Montrose 4/1/2014 4:27:42 PM
News / Random

Top Six Mold Testing Mistakes To Avoid, Recommends Environmental Hygienist Fry

“Mold testing results, as done by many mold inspectors and industrial hygienists, are often inaccurate and misleading because of a number of mold testing mistakes and problems,” warns Phillip Fry, Certified Environmental Hygienist, Professional Industrial Hygienist, and author of five mold advice ebooks, who explains these top six mold testing mistakes or misconceptions:

The most basic problem is that “Standards for judging what is an acceptable, tolerable, or normal quantity of mold have not been established,” according to the Centers for Disease Control on its website.

Second, the training of most mold inspectors is very limited and inadequate, with the result that their primary functions are only to: (a) collect air samples and physical mold samples; (b) send the samples to a mold laboratory for mold species identification and quantification; and (c) compare indoor test lab results with an outdoor control air test.

Most mold inspectors and industrial hygienists do not have adequate training, experience in the science, techniques, and procedures utilized in mycology (fungal biology) and microbiology (study of microscopic forms of life such as bacteria, viruses, and fungi), such as utilizing the U.S. E.P.A.’s data quality objectives or “DQO” (in developing each property’s mold inspection and testing protocol), which are explained at

For example, the DQO for the mold testing of a residence might be “Are occupants exposed to indoor mold levels greater than.…(the typical mold levels in that particular geographical area for houses with low mold levels)?”

Third, most initial mold inspections do not require any air mold tests but only very careful physical inspection of the home or business building to find both visible and hidden water intrusion and mold growth problems in the attic, basement, crawl space, and inside and on walls, ceilings, and floors.

One exception is the necessity during the initial inspection to do mold testing of the outward air flow from air supply ducts to help determine whether the HVAC system is mold-infested. Also needed is the physical inspection for mold growth inside the HVAC ducts with a long fiber-optics-cabled video camera inside the ducts with a video display (TV) screen being monitored and recorded by the inspector or hygienist.

Fourth, the five minute-long air mold tests done by most mold inspectors and industrial hygienists is too short to be a good insight into a home or building’s true mold condition. The five minute test takes in 15 cubic liters of air per minute for a total of 75 cubic liters. People live and work in homes and workplaces far longer daily than just five minutes, and they get very sick when exposed to elevated levels of indoor mold!  For information on mold illnesses, visit

Much more insightful is either a half hour or one hour air test, or, better yet, to take physical mold samples from out of the way, rarely-cleaned surfaces that would collect landed or deposited mold spores over a long period of time, such as the top of a ceiling fan, on top of kitchen cabinets, or the top edge of wood trim above doorways and windows.

Fifth, most mold inspectors and industrial hygienists put too much emphasis on comparing indoor mold levels with the mold counts in an outdoor control test. The general interpretation rule is that there is a home or building mold problem if an indoor test documents a higher mold spore count than present for the same species in the outdoor control test.

“Such a simplistic evaluation is over emphasized,” according to mold expert Phillip Fry, who also explains his famous rat theory---“If there are 50 rats running around outside of your home, but only 20 rats living inside your home, is there no indoor rat problem because of fewer indoor rats than the outdoor rat count?”

Another problem in the comparison of indoor and outdoor mold counts is that mold spore levels vary widely and change frequently in a 24 hour day both indoors and outdoors. Mold testing done at four different times throughout 24 hours will result in four significantly different mold counts.

Even modest levels of indoor toxic mold growth can cause severe medical problems for pregnant women, their babies, infants, senior citizens, and persons with lowered body immune defenses, such as persons with HIV, cancer patients, and allergy-suffering people.

Sixth, the capabilities of mold lab personnel and mold lab procedures differ so much that if an inspector or hygienist sends identical mold samples from the same building location to ten different mold labs, he will receive back ten completely different mold lab reports, with some labs not even identifying or mis-identifying or improperly counting commonly-found mold species such as Aspergillus, Penicillium, Cladosporium, and the famous and dangerous Stachybotrys “black mold”.

An experienced and well-trained mold inspector, industrial hygienist, or environmental hygienist learns over time which mold labs are truly proficient and reliable in mold species identification and quantification (mold spore counting).

To arrange for the expert and proficient mold inspection and testing of your home or commercial building anywhere in the United States, Ontario (Canada), or Southeast Asia, contact---

USA and Canada: Phillip Fry, co-manager, EnviroFry, email, phone toll-free 1-866-300-16161-866-300-1616 (USA and Canada) or cell phone 1-480-310-79701-480-310-7970 or visit the website

Southeast Asia: Hank and Merley Taylor, Certified Environmental Hygienists, email, phone (0927) 888-2113 in the Philippines or 63-927-888-2113 for properties located in Hong Kong, Singapore, Malaysia, and Thailand, or visit the website