Using Vacuum Cassettes or Spore Traps to Collect Mold or Particle Dust Samples: Guide to Good Practices
InspectAPedia^® -

Field testing vacuum cassettes to collect building dust as a screen for toxic or allergenic mold contamination indoors
Guide to use of vacuum cassettes to screen building soft surfaces, furniture, carpeting
Guide to use of vacuum cassettes to collect multiple dust samples in buildings

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers nor with topics or services discussed at this website.

This article explains the advantages and shortcomings of using vacuum cassettes or spore traps to collect mold test samples (or other dust or particle samples) from indoor surfaces such as carpets, couches, or multiple hard surface dust samples. In this article series discuss the validity of nearly all of the popular mold testing methods currently in use, pointing out the strengths and weakness of each approach to mold sampling in the indoor environment, beginning with air sampling for airborne mold levels indoors. Because mold test validity and mold test accuracy are often confused, readers should also see ACCURACY OF VARIOUS MOLD TEST METHODS. People who need to conduct mold inspection and testing indoors should see MOLD TEST PROCEDURES and TECHNICAL & LAB PROCEDURES

Our MOLD INFORMATION CENTER includes more broad discussions of the overall approach to building investigation, as do many expert references cited at that web. For a more comprehensive collection information about mold test methods see INDOOR AIR QUALITY METHODS COMPARED. For more on "mold classes" (Cosmetic mold vs. allergenic mold vs. toxic or pathogenic mold) see MOLD CLASSES, HAZARD LEVELS and more references such as a Mold Action Guide are at the end of this document.

© Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

A Guide to Using Vacuum Samples for Screen Buildings for Toxic Mold

15th Annual North Carolina/South Carolina
Environmental Information Association Technical Conference
Myrtle Beach, SC
Daniel Friedman 23 September 2005, Updated 4/14/2009

A collection canister is connected to an air or vacuum pump which is used to draw particles onto a filter-surface or into a special collection container.

A collection device, slide, cassette, or tape are used with a calibrated air pump to collect surface particles.

The lab prepares a slide from the cassette (of the types below) or if an MCE filter cassette was used to collect particles, the lab clears the filter onto a microscope slide, washes the filter onto a microscope slide, or uses another method to transfer particles for examination by microscope for preparation by culture.

Using a simple portable pump calibrated to a known flow rate allows rough estimation of particle density per square inch of surface tested if that analysis is needed.

People using this approach may make use of a disposable paper square template that defines a precise surface area to be vacuumed (photo above left). In our opinion a precise quantitative approach to surface vacuuming is silly because there is normally large particle variation over building surfaces for many reasons. But the approach is useful to screen for high levels of particular particles (such as mold spores, animal dander, insect allergens).

Our photo (left) shows five vacuum test areas on a hallway carpet during a study conducted by the author to examine the variation in particle deposition by foot traffic in a residential hallway.

Our hypothesis was that more outside dirt and debris could always be found in the center of the main path of foot traffic even though that area also received more aggressive vacuum cleaning than the hallway sides. We have tested carpeting before and after various types of cleaning and after suffering various types of contamination.

Surface vacuuming for mold

We emphasize that in this article we are discussing surface vacuuming to collect particles from an exposed surface onto which the vacuum device and collector can be placed directly.

This is an effective and useful particle or mold sampling method.

We are not referring building wall or ceiling cavity vacuuming methods that attempt to draw air and particles from the building cavity through a punctured opening and tube into a collecting device - an approach that our test found was ineffective.

We discuss building cavity vacuuming below at Vacuuming building cavities.

Vacuum samples can be useful for testing soft goods (clothing, bedding, curtains, carpets) for high levels of contaminated spores in a qualitative approach. We particularly like vacuuming a number of surfaces in an area using a single collection device as a less-costly way to make a more confident inspection of the level of contamination by moldy dust in buildings with a known problem.

We also use this method as part of a mold clearance inspection to evaluate the thoroughness of both the containment system and the general cleaning effort. For example we may collect a sample of vacuumed surface dust from 10 different surfaces in 5 rooms on a floor of a home, forming a more broad screen for moldy dust than single tape lifts of surface dust.

We've found wide variety in levels of mold found growing in or on carpets, depending on a number of variables including even the level of other dirt present in the carpeting. Some experts question this measure. Carpet vacuuming for mold is interesting as a pre and post remediation baseline data source for areas out of the remediation/containment area, but for any carpet this method quickly overloads a particle sampler.

The Burkard personal air sampler (photo at left) can also be used to vacuum particles from surfaces provided that a strong air flow is not required to lift the particles from the surface (this device pumps at 10 lpm).

