Mold can pose serious risks to both human health and the structural integrity of a property. It often reveals itself through a persistent musty odor, which typically signals excess moisture—whether from leaks, condensation, or inadequate ventilation. These damp conditions allow mold to grow on walls, ceilings, and other porous materials. Over time, mold can degrade these building components, compromising structural integrity and leading to costly damage.
⬡ Pictured above is suspected Serpula lacrymans – a wood destroying fungus – actively degrading this structural component.
Photo taken by Axxonlab in Montreal (2025)
As it grows, mold releases spores into the air. These allergenic particles and can trigger respiratory symptoms, asthma flare-ups, and other immune responses, especially in sensitive individuals. In some cases, mold also produces mycotoxins—toxic secondary metabolites that certain fungal species generate under specific environmental conditions. Mycotoxins are not always airborne in the same way as spores, but they can be present on surfaces and in dust, where they may linger long after the mold itself is removed. Depending on the type, mycotoxins can affect the nervous system, disrupt hormone function, or even cause cellular damage.
Addressing mold is not just about removing stains or odors—it means identifying the source of moisture, understanding the potential health implications, and protecting the long-term safety of the indoor environment.
Before explaining how mold is tested, it’s important to know when you should consider testing. There are many valid reasons to hire specialists to assess your indoor air quality and test for mold.
One of the most common reasons is water damage. Since mold requires moisture to grow, any incident involving water—such as basement flooding, leaking pipes, or overflows from toilets, sinks, or bathtubs—is a strong indicator for mold testing. Even condensation problems, often caused by insulation issues, can warrant a mold assessment.
Because mold can grow undetected behind walls or under flooring, unexplained respiratory symptoms are also a good reason to get your home assessed. Ultimately, there is no wrong time to book a mold assessment. Whether it’s for peace of mind or part of a property transaction, mold testing is always a valid and proactive step.
Our mold assessments begin with the arrival of our lab-approved sampling technicians on-site at the requested property. After a thorough briefing with the client, we document all relevant background information—such as past water damage, visible issues, reasons for assessment, and any health concerns.
The inspection begins, much like any first impression, with a visual assessment. The technician examines overall cleanliness, levels of dust, discolorations, visible mold growth, water stains, and any musty or foul odors. Clients often guide the technician to areas of concern.
Air testing is one of the primary tools used to determine whether mold is affecting indoor air quality.
We use a calibrated air pump to draw indoor air through a device called a spore trap. This device captures spores and airborne debris on a glass slide coated with a gel-like surface. The trap is then returned to our laboratory for microscopic analysis. Spores are identified, counted, and converted into an air concentration value based on the known volume of air sampled.
We also collect an outdoor air sample to serve as a reference. Comparing indoor and outdoor samples helps us determine whether high spore counts originate from inside or outside the property.
Surface sampling is another core method used in mold assessments. If visible mold growth or unknown discoloration is observed, the specialist collects samples using tape-lifts (pictured above) or swabs:
These samples are then analyzed in the lab. When combined with air test results, we can confirm whether visible mold growth is contributing to airborne spore levels by identifying the same species in both samples.
While air samples are being collected during the mold assessment, our technicians also perform real-time environmental diagnostics to better understand the conditions within each space. These measurements provide critical context for our laboratory analysis, helping to identify factors that may support or inhibit mold growth. In each room sampled, we document the ambient temperature, relative humidity, and carbon dioxide (CO₂) levels. Elevated humidity or poor ventilation are key contributors to fungal proliferation, and monitoring these variables helps us assess whether the environment is conducive to hidden or active mold growth.
Since mold is often a symptom of an underlying moisture issue, we also utilize infrared cameras to detect thermal anomalies within walls, floors, and ceilings. These temperature differences may indicate hidden leaks, cold spots, or insulation deficiencies that lead to condensation buildup. If a potential moisture anomaly is identified through thermal imaging, our technicians will validate it using specialized moisture meters. These instruments—whether pin-type or non-invasive—allow us to measure moisture levels within materials at varying depths and confirm whether the building material (e.g., drywall, wood, etc.) is retaining water.
In certain scenarios, we may also measure VOCs (volatile organic compounds) and particulate matter (PM) concentrations. Some mold species emit microbial VOCs (mVOCs), which are often responsible for the characteristic musty odor associated with contaminated environments. Monitoring VOC and PM2.5 levels can provide further insight into the indoor air quality, ventilation efficacy and the possible presence of biological or chemical contaminants.
Once the comprehensive mold assessment is complete, we prepare a detailed, photographic report that includes:
Our experts interpret the findings to determine whether remediation is required and provide valuable tips for preventing future mold growth.
If you’ve ever asked yourself, “how do you test for mold?” — the answer is more than just taking a sample. It’s about understanding the environment, interpreting invisible clues, and delivering clear, science-backed answers. At Axxonlab, we combine real-time diagnostics, precision sampling, and expert analysis to give you a complete picture of what’s in your air and on your surfaces.
Whether you’re reacting to health concerns or planning ahead, we’re here to turn uncertainty into insight — and concern into confidence.
Yes. Our air tests can detect hidden mold—if it is sporulating and affecting surrounding air quality. Spore trap cassettes collect microscopic airborne spores, enabling us to detect and identify hidden mold problems.
With Axxonlab, results are typically available within 24–48 hours, depending on the selected service package. Holidays and weekends may affect turnaround time.
We use calibrated air pumps to collect 75L of indoor air per sample using spore trap cassettes. Spores are then microscopically identified and counted, and results are reported in spores per cubic meter of air. This ensures scientifically valid, highly accurate readings.
