Why Sampling Mold Is Important

As one of the few mold inspection companies specializing in cases involving hypersensitive individuals, we get countless calls, messages, and emails inquiring about advice on whether a person should stay or leave their residence. People will describe a situation and seek specific answers about what is safest for them. 

Every time our answer is: We can only answer with data from sampling to understand the health of the home or office. From there, it is essential to share that data with your doctor to make the best decision for them and their family.

So, why is sampling so important?! Let’s look at a few examples to illustrate a few different scenarios. 

Case Studies

A mold sampling in a petri dish

Scenario #1 –  Angela and Victor bought a home that was rebuilt from the foundation up. The home in Florida is stucco with a wood frame. The house has all brand-new materials. However, a few months after moving in, Angela started getting fatigued, having heart palpitations, nightmares, and a ringworm rash, among other symptoms. Victor eventually had some depression, anxiety, and paranoia that he did not have before living in this house. There was a minor mold problem in their master bedroom that they had remediated immediately. Other than this, there is no visible evidence of mold or water damage besides a mild odor that is apparent when you first walk into the home. 

Scenario #2 – Tyler just moved into a new condo. One month after moving in, there was a leak in the ceiling of his master bathroom. He had it remediated immediately, all materials have been replaced, including insulation, and he lives in a dry climate. He has a few symptoms but has mostly been feeling good; it’s hard for him to tell if it’s his home or another variable making him not feel his best. 

What does the testing show for both of these places? 

Scenario #1 –  Angela and Victor had an ERMI of 29! In sampling their HVAC, stachybotrys and chaetomium were present in their unit. Sampling from inside the walls also showed aspergillus. We took various samples from every room, and none came back clean, except on spore trap analysis (More about that in our previous article, Why Air Testing is Not Enough). Angela and Victor have a whole house mold problem, and their residence is unsafe to live in, even for a healthy person! 

Scenario #2 –  In Tyler’s location, an ERMI was collected with a result of 5.3 and a HERTSMI-2 score of 2. His HVAC was clean. There were not that many toxic molds, and it appeared it just needed further remediation to make it safe for him to live. His issue seems localized, and he does not have a whole-house problem. 

What Can Sampling Tell Us 

Our work at Certified Mold Assessments is scientific. To give our clients and their doctors an accurate understanding of what they are exposed to, we must use third-party labs to analyze the samples we collect during the inspection process. Sampling gives us data to set the road map to return your home to a healthy condition by helping you prioritize remediation decisions and costs, if necessary. 

Some of the things testing can tell us:  

  • Where is there active water damage? 
  • Where are the sources?
  • Is this a whole house issue, or is the problem localized to one area? 
  • Does the HVAC need to be replaced or remediated?
  • Which species of mold are present? The resident may be more sensitive to particular species, which can be helpful information for their doctor. 
  • Are mycotoxins or endotoxins present? 
  • It gives you insight into how the dwelling’s contents need to be approached.

Types of Sampling We Use 

Spore Trap Analysis (Air Testing)

SURFACE TESTING (Source Testing)- Surface samples are typically taken from areas of visible suspect growth. They can collect them via sterile swabs, tape lift, or by taking a piece of suspect material. These samples are essential because they may reveal reservoirs of mold that have not yet become airborne.    

ERMI (Environmental Relative Moldiness Index) –  ERMI is an objective, standardized DNA-based testing method that will identify and quantify molds. This testing analyzes the moldiness index in dust that has settled in the home. In this case, we are not relying on the fact that the mold spores will be airborne when testing. This allows heavier molds a better chance of showing up on testing. The species of mold are split into two groups and given different weights regarding how toxic they are. A score is then given on the overall mold toxicity score. This score can be instrumental when comparing homes and deciding whether a hypersensitive individual should live in the home or vacate. 

HERTSMI-2 (Health Effects Roster of Type-Specific Formers of Mycotoxins and Inflammagens) – That’s a mouthful! The HERTSMI-2 is a more specific scoring system that identifies the most toxic molds. This scoring system is extrapolated from the ERMI test. In this scoring system, molds included are known to produce mycotoxins, which are among the primary triggers for mold sickness in water-damaged buildings. 

Mycotoxin testing – There is no way for an inspector or technician to know if a mold is producing mycotoxins or not unless we test for actual mycotoxins present. Knowing if mycotoxins are present and at what levels can be very useful in determining whether a home is safe to live in (or not). 

Endotoxin Testing – Endotoxins are derived from the cell walls of Gram-Negative bacteria (GNB). Gram-negative bacteria are found almost anywhere in nature. It has recently been discovered that endotoxins are a major contributing factor to cases of biotoxin illness. 


In short, it is only possible to weigh the pros and cons of remediation versus moving out if you have enough data. Sampling and analysis by a third-party lab help us determine if the HVAC is compromised, if there is a whole-house issue, what potentially toxic substances are present that could cause illness, and at what severity level. 

Find Us on Social 

For more tips, or if you are interested in learning how to face life’s challenges with mold sickness, please follow us on Instagram and Facebook. If you have any questions or comments, feel free to leave them in the comments below or on our social media. 

And, of course, please book your inspection today!  While we are always sorry to hear of anyone with a mold issue, we look forward to sharing our experience, insight, and resources with you!