Shortcomings of surface and carpet vacuuming for mold

Vacuuming will not collect identifying structural components of mold as well as tape and will almost certainly damage or destroy the structures which it collects, imposing some limits on identification
Vacuuming will not collect all of the material on a hard surface (which tape handles well). Particles which are easily lifted by the airflow into the canister will be over-represented compared with sticky particles which are adhered to the test surface.

This problem is particularly sensitive to the flow rate (LPM) used. A low-flow rate (1LPM) avoids a sample overload problem (too many particles, can't read the sample) but may fail to collect or under-collect certain particles. A high flow rate improves particle pick-up but then limits the number of sample sites (increasing test cost) in order to avoid sample overload. We suspect that no vacuum method we have tested could reliably pull mold or debris reliably from deep inside a heavy upholstered couch.
Carpet vacuums and some furniture or drapery vacuums will either be overloaded or restricted to culture (to which we have already objected).

Questions & Answers regarding this article

Ask a Question or Search InspectAPedia

HTML Comment Box is loading comments...

Recommend / Share this Article

...

Technical Reviewers & References

InspectAPedia.com^® - Daniel Friedman - Publisher & Editor.
InspectAPedia Bookstore lists recommended books, organized by topic & available for purchase. Most of our articles also include a list of recommended books for the specific article topic as well as other references, and information sources.
Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
Additional technical contributors & reference sources for this article are listed below.

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

MOLD TESTING METHOD VALIDITY
  Air samples
    Shortcomings of air sampling
    Mold in Air: Quantitative Analysis
  Tape sampling for mold
    Determination of mold genera
    Determination of mold species
    Shortcomings of tape sampling
  Vacuum samples
    Surface vacuuming
    Shortcomings of surface and carpet vacuuming
    Vacuuming building cavities
    Vacuuming exposed insulation
    Shortcomings of vacuuming insulation
  Cultures to "Test for Mold"
    Shortcomings of culturing
  Swab sampling
  Shortcomings of swab sampling
  PCR methods for Mold Identification
  MOLD TEST vs. PROBLEM DIAGNOSIS
  Are Mold Test Kits Useful?
  Reasons to Test for or Identify Mold
    1. Save Money if it's Just Cosmetic Mold
    2. Mold Related Illness
    3. Mold Cleanup Data baseline

Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. (727) 595-4211 mark@BestTampaInspector.com

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.

Environmental Health & Investigation Bibliography - our technical library on indoor air quality inspection, testing, laboratory procedures, forensic microscopy, etc.

Adkins and Adkins Dictionary of Roman Religion discusses Robigus, the Roman god of crop protection and the legendary progenitor of wheat rust fungus.

Kansas State University, department of plant pathology, extension plant pathology web page on wheat rust fungus: see http://www.oznet.ksu.edu/path-ext/factSheets/Wheat/Wheat%20Leaf%20Rust.asp

"A Brief Guide to Mold, Moisture, and Your Home", U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm

US EPA - Mold Remediation in Schools and Commercial Building [Copy on file at /sickhouse/EPA_Mold_Remediation_in_Schools.pdf ] - US EPA

US EPA - Una Breva Guia a Moho - Hongo [Copy on file as /sickhouse/EPA_Moho_Guia_sp.pdf - en Espanol

Allergies, Allergens, Allergy Testing in Buildings - References & Products

Air Conditioning System Blower Fans & Filters Cascading for Optimum Indoor Air Quality

Allergen Tests in Buildings advice about how to test, what to look for, in evaluating the level of dog, cat, or other animal allergens in a building

"IgG Food Allergy Testing by ELISA/EIA, What do they really tell us?" Sheryl B. Miller, MT (ASCP), PhD, Clinical Laboratory Director, Bastyr University Natural Health Clinic - ELISA testing accuracy: Here is an example of Miller's critique of ELISA http://www.betterhealthusa.com/public/282.cfm - Townsend Letter for Doctors and Patients
The critique included in that article raises compelling questions about IgG testing assays, which prompts our interest in actually screening for the presence of high levels of particles that could carry allergens - dog dander or cat dander in the case at hand.
http://www.tldp.com/issue/174/IgG%20Food%20Allergy.html contains similar criticism in another venue but interestingly by the same author, Sheryl Miller. Sheryl Miller, MT (ASCP), PhD, is an Immunologist and Associate Professor of Basic and Medical Sciences at Bastyr University in Bothell, Washington. She is also the Laboratory Director of the Bastyr Natural Health Clinic Laboratory.

Allergens: Testing for the level of exposure to animal allergens is discussed at http://www.animalhealthchannel.com/animalallergy/diagnosis.shtml (lab animal exposure study is interesting because it involves a higher exposure level in some cases

Allergens: WebMD discusses allergy tests for humans at webmd.com/allergies/allergy-tests

Animal Allergens: Dog, Cat, and Other Animal Dander - Cleanup & Prevention Information for Asthmatics and regarding Indoor Air Quality.

