How mold air testing works
We draw a measured amount of air through a sealed spore trap cassette (Air-O-Cell) in each room of concern, and take the same kind of sample outdoors as a control. A third-party laboratory counts and identifies the spores in each sample, and we explain the results in your report.
Air testing is usually part of a mold inspection, so the results come with the visual findings, moisture readings and thermal images that explain them.
Reading the results
There are no official limits for mold spores in indoor air, so results are judged by comparison. The outdoor sample shows what's normal in the air that day.
- Indoor levels similar to or lower than outdoors, with the same kinds of spores, usually point to no significant indoor source.
- Higher indoor levels, or kinds of mold that are rare outdoors, suggest something is growing inside, and the report says where to look.
The full lab report is attached, so anyone can check the numbers.
When air testing is worth it
- You smell mold but can't see it
- You need evidence for a landlord, buyer, seller or insurer
- You want to confirm a cleanup worked
- Someone in the home is sensitive to mold and you want to know what's in the air (alongside advice from their doctor)
If mold is clearly visible, testing often isn't needed to know it should be removed, and we'll tell you that rather than sell you samples. The EPA says the same.
What air testing can't tell you
- It's a snapshot of the air at the time of the visit. Spore levels change with weather, activity and ventilation.
- It doesn't diagnose health problems. For health questions, please talk to a medical professional.
- It's for mold. Radon, lead, asbestos and other pollutants need different tests.
Sources
Rules change. This page explains them in plain English and isn't legal advice.