PhoenixDuctClean

Diagnostics & problems

The Dust You Can See on Surfaces Is an LEV Warning

A film of dust on a ledge looks like a housekeeping problem. It is really an extraction problem wearing a disguise. If dust is settling where you can see it, it was airborne first, and the fine fraction you cannot see went furthest.

Visible
Coarse fraction
Respirable
Invisible
Breathing zone
First stop
500+
Silica deaths a year
No dry sweep
For silica
Capture
At source
settledFALLOUT
TR19 certificate Before & after photos Filters degreased Fully insured EHO accepted

The short answer

Visible dust is escaped dust, and the dangerous part is invisible

Dust settling on surfaces, beams and window ledges is not first and foremost a cleaning matter. It is proof that dust which should have been captured at source instead became airborne, drifted through the workspace, and fell out of the air where you now see it. What you can see is only the heavy, coarse fraction. The respirable particles that reach deep into the lungs are too fine to see and travelled further still.

The detail

What the settled layer is telling you

An extraction system that is working draws contaminant into the hood at the moment it is released, before it can enter the room. When you find a growing film of dust on ledges and horizontal surfaces away from the process, it means release is outrunning capture: the hood is mispositioned, undersized, damaged or starved of airflow, or a duct is leaking so the pull at the hood has dropped. The dust took a path through the general air, and therefore through people's breathing zones, on its way to the shelf.

The visible fraction is also the least hazardous part of the picture. Coarse dust is caught in the nose and upper airway; it is the respirable fraction, invisible in normal light, that penetrates to the gas-exchange region of the lung and drives diseases such as silicosis and chronic obstructive pulmonary disease. A dust lamp, which lights fine particles side-on against a dark background, will reveal clouds of airborne dust that the naked eye misses entirely, which is exactly why a visible layer should be read as the tip of a larger problem.

What it means for you

Why you cannot clean your way out of it

Sweeping the surface removes the evidence, not the cause, and it can make matters worse. Settled dust is easily re-entrained: foot traffic, a passing trolley, a door swing or, worst of all, a compressed air line lifts it straight back into the air people breathe. For respirable crystalline silica in particular, dry sweeping and blowing down with compressed air are not acceptable control, and the Health and Safety Executive estimates over 500 construction workers die each year from past silica exposure alone.

So a recurring dusty film is a prompt to look upstream at the extraction, not to reach for a brush. A thorough examination checks each hood's position and capture, traverses the ductwork for leaks and settled dust inside it, and measures airflow against the commissioned figures. It answers the real question the dust is asking: where is capture failing, and what does it take to restore it. Housekeeping still matters, but it is the last line, not the control.

Respirable
Invisible fraction
500+
Silica deaths a year
Re-entrained
By sweeping

The service behind the guide

An examination that traces dust back to the failing hood

We treat visible dust as a lead, not a nuisance. Our examination finds the hood or duct that let it escape, measures how far capture has fallen, and gives you the remedial actions to put it right.

Questions

Frequently asked questions

Is dust on surfaces a sign my LEV is failing?

Usually, yes. Dust settles on surfaces because it became airborne instead of being captured at source. A growing film away from the process points to a hood or duct that is no longer controlling the release.

Why is the visible dust not the main danger?

What you can see is the coarse fraction, largely caught in the nose and upper airway. The respirable fraction that reaches deep into the lung is too fine to see and travels furthest, so a visible layer signals a larger unseen problem.

Can I just clean it up more often?

Cleaning removes the evidence, not the cause, and settled dust is easily lifted back into the air by traffic, doors or compressed air. For silica, dry sweeping and compressed air are not acceptable control. The fix is upstream at the extraction.

How does a test find where the dust is escaping?

A thorough examination checks each hood's position and capture, looks inside the ductwork for leaks and settled dust, and measures airflow against the commissioned design, isolating where capture has fallen.

What diseases are linked to the dust I can't see?

Respirable dusts are linked to silicosis, chronic obstructive pulmonary disease and lung cancer, depending on the substance. The Health and Safety Executive estimates over 500 construction workers die each year from past silica exposure.

20+ Years of Experience

Phoenix Duct Clean · by the numbers

Kitchen canopies
degreased
4,287
Laundry ducts
cleaned
1,877
LEV systems
tested
1,658
Hours
on site
54,754

Find out where the dust is really coming from

Cleaning the surface treats the symptom. A thorough examination finds the hood or duct that let the dust escape in the first place. Call to book a test that gets to the cause.