Atlas of Mold Related Illness Symptoms & Complaints - long list of both documented, studied mold related illness, and complaints ascribed to mold contamination or allergens in buildings

Cat Dander: how to inspect and test a building for past or current presence of cats, cat hair, cat dander, and cat allergens

Clinical Atlas of Mold Toxicity - An Online Description of Toxic, Pathogenic, Allergenic Fungi, Fungal Diseases

Fiberglass Insulation Contains Mold© 2005 comments about a field study in process, & more about health hazards from fiberglass insulation

Humidity: What indoor humidity should we maintain in order to avoid a mold problem?

Mold Action Guide detailed guide on finding, removing, and preventing indoor mold contamination

Odors, Odor Detection, Smells, & Gases how to find and identify sources of noxious or toxic odors and gases

Other environmental risks, Our much longer list: Asbestos, carbon monoxide, electromagnetic fields, etc.

Ozone: The Use of Ozone Indoors for Control of Odors and Mold Removal in Buildings: A Summary of Hazards and False Claims.

Pollen Allergens: identification, plant pollen and indoor air quality

Products to Reduce Mold & Allergy Problems to reduce indoor mold or allergen levels: air cleaners, air purifiers, dust mite covers, vacuum cleaners, crawl space vents

Recognizing Allergens: What various indoor allergens look like - identification photos to help identify pollen, dust mites, animal dander, toxic or allergenic mold - Common Mold and other Allergens, Irritants, Remedies & Advice

Rodent control issues, including dander, fecal, and urine contamination of Buildings and Building insulation are discussed at our

Sewage and Septic backup contamination in Buildings: inspection, testing, remediation, & references to expert sources

Action Guide: What to do about mold, mildew, and other indoor allergens

...

Mold Contamination Testing, Cleanup, Prevention: references & products

The Mold Information Center: What to Do About Mold in Buildings, When and How to Inspect for Mold, Clean Up Mold, or Avoid Mold Problems

Aerobiology, Building Science, Microscopy, & Laboratory References, an extensive technical bibliography

Allergens: what they look like in buildings

Associations: Sick House, Sick Building, SBS - Air Quality, Government, Private Associations and Information Resources

Atlas of Clinical Fungi, 2nd Ed., GS deHoog, J Guarro, J Gene, & MJ Figueras, Centraalbureau voor Schimmelcultures, Universitat Rovira I Virgili, 2000, ISBN 90-70351-43-9 (you can buy this book at Amazon) - The Atlas of Clinical Fungi is also available on CD ROM

Atlas of Mold Related Illness: Index of Symptoms and health, physical, neurological, psychological, and other complaint which people suspect may be mold or building-related.

Atlas of Indoor Mold, Online Clinical Mold Atlas, Toxins, Pathogens, Allergens and Other Indoor Particles - Medical Health Effects of Mold (separate online document)

Black Mold that is Harmless Photos of recognizable, usually harmless black mold on wood, bluestain, ceratocystis, ophistoma

Building Floods: quick steps after a building flood or plumbing leak can prevent costly mold contamination

Classes of Mold: what types of cosmetic, allergenic, or toxic mold are a problem? Can mold be cleaned-up successfully?

Clinical Mold References - Detailed bibliography of mold reference texts

"A Brief Guide to Mold, Moisture, and Your Home", U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm

"Disease Prevention Program for Certain Vegetable Crops," David B. Langston, Jr., Extension Plant Pathologist - Vegetables, University of Georgia (PDF document) original source: www.reeis.usda.gov/web/crisprojectpages/209797.html

"Disease Prevention in Home Vegetable Gardens," Patricia Donald, Department of Plant Microbiology and Pathology, Lewis Jett
Department of Horticulture, University of Missouri Extension - extension.missouri.edu/publications/DisplayPub.aspx?P=G6202

"Management of Powdery Mildew, Leveillula taurica, in Greenhouse Peppers," Ministry of Agriculture and Lands, British Columbia - Original source: www.agf.gov.bc.ca/cropprot/peppermildew.htm

Environmental Health & Investigation Bibliography - our own technical library on indoor air quality inspection, testing, laboratory procedures, forensic microscopy, etc.

Fiberglass: Mold in Fiberglass Insulation© 2005 comments about a field study in process, & more about health hazards from fiberglass insulation - DJF

Fifth Kingdom, Bryce Kendrick, ISBN13: 9781585100224, is available from the InspectAPedia online bookstore - we recommend the CD-ROM version of this book. This 3rd/edition is a compact but comprehensive encyclopedia of all things mycological. Every aspect of the fungi, from aflatoxin to zppspores, with an accessible blend of verve and wit. The 24 chapters are filled with up-to-date information of classification, yeast, lichens, spore dispersal, allergies, ecology, genetics, plant pathology, predatory fungi, biological control, mutualistic symbioses with animals and plants, fungi as food, food spoilage and mycotoxins.

