Mold Testing and Bacteria Testing

Trusted Laboratories

Trusted Laboratories

Phone: (905)290-9101
Toll Free: 1-866-813-0648

Worried About Mold?

Click ** Get Your Free Assessment Now!**

  • Home
  • About Us
  • Services
    • Mold Testing
    • Bacteria Testing
    • Legionella Testing
    • Cannabis Testing
    • Antimicrobial effectiveness testing
    • Biological Indicators and Sterilization Process
    • Contract Microbiological Research
    • Environmental Monitoring & Bioburden Testing
    • Material Fungus Resistance Testing
    • Materials Standard Testing
    • Cannabis Licence
  • Accreditation
  • Mold Test Kits
  • View Courses
  • Freebies
    • Live Presentations
    • FREE Mold Inspection Quiz
    • FREE Mold Spore Identification Quiz
  • Resources
    • Chain of Custody Form
    • Ask a Question
    • How to Take Samples
    • Results Interpretation
    • Mold and Bacteria Pictures
    • Jobs
  • Contact us
You are here: Home / Mold / Methods for Investigation and Evaluation of Mold Related Problems

Methods for Investigation and Evaluation of Mold Related Problems

Dr Jackson Kung'u

Investigations and evaluation of mold related problems rely on sampling techniques to determine the presence or absence of mold growth. In the indoor environment presence of mold is an indirect indicator of the occupants’ potential exposure to those molds. There are several mold sampling methods and understanding the advantages and disadvantages of each method is important. Each sampling method has its advantages and disadvantages, meaning that no single method is capable of fully answering all the investigation questions. Therefore, a complex mold investigation may require more than one sampling method. Before choosing a sampling method, it’s important to understand what kind of data each method can provide and how to interpret that data. You may want to learn more about our mold inspection and control course.

Methods for Sampling of Indoor Mold

Air sampling methods (culture plates, spore traps)

When people talk of spore traps they refer to air sampling using filter membranes or adhesive-coated slides such as Air-O-cell, Allergencos or Micro 5. However, sampling air using culture plates is also a form of spore trapping. Results for spore traps are reported as number of spores per cubic meter of air (spores/m3). One big disadvantage for spore traps is that the mold types can only be identified to genus level and a significant number of spores may have to be reported as “unidentified spores”. 

Results of samples collected using culture plates are reported as number of colony forming units (cfu) per cubic meter of air (cfu/m3). The advantage of culture plate sampling is that the types of mold present can be identified to species. A few molds may fail to produce spores that aid in identification. Such molds are reported as “non-sporulating isolates (NSI).

Dust Sampling

When mold releases spores into the air the spores end up settling on surfaces such as those of the carpet. When the carpet is disturbed these spores together with dust are re-suspended in the air and are inhalable into the lungs and can induce adverse health effects. Sampling of carpet dust will give us an idea of the amount and types of spores present on the carpet. Spores can also be brought into the building through soiled articles such as shoes. Results for dust samples are reported as number of colony forming units (cfu) per gram of dust (cfu/g). The recovered molds can either be identified to genus or species.

Surface Swab and Wipe Sampling

visible mold growth
Visible Mold Growth

Surfaces can be sampled for mold contamination using either a swab or wipe. This method is particularly useful when there is no visible mold growth. The results are reported as colony forming units (cfu) per square inch (cfu/inch2) or per square centimeter (cfu/cm2). The recovered molds can be identified to genus or species.

Tape Lift and Bulk Sampling

Tape lift sampling is the recommended method for sampling visible mold growth. If the surface being sampled is wet, then bulk or swab/wipe sampling should be used. The purpose of tape lift and bulk sampling is to determine the type of molds present. Results are provided as a list of the molds identified in rank order. The ranking is rather subjective and depends on which areas of the slide the analyst scanned. If sampling large areas of mold contamination, it’s important to collect more than one sample because a single sample may not be a good representative of the diversity of molds present in the building.

