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Microscope

Mold Testing
Air Quality Assessments
for Your Home

Reliable Home Inspection Service has over 16 years of experience in mold testing, making us a top choice for ensuring your peace of mind. Our co-owner and certified mold inspector John Kerrigan, is passionate about air quality and certified by the Indoor Air Quality Association.

 

We use reliable technology and send our samples to one of the best labs in the country, Pro-Lab, where every report is reviewed by a doctor of microbiology.

  • When moving. Especially if the home has a history of mold or water damage.

  • If you see signs of mold or smell something strange. Especially if you smell something strange, but can’t see anything.

  • If you’ve noticed water damage.

  • If you have mold sensitivities or allergies

  •  It's important to be aware of any signs of mold or water damage, such as visible mold or a strange smell. If you have noticed any water damage or have mold sensitivities or allergies, it's especially important to take precautions.

What are the effects of mold in my home?

  • Per the CDC, "Other recent studies have suggested a potential link of early mold exposure to development of asthma in some children, particularly among children who may be genetically susceptible to asthma development, and that selected interventions that improve housing conditions can reduce morbidity from asthma and respiratory allergies."

  • Per a recent study by the National Institute of Health, " Inhalation is considered the primary way that people are exposed to mold. Mold spores and fragments can become airborne and get into the air we breathe. People may also be exposed to mold through the skin. Workers should be properly protected with safety equipment when remediating, or cleaning up mold after a disaster. In some cases, people may be exposed to mold through their diet. Climate change is a concern for mold spread because conditions inside buildings are influenced by the environment outside them. Building deterioration may result from extreme weather events, increasing the likelihood of mold growth. Under climate change, allergenic mold levels may rise through increased indoor dampness and warmer temperatures."

Why Should you get a Mold Air Quality Test for your Home?

Should I be Concerned About Mold in My Home Yes. If indoor mold is extensive, those in you

Everyone is exposed to some amount of mold on a daily basis, most without any apparent reaction. Generally, mold spores can cause problems when they are present in large numbers and a person inhales large quantities of them. This occurs primarily when there is active mold growth. For some people, a small exposure to mold spores can trigger an asthma attack or lead to other health problems. For others, symptoms may only occur when exposure levels are much higher.

 

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The health effects of mold can vary. The production of allergens or irritants can cause mild allergic reactions and asthma attacks. The production of potentially toxic mycotoxins can cause more severe reactions and in rare cases death. There are possible links between mold and the development of asthma in young children.

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You should consider mold testing before buying a home. Mold remediation can cost thousands of dollars, with some homes costing as much as $10,000  to remediate. A test can help you avoid any future unforeseen remediation costs. The CDC found that 47% of US homes have mold problems, so a mold test is a no-brainer when buying a home. 

Air-O-Cell sample bottle
Graphic depicting how the Mold testing Air O Cell works during the mold inspection

What kind of sampling is right for you?

In most circumstances, we recommend taking air samples:

  • Air samples collect material from the whole room including out-of-sight areas such as vents or ducts. 

  • Breathing in moldy air causes health problems so we recommend checking the air.

  • The air has more living mold and living mold is more harmful. Surfaces may have higher amounts of mold, but much of it is likely to be inactive or dead.

  • If you can see mold growing, you know it's mold, so why test? 

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In specific situations, surface samples are suggested:

  • If you know you have sensitivities or allergies to a particular strain of mold and know where mold is definitely present.

Indoor Air Quality Association (IAQA) logo
Mold Lab Certification seal

Mold in Your Home: Mold FAQS 101

"Mold spores are literally everywhere; controlling moisture is the key to preventing their growth. Sources within homes, businesses, and schools include leaks through roofs, walls, and basements; condensation on windows and in bathrooms; standing water in drains, on floors, and in heating, cooling, and dehumidifying equipment; heating/cooling ducts; and wet floors and carpets. Preventing mold growth requires preventing leaks, removing standing water, venting areas prone to condensation (especially bathrooms and kitchens), and immediately drying or removing damp carpets and furniture. Mold-inhibiting paints can be used indoors, and air conditioners and dehumidifiers can be used in humid weather. (Poison.org)"

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To find mold that might be growing in your home (HUD.gov):

  1. "Search for moisture in areas that have a damp or moldy smell, especially in basements, kitchens and bathrooms.

  2. Look for water stains or colored, fuzzy growth on and around ceilings, walls, floors, windowsills and pipes.

  3. If you smell a musty odor, search behind and underneath materials such as carpeting, furniture or stored items.

  4. Inspect kitchens, bathrooms and basements for standing water, water stains and patches of out-of-place color.

  5. To control moisture problems and mold:

  6. Fix any water problems immediately and clean or remove wet materials, furnishings or mold.

  7. Clean up spills or floods within one day. If practical, take furniture that has been wet outside to dry and clean. Direct sunlight prevents mold growth.

  8. Dry all surfaces and fix the problem or leak to prevent further damage.

  9. Install a dehumidifier when a moisture problem is evident or when the humidity is high."

Offering mold inspections and sampling to Pennsylvania, Delaware, and Maryland.​

(302) 993-9100

Photo of Moldy cheese  advertising Reliable Home Inspection Service Mold Testing

How is a Mold Air Quality Assessment performed?

With an air sample test, we take three samples. The first sample is of air outside the home. There’s a little bit of mold around us all the time, so we want to be able to compare the general mold environment with the air in the home specifically.