Fungi, Identifying Filamentous, A Clinical Laboratory Handbook, Guy St-Germain, Richard Summerbell, Star Publishing, 1996, ISBN 0-89863-177-7 (English) (buy at Amazon)

Looking for Mold Procedure: what mold is often found where in buildings - simple technical presentation

Meruliporia: the house eating fungus or "poria"

Mold Action Guide: Step-by-Step Instructions, What to do about mold, mildew, and other indoor allergens

MOLD APPEARANCE - WHAT MOLD LOOKS LIKE Photos of what mold looks like in buildings

MOLD APPEARANCE - STUFF THAT IS NOT MOLD Photos of NOT-mold material that is sometimes mistaken for mold

MOLD ATLAS & PARTICLES INDEX, Pathogens, Allergens and Other Indoor Particles - Medical Health Effects of Mold (separate online document)

MOLD BY MICROSCOPE Mold under the microscope - photo identification of the most common indoor molds found in buildings

Mold FAQs Answers to Most Questions about Indoor Mold, Mold Related Illness, Mold Cleanup, Mold Prevention

US EPA: Mold Remediation in Schools and Commercial Building [Copy on file at /sickhouse/EPA_Mold_Remediation_in_Schools.pdf ] - US EPA

Mold spores in the Home - a Photo ID Library for detection and identification of mold allergens

Mold Test Kits - How to Collect and Send Your Own Mold Sample to our mold testing lab or to any mold lab you wish

Most Common Indoor Molds Found in Buildings, A Table of

Mycology, Fundamentals of Diagnostic, Fran Fisher, Norma B. Cook, W.B. Saunders Co. 1998, ISBN 0-7216-5006-6 (buy this book at Amazon)

Ozone Warnings - Use of Ozone as a "mold" remedy is ineffective and may be dangerous.

Rot concerns in buildings-some building mold such as Meruliporia incrassata "Poria" risks serious rot and hidden structural damage

US EPA: Una Breva Guia a Moho - Hongo [Copy on file as /sickhouse/EPA_Moho_Guia_sp.pdf - en Espanol

OTHER IAQ ISSUES: How To Find and Address Other Indoor Air or Indoor Environment Contaminants Besides Mold

Mold or allergens may not be the only or even the main indoor environmental contaminant. Don't let media attention to mold cause so much enviro-scare fear that other, possibly more urgent hazards go un-addressed.

Fiberglass building insulation and HVAC duct work insulation hazards

Sewage and Septic backup contamination in buildings: inspection, testing, remediation, & references to expert sources

Other environmental risks: Asbestos, carbon monoxide, electromagnetic fields, environmental illness, fiberglass, MCS - multiple chemical sensitivity, toxic gases, etc

Indoor Gas Sampling Plan for Residential Buildings lists a number of toxic indoor gases which we test for, depending on the building complaint and building conditions

Ozone Warnings - Use of Ozone as a "mold" remedy is ineffective and may be dangerous.

Pet control - if you can't say goodbye to your bird, cat, dog, guinea pig, hamster, tropical fish, then limit the areas they occupy and limit the airflow from that area to sleeping or other areas of the building, use allergenic bedding, eliminate wall-to-wall carpeting, improve housecleaning including use of a HEPA-rated vacuum cleaner. For more details see our article Dog, Cat, and Other Animal Dander - Information for Asthmatics and Indoor Air Quality

Rodents, Mice, Squirrel Control - I find high levels of mouse and rodent dander, fecal dust, and urine-contaminated dust in some buildings, and high levels of these materials in building insulation in those locations. If you have a mouse problem, particularly if mice and their waste (fecals or urine) are contaminating the building HVAC or building insulation, may need both steps to clean up or remove infected materials and steps to stop an ongoing rodent problem. If squirrels are a problem, the cleanup needs to include closing off entry openings into the building. Get some help from a licensed pest control expert.

Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair

Ask a Question or Search InspectAPedia

A Guide to Using Vacuum Samples for Screen Buildings for Toxic Mold

Surface vacuuming for mold

Shortcomings of surface and carpet vacuuming for mold

Questions & Answers regarding this article

Ask a Question or Search InspectAPedia

Technical Reviewers & References

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

Allergies, Allergens, Allergy Testing in Buildings - References & Products

Mold Contamination Testing, Cleanup, Prevention: references & products

OTHER IAQ ISSUES: How To Find and Address Other Indoor Air or Indoor Environment Contaminants Besides Mold