Air Quality Testing

Air‑O‑Cell Test (Air Sampling for Mold)

What it is:
An Air‑O‑Cell test is a type of indoor air quality test that collects airborne particles—such as mold spores, pollen, dust, and fibers—using a small cassette attached to a calibrated air pump. The collected sample is then analyzed under a microscope by a lab to identify and count the types of particles present.

When it’s recommended:

Suspected mold growth (musty odor, water damage, visible staining)
Unexplained respiratory symptoms (coughing, wheezing, allergies, asthma flare‑ups)
After water intrusion or flooding
During real estate inspections or indoor air quality assessments
To compare indoor vs. outdoor air quality

How the testing process works:

A technician places an Air‑O‑Cell cassette on a pump and draws a known volume of air (usually 5–15 minutes).
Airborne particles impact a sticky slide inside the cassette.
The cassette is sealed and sent to a laboratory.
A lab analyst examines the sample under a microscope to identify particle types and concentrations.

How to interpret the results:

Results are typically reported as spores per cubic meter (spores/m³).
Indoor levels should generally be similar to or lower than outdoor levels.
Elevated indoor counts, especially of specific types (e.g., Stachybotrys, Chaetomium, Penicillium/Aspergillus) may indicate active mold growth indoors.
A qualified inspector or environmental professional should interpret results, taking into account building conditions, sample locations, and occupant health concerns.

Radon

What it is:
Radon is a naturally occurring, invisible, odorless radioactive gas that forms from the breakdown of uranium in soil, rock, and groundwater. It can enter homes through cracks and openings in the foundation and build up to unsafe levels indoors.

How it is tested:

Short-term tests (2–90 days): Use charcoal canisters, liquid scintillation, or continuous monitors to get a quick snapshot.
Long-term tests (90+ days): Provide a more accurate annual average of radon levels.
Test kits are placed in the lowest livable area of the home, away from drafts, and either sent to a lab or read by a digital monitor.

What the results mean (EPA guidelines):
Radon is measured in picocuries per liter (pCi/L):

0 – 2.0 pCi/L: Low risk (no action typically needed)
2.0 – 3.9 pCi/L: Moderate level; consider mitigation
4.0 pCi/L or higher: Action level — mitigation is recommended

The EPA advises that no level of radon is completely risk-free, but higher concentrations significantly increase long-term lung cancer risk.

How radon is mitigated:
The most common method is a sub-slab depressurization system, which includes:

A pipe installed through the foundation slab or under a crawlspace barrier
A fan that pulls radon gas from beneath the slab or barrier
Venting the gas safely above the roofline