned rather than replaced. The pre-filter and HEPA cannot be cleaned. Attempting to blow out or wash filter media damages the fibers and destroys the efficiency rating, which defeats the purpose of having a HEPA in the first place. Those are replacement items.

There is no fixed interval, because filter life depends on what you weld, how much, and at what duty cycle. A shop running production all day loads filters far faster than one welding a few hours a week, and heavier particulate processes load them faster still. Rather than guess at a calendar, watch the pressure gauge. Rising pressure across the filter means it is loading up and approaching replacement. The pre-filter is designed to be the element you change most often, which protects the more expensive HEPA behind it.

All three move 1154 to 1200 CFM, so airflow will not decide it. How and where you work will. Nomad is the one that leaves the building, at 154 lbs with a 30 inch doorway clearance for field service and mobile crews. Weld-RX is the shop workhorse, on casters so it repositions around the floor, with the largest filter area in the line at 22 m2 for high duty cycle work. Vert-X mounts on the wall and gives up mobility entirely in exchange for zero floor space. Contact the factory if you are unsure, since duty cycle and application matter more than the headline airflow number.