While some labs try to quantify the amount of mold on tape lift and bulk samples, such data is often not only inaccurate and misleading but it is also of no practical use.

author avatar
Dr Jackson Kung'u
Dr. Jackson Kung’u is a Microbiologist who has specialized in the field of mycology (the study of moulds and yeasts). He is a member of the Mycological Society of America. He graduated from the University of Kent at Canterbury, UK, with a Masters degree in Fungal Technology and a PhD in Microbiology. He has published several research papers in international scientific journals. Jackson has analyzed thousands of mould samples from across Canada. He also regularly teaches a course on how to recognize mould, perform effective sampling and interpret laboratory results. Jackson provides how-to advice on mould and bacteria issues. Get more information about indoor mould and bacteria at www.drjacksonkungu.com.
See Full Bio
social network icon social network icon

No related posts.

Filed Under: Mold Tagged With: air sampling, dust sampling, surface sampling, visible mold growth

How Much Do You Know About Mold?

Take a 3 minutes Quiz and find out how much you know about mold. To start the Quiz please Click START QUIZ below.

General Knowledge Mold Quiz

General knowledge mold quiz- Try it, it's fun!
Complete the form below to see results
Share your result via
Facebook X Pinterest LinkedIn Email

By the way, we have online mold courses at https://www.mytrainingcourses.ca

« NIOSH Mold and dampness assessment tool
Medical Relevance of Cladosporium Spores In Indoor Environment »

Online Training

Online Mold Recognition, Assessment
And Control Course. Register Today!

Mold Testing Kits

FREE Homeowners eBook!

Bacteria Testing

Microbiology Testing Lab offering identification of environmental bacteria!

Legionella Testing

Legionella Testing by CALA-accredited laboratory. Call Today!

Laboratory Mold Testing

Mold Testing Laboratory and Indoor Air Quality Analysis!

Mold Inspection Services

As Mold Inspection Specialists, We
Are Who To Call For Mold Inspection!

Recent Posts

Is E. coli Airborne? Separating Facts from Myths in Bacterial Sampling

In the world of indoor environmental quality, bacterial contamination often raises questions, especially when dealing with sewage damage. A recent … [Read More...]

 - Mold Testing and Bacteria Testing

Is “Black Mold” Equivalent to “Toxic Mold”?

Is "Black Mold" Equivalent to "Toxic Mold"? No, black mold is not equivalent to toxic mold. "Black Mold" is a term that is often used incorrectly to … [Read More...]

 - Mold Testing and Bacteria Testing

Exploring Non-Tuberculous Mycobacteria (NTM): Understanding Characteristics and Implications

What Are Non-tuberculous Mycobacteria (NTM)? Non-tuberculous Mycobacteria are mycobacteria other than Mycobacterium tuberculosis and M. leprae, and … [Read More...]

Learn With Us…

Courses

  • Mold Inspection, Identification and Control
  • Fungal Spore Identification
  • Mold Inspection Business Course
  • How to take Mold Samples Course
  • Coliform Testing
  • WHMIS
  • INTERESTING KNOWLEDGE QUIZES

Get In Touch

By phone or by email
905-290-9101
Email

Our Location
1020 Brevik Place, Unit 1A • Mississauga, ON L4W 4N7
(Phone: 905-290-9101 • toll-free: 1-866-813-0648 • fax: 905-290-0499.)

  • Email
  • Facebook
  • LinkedIn
  • Twitter
  • YouTube

Search this Site

Recent Posts

  • Is E. coli Airborne? Separating Facts from Myths in Bacterial Sampling
  • Is “Black Mold” Equivalent to “Toxic Mold”?
  • Exploring Non-Tuberculous Mycobacteria (NTM): Understanding Characteristics and Implications

Useful Links

  • Chain of Custody Download
  • Contact us
  • Privacy policy

Copyright © 2025 · Mold & Bacteria Consulting Laboratories. Log in