Small welding shops have a special issue with air quality. They’re cramped, they’re budgeted, and they have enough variance in work to make for a “one-size-fits-all” approach unrealistic. Yet when it comes to fume extraction, there is no longer a choice; it needs to be done in the first place.
With health inspections, insurance considerations and the fact that breathing in metal for an entire workday will take its toll on one’s health regardless at some point, it’s not an optional consideration.
Unfortunately, many small shop owners think about their ventilation system as an afterthought. They’ll buy the best welder that they can afford, get their metal inventory set up properly, set the right lighting, and then determine down the line that they have a smoke issue.
But by then it’s too late and they’re trying to implement a solution into a preexisting area not designed for it. This means it’s more expensive and less effective than if it were merely designed from the get-go.
Recognizing What You’re Actually Working With
Welding fume is not a collection of annoying smoke that permeates your shop; it’s an amalgamation of metals that compound based upon what you’re welding and how you’re welding it. Someone who’s MIG welding mild steel isn’t creating the same fume as someone TIG welding stainless or stick welding galvanized.
These particles are small enough to stay suspended in air for up to hours at a time. Thus, if there’s no extraction to remove them immediately, they settle on any surface in the shop and are breathing back in consistently throughout the day. Just because you can’t see the haze, it doesn’t mean it’s not there. That’s where the long-term health issues come from – not from one awful day but many days of small neglect.
Additionally, different welding processes create fume in different volumes; stick welding creates more fume than MIG, for example, and flux-cored wire creates more than solid wire. A small shop that accepts various jobs needs to ensure that its extraction system can accommodate what is presumably the worst-case scenario for the amount of fume created – not just a light job here or there.
Assessing Your Own Needs
Many small shops either order systems that are too powerful for their needs or not powerful enough for their needs based on improper measurements. To establish how much extraction is needed, one must figure out their air volume and how many welders are functioning at the same time. A 2,000 square foot shop with two welders at once has different needs than a 1,200 square foot space with one welder now and then.
Air changes per hour are more critical than one thinks. For a welding atmosphere, this usually comes down to 20-30 per hour as a baseline. This sounds complicated, but it basically means that your volume divided by your extraction pounds means that this is how much air you’re working with. If your calculations don’t come out, you will always be fighting an uphill battle against fume accumulation.
The location of your welding stations relative to your extraction points makes a huge difference too. Fumes rise and spread, so trying to pull them from across the room after they’ve dispersed throughout your space requires way more power than capturing them right at the source.
Professional welding supply specialists stock complete extraction systems, and you can find here options designed specifically for different shop sizes and welding applications that take these variables into account.
Mobile or Fixed Systems in Small Spaces
This is an area where small shops have an advantage over larger spaces – flexibility. Mobile fume extractors can maneuver from station to station, accommodating various projects as they come without having to install ductwork throughout the entire shop for a permanent solution.
For shops who do various work or anticipate a layout change from time to time, mobile units make sense. However, portable fume extractors require someone to actually put them in the right position and turn them on, which sounds silly but oftentimes doesn’t happen because they get stuck in the corner somewhere because they’re in the way or the person thinks it’s too much work to set something up for a quick job.
However, these quick jobs add up because they’re given without extraction equipment and lead to enormous fume exposure.
Fixed units are permanent with flexible arms or hoods for dedicated welding stations. Once it’s set up, it’s ready to go at all times. While it’s more involved upfront, and thus more expensive, in installation, for shops that have specific stations where they always weld, it’s less time-consuming and ensures air quality every time.
Some shops split the difference, a fixed system for their primary welding station and a more mobile unit for other occasional work throughout the shop. This covers most bases without needing extraction ports everywhere.
Power Considerations and Practical Limitations
One of the most surprising issues that catch people off-guard is power requirements of an extraction system. A fume extractor is not the same thing as a shop fan; it requires motors and large CC required to suck out contaminated air through its filters and send air outside again. This requires power multiple times over.
Small shops often find that their electrical service does not have enough amperage available once their welding units and other machines are plugged in to accommodate a high powered fume extraction unit as well. This is not something that should be assessed post-purchase; this should be determined during preplanning.
Noise is another issue that spec sheets fail to highlight adequately enough. Operating an extraction system all day every day is background noise, and when working in a small shop with one or two other people (or themselves), it impacts operation more than it would impact a larger space.
Filter Maintenance Truths
All extraction units have filters, and filters need to be changed periodically. Depending upon how much welding one is doing and which materials are welded, filters might need changing every few months minimum for busy small shops.
The first consideration is the cost of filters. Budget systems with cheap filters will be enticing – but if they need to be replaced twice as often as high-end systems with durable filters that ensure better filtration efficiency and longer times between service people should tally which factors cost less long-term (although high-end products are more expensive at their onset).
The reality check comes from performance degradation; if filters aren’t changed timely, systems will not only perform inefficiently but also damage motors that work too hard because additional resistance has taken place. While many systems have filter monitors, those metrics only help if someone actually pays attention – and has replacement filters on hand readily available.
Making It Work in Limited Space
Small shops rarely have spare square footage lying around unused without purpose. Thus extraction systems take up space with metal stock, multiple welders, grinders and everything else necessary on hand at all times. Wall-mounted systems and ceiling-mounted hoods save on floor space but require solid mounts and appropriate placement relative to working areas.
Ductwork also has the potential to exist above shop-level, yet in small areas this can dictate how well materials move around corners and what size pieces can be comfortably handled; advance planning on paper before installation saves from aggravating moments down the line.
The Bottom Line for Quality Shop Air
Achieving effective fume extraction within a small welding shop will ultimately depend on honest assessments of working capabilities versus realistic installation parameters along with cost analysis over time versus immediate concern. The cheapest solution that’s effective on paper isn’t necessarily the best if it’s inconvenient enough never to be actively used while the most extensive solution available can also be overkill if service cannot support wattage levels required due to each electrical outlet used by equipment.
Instead begin by assessing one’ s working volume, top three processes utilized most and how one’s layout actually exists on a day-to-day basis to match extraction capacity needs based on one’s worst-case scenario, not average workload powers applied everywhere at any given time, and relative mechanical efficiency.
Additionally, account for onsite time for replacement and maintenance costs associated with every option before comparing models, because most importantly it’s critical to set it up so using it becomes the easiest path taken, because a running system is far better than one that’s merely waiting for something right to happen.
