Daniel Friedman, Air Quality Test Expert

Daniel FriedmanDaniel Friedman has an extensive, highly-impressive resume. He currently works as a forensic microscopist specializing in indoor environmental problem detection, diagnosis and recommendations for repair. He has a bachelor of science from Washington & Lee University and belongs to numerous membership societies, including the American Society of Home Inspectors and the Pan American Aerobiology Association.

Daniel does not perform actual remediation nor repair work, but instead, provides both field investigation and laboratory services and operates a forensic laboratory in Poughkeepsie, New York, and San Miguel de Allende, Mexico. Daniel is a professional writer and educator in the field of building inspection, diagnosis, and repair, and publisher of a consumer information website InspectAPedia.com, which provides building and environmental problem diagnosis and repair advice. To top it all off, Daniel has numerous publications to his name, which may be referenced on the InspectAPedia website.

How did you get started in the field of air quality?
After nearly 30 years of building inspection and construction experience, and with a long interest in technical investigations I was asked by a city health department to investigate the cause and effects of an indoor moisture and mold problem at a public housing project. I followed courses of professional education offered by faculty from the Harvard School of Public Health, the American Industrial Hygienists Association and the McCrone Research institute - the world's leading educator in the field of forensic and biological microscopy. The content of these courses expanded my interest in the methods and equipment used to examine the indoor environment, leading to my own role as a writer and educator in the IAQ field.

Why is it important for people to have their air tested?
People should not have their air tested unless that test is performed as a part of a more thorough visual inspection and diagnosis of a building that is called for when people have already noted a reason for concern, such as health complaints that appear to be building-related or the visual observation of a large area of mold contamination that merits professional cleanup as well as meriting the diagnosis of the cause and thus the necessary steps to cure that condition. See http://InspectAPedia.com/sickhouse/investigate.htm for an article that helps consumers decide when it is appropriate to hire an expert.

Air testing alone is fundamentally unreliable as a screen for building mold problems, and is at high risk of providing a "false negative" result, missing important mold or other airborne particle contaminants. The level of airborne particles varies by several orders of magnitude depending on many site variables as well as just how the test is conducted. See http://www.inspect-ny.com/sickhouse/IAQMethods.htm for an article comparing various indoor air quality test methods and describing the strengths and weaknesses of each.

How do you test indoor air quality? What types of equipment are necessary for an inspection?
I start with a detailed client interview, including their complaints, building-related complaints, as well as taking a history of their occupancy of the building and information about the building itself, its age and materials.

I perform a very detailed visual inspection of the entire building, outside and inside, not only looking for evidence of visible IAQ concerns, but equally important, I look for building conditions, materials, construction details that area associated with IAQ concerns or that may cause them (such as the building leak and water entry history, ventilation problems, insect damage, use of chemicals).

I collect identification samples where large areas of visible mold are observed, screening samples of building dust and debris, and possibly other building test samples using a variety of methods and equipment such as adhesive tape (see http://www.inspect-ny.com/sickhouse/bulksamp.htm for procedural details), vacuum samples of porous materials (such as building insulation that may be mold contaminated but looks clean - see http://www.inspect-ny.com/sickhouse/FiberglassMold.htm), and screening or reference samples of indoor air and airborne debris, using an aggressive sampling method (stirring local dust) as well as similar samples in or on air handling equipment such as A/C duct work or air handlers.

What types of hazards do you look for when testing a home or business?
Because the number of potential building contaminants is enormous and tests could easily waste client money, we start by identifying the more likely hazards based on the interview and visual inspection that point to targets or typical complaints. Visible mold, pet allergens, etc. may be visually obvious or may be suggested by the case history. But we consider gas hazards, particularly unsafe venting of combustion gases from heating equipment (starting with a visual inspection of the equipment and chimneys), and we are alert for chemical hazards based on the site or building history (such as owner-performed termite treatment). We need to be alert for special conditions that may be less obvious to a novice such as an apartment affected by CO from idling cars from a public garage located just below or adjoining). When necessary, we can use broad-spectrum screens for indoor gases or chemicals, but usually this is not a cost-effective approach.

How can a consumer tell if they have an indoor air quality problem? Are there any signs consumers should be cautious of?
Building-related complaints are important to investigate further.

A visual inspection by an experienced, trained expert is very important, particularly because some hazards, such as CO, are intermittent and could be present at fatal levels at some moments but totally absent at others.

Do you have any advice or suggestions for people who wish to get their air tested?
Do not start with nor rely on air testing alone to screen buildings for IAQ problems. Start with an interview by and visual inspection by an expert.

Do you have any advice or suggestions for people who are considering a career in the air testing field?
Do not rely on weekend or correspondence courses on IAQ nor mail order certifications. A competent inspector must understand how buildings work, where problems on buildings occur, as well as understanding the characteristics of each tool and method used in IAQ investigations. Listen to the client, inspect the building and think independently.

If you would like to learn more about air quality tests, read Tests.com’s Air Quality Test Guide. To find an air quality test professional, visit our Air Quality Test Directory.


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