Laser Workshop Air Quality: What I Learned After 3.5 Years of Cutting Wood All Day
Last week I ran a laser training course for two guys from a sign company in Merseyside. Brilliant session — they arrived as complete beginners and left confident on LightBurn, materials and settings. But the conversation that stuck with me happened during a break, when we got onto safety and air quality.
It turned out neither of them had thought seriously about what was in their workshop air. Not through carelessness — just because nobody had ever told them they needed to. And I recognised that, because three and a half years ago, neither had I.
The problem you can't smell
When you cut or engrave wood with a CO2 laser, the heat doesn't just produce visible smoke. It also produces formaldehyde (HCHO) and other volatile organic compounds (TVOCs) — many of which are colourless, odourless, and genuinely harmful. Formaldehyde is a known carcinogen. TVOC exposure over time is linked to a range of respiratory and neurological effects.
For the first year or so I assumed that if I couldn't smell anything, the air was fine. I was wrong. The day I bought an air quality monitor and switched it on in my workshop during a cutting session was a revelation. The numbers were not healthy. The extraction I had set up wasn't enough. And I had been sitting in that air for months.
That started three years of trial and error that eventually got me to where I am now: a workshop where the monitor reads healthy during a full commercial cutting day. Here's how.
1. Extraction — and not just any fan
The fan that comes with an OMTech machine moves air. It doesn't move enough air, reliably enough, for a full commercial day of cutting. The upgrade that made the biggest difference was the AC Infinity CLOUDLINE S6 — a 150mm inline duct fan with a built-in speed controller. One of mine has run all day, every day for three and a half years. The only maintenance it has needed is an annual clean. It is, without question, the gold standard for this application.
The key numbers: 150mm diameter, variable speed, quiet, built to run continuously. If you're cutting commercially and using the stock fan, you're underextracting.
2. Ventilation — the obvious thing people miss
If you're pushing large volumes of air out of your workshop, that air has to come from somewhere. If it's coming back in through gaps near your extraction outlet — which happens more than you'd think, especially in smaller spaces — you're circulating contaminated air rather than replacing it.
Your clean air intake needs to be on the opposite side of the room from where the extracted air exits. Sounds obvious. It took me embarrassingly long to realise I'd got this wrong.
3. Sealing — every joint, every time
Dirty air under negative pressure is ingenious at finding its way back into your environment. Any unsealed joint in the duct run — a loose collar, a gap at the fan housing, a connection that isn't taped — will leak. And because the fan creates negative pressure on the inlet side, those leaks pull contaminated air back in rather than out.
Seal every joint with aluminium foil tape. Not gaffer tape, not electrical tape — foil tape designed for ductwork, which handles the heat and doesn't degrade. Check your connections regularly and reseal anything that looks compromised.
4. Measure — because you cannot trust your nose
This is the most important thing in this post. You need a monitor. Not because you'll use it every day forever, but because you need to know your setup is actually working — and you need to know immediately when something goes wrong.
I use the Temtop LKC1000S+ Air Quality Monitor. It measures PM2.5, PM10, formaldehyde (HCHO), TVOC, AQI, temperature and humidity simultaneously, and gives you a simple Healthy/Unhealthy reading on the display. When it says Healthy during a full cutting day, I know my setup is working. When the numbers creep up, I know something has changed — a seal has gone, the fan needs a clean, the intake is blocked — and I fix it before the air becomes a problem.
The photo above shows my workshop readings during a recent cutting session: HCHO 0.02 mg/m³, TVOC 0.11 mg/m³, status: Healthy. That's the goal. Three years of iteration to get there.
The ability to measure is what lets you refine your process. Without data, you're guessing. With a monitor, you know.
The conversation that prompted this post
The two guys from Merseyside left with their training and, I hope, a clear action plan on air quality. One of them said he'd been running his laser in a converted shipping container with no extraction whatsoever. That's an extreme case — but the underlying issue isn't unusual. Most laser operators I speak to have done some extraction, but very few have measured whether it's actually working.
If this post prompts you to buy a monitor before anything else, it's done its job. You might be surprised by what you find.
Related reading
For the full setup picture before your machine arrives — space, power, cooling and air assist as well as extraction — read the pre-delivery setup checklist. For everything about maintaining the machine once it's running, the workshop maintenance guide covers lenses, mirrors, lubrication and air assist. And if you want to learn all of this in a single hands-on session, our laser training course is available in person or by video call.
Disclosure: The AC Infinity and Temtop links in this post are Amazon affiliate links — we earn a small commission if you buy. Both are products we use ourselves in daily commercial production.