 

We use the second two samples to check rooms in the home. If you have specific places you'd like us to test, for example, a room with an odd odor with no visible cause that’s the room we’ll test. If you’re aware of a history of mold in any part of the home we’ll check there instead.

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If you don't have a specific room in mind we'll usually test the bedrooms, where people spend the most time, and/or the basement which is prone to moisture. 

Mold Testing InfoJohn Kerrigan
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Drawing of microscope looking at mold spore

How our reports look 

Your Mold Report 

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Mold spores in every home. The real question is weather your indoor air has more mold, or different kinds of mold than the air outside. That is what a mold air test measures.

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When we test, we take one sample outdoors as a baseline and one or more samples inside your home. Sn accredited independent laboratory counts and identifies the spores in each sample. Then it compares the indoors results to the outdoor baseline. 

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Your report may look technical, but you only need to know a few things to read it. 

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Start Here: The Determination Row 

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The most important line on your report is Determination. It sists near the top of the results table, under each sample. It is the labs bottom-line answer each room. 

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Reading the rest of the results table. ​

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Spores m³ is the number to focus on. It shows how many mold spores were in one cubic meter of air. Compare each indoor room to the outdoor sample.

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Raw count is how many spores the lab physically counted on the slide. The lab converts it into spores per m³. You can skip this Colum.  

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Total spores adds up every type found in that sample. Indoor totals at or below the outdoor total are a good sign. 

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Precent of Total shows what share of each sample each mold type makes up. It helps the lab see whether indoor air has a different mix than outdoor air. 

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Minimum Detection Limit is the smallest amount the lab can measure from the volume of air collected. Anything below it would not show up. 

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Background Debris rates how much dust and other particles were on the sample. Light or Moderate means the count is reliable. Heavy or too heavy means some spores may have been hidden, so the real count could be higher. 

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If a mold isn't listed, it wasn't found. The lab only list what it observed 

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Common mold types you may see ​

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Water - damage indictor molds

Some mold usually grow only where materials have stayed wet. These include Stachybotrys (often called "black mold"), Chaetomium, Fusarium, Memnoniella, scopulariopsis and Ulocladium. Finding these indoors, even in small numbers, is a reason to look for a leak or moisture source. 

"Why is one mold higher inside than outside?"

This is the question we hear most. It's common to see Penicillium/Aspergillus a little higher indoors, even on a report marked Not Elevated. 

Here's why. Outdoor air carries many types of mold. Your walls, windows and filters keep most of them out. Penicillium/Aspergillus is the type most often found in normal indoor air, so it tends to make up most or all of an indoor sample. 

The lab looks at the whole picture: total spore levels, the mix of types, and how your results compare to thousands of other homes. A small difference at low counts is normal variation. That's why lab can still rate a room Not Elevated.


A much larger difference, or a room rated Elevated, is worth a closer look. 


The charts and reference pages 

Comparison charts show each indoor room next to the outdoor sample, one mold type per row. The indoor sample and the Outdoor sample are shown as two different colored bars. They show the same numbers as the table in picture form.

Mold species information at the end of the report describes each mold type found: where it usually grows and it's allergy potential. This general background, not a fining about your home. 


What a clean air test does and doesn't tell you

An air test is a snapshot of the air in that room on the day we tested. A Not Elevated result is reassuring, but it can't rule out a small, sealed problem behind a wall or under flooring. 

If you see staining, notice a musty smell, or know of past leaks, have a specific area evaluated even if the air test is clean. 


There are no federal standards for safe indoor mold levels. Your repost compares your indoor air to the outdoor air and to the lab's database. It is not a medical or health rating. If you have health concerns, talk to your doctor. 

How to book a mold testing appointment in Wilmington?

To book a mold test in Wilmington or any other part of Delaware (and select areas of Pennsylvania and Maryland), please contact the Reliable Home Inspection Service office at 302-993-9100 or at info@reliablehomeinspectionservice.com.

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Our staff will be happy to provide additional information, pricing and coordinator your Mold Test.

Contact us for Information about Mold Testing

Frequently asked questions  

Is any amount of mold in my home a problem? 
No. Mold spores are a normal part of indoor air. What matters is weather indoors levels or types are higher than expected compared to outside. 

My report says Not Elevated. Do I need to do anything? 
Usually not. If you still notice a musty odor, visible growth or water stains, have that area checked. The air test dose not replace a visual inspection of a known problem. 

My Repost says elevated. What now?
We use an independent, accredited microbiology. The lab has no stake in the results, and it's accreditation means it's methods are checked regularly.  


Why is the sample sent to a lab in another state?
We use an independent, accredited microbiology laboratory. The lab has no stake In the results, and it's accreditation means it's methods are checked regularly.

Is Penicillium/Aspergillus dangerous?
It is one of the most common molds in any home. Like many molds, it can trigger allergy or asthma symptoms in sensitive people.

Will you retest after remediation? 
Ask us about post- remediation air testing. We recommend waiting until the work and any drying are fully complete. 

Question about your repost? Call us 
Reliable Home Inspection Service has served Delaware, Pennsylvania and Maryland for more than 32 years. John Kerrigan is an active IAOA - Indoor air Quality Association. If anything on your mold report is unclear, call us at (302)993-9100. We'll talk you through it.  

 

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