*At various times in the mold’s growth stages mold will manufacture enzymes which are designed not only to aid in the digestion of whatever cellulose-based food source upon which it is feeding but also to be toxic to other molds which might encroach where a mold colony has established its specific “turf”. In fact, it was the observation of this phenomenon that led to the discovery of the antibiotic “penicillin”, named after the mold species Penicillium which manifested this trait of killing off other competitive fungi. It is during the enzyme emitting phase that the telltale musty or “skanky” smell is usually detected, and it should be noted that it is the airborne enzymes which are most often toxic to people and pets even when the mold itself may not be. <-- back

2.  Surface Sampling One of the valuable reasons for conducting a certified mold inspection is to rule out mold as a problem when it does not exist. Often during the course of a mold inspection it will be discovered that a dwelling or building may manifest discolorations in areas where mold would logically grow. In fact, such considerations may be the reason the client called for the inspection in the first place. Depending upon the need, there are at least two types of surface sampling which can be performed. Surface sampling is typically done either with a swab (which is rubbed on the suspect area and later rubbed onto a growth medium) or an adhesive laboratory tape which lifts and collects material similar to the way that fingerprints are lifted at the scene of a crime. If it is more important to know immediately whether a particular sample is truly mold, a reactive type of test can return results on the spot within a matter of minutes. If it is more beneficial to identify the particular specie/s of mold and other items of interest which can only be revealed under hyper-magnification, a specimen can be collected and sent to an accredited lab for verification and quantification with results being available within several days. This latter test is most beneficial where toxicity issues need to be considered. While there is a modest additional fee for each such sampling and the testing which accompanies it, it can be well worth the peace of mind should the stain or discoloration turn out not to be mold. And, of course, there would be considerable savings for not undertaking any kind of eradication program if it is not actually warranted. Wherever possible, mold inspection is non-destructive and non-invasive. However, it is sometimes necessary to get behind or under surface materials in order to determine the presence or extent of a mold infestation.

3.  Air Sampling Visible inspections and surface samplings are powerful diagnostic tools, but both may fail to reveal mold and neither are effective at detecting problems either out of the line of sight or too small to be seen by the unaided eye. The absence of visible mold does not always mean that there is no mold present. It is not uncommon for there to be high concentrations of mold and mold spores where there is not even an odor to give them away.  The same is true about other toxic substances which may be dangerous though odorless. In fact, some of the most commonly disastrous and hazardous mold infestations occur in unseen areas such as the interiors of wall cavities, basements, crawl spaces, attics, behind cupboards and wallpaper, under eaves, behind water heaters, under sinks, etc., where no mold is in evidence until tremendous damage has been done and/or the environs have been made very ill. To overcome this obstacle, Pro-active Environmental Technologies employs one or more forms of air sampling to reveal the otherwise invisible.

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a.  Active vs. Passive Air Sampling While there are many different types of air samplings which can be performed, there are really only two basic classes of air sampling methods — passive and active. It is important to be familiar with the differences in the technologies, because the results between the two can be significant. (1)  Passive Air Sampling. As the name would suggest, passive air sampling must depend upon whatever is in the air to find and hit the target plate. The best analogy would be to compare it to flypaper which is hung up in an area with the hope that flying insects will somehow land on it. Sometimes it works. But if the air were full of all manner of flying critters, how would one know that any of them happening to land on the sticky paper comprised a truly representative sampling of ALL the bugs present? The flypaper at least uses a component designed to attract insects to it.  The passive collector dish, though coated with a sticky substance, has no way to attract microbes, mold, and other pathogens. If any hit they stick.  If they miss they do not.  Does the collection of "bugs" give an accurate represent ion of what is present in the air?  Who knows?   Virtually all DIY air sampling kits are passive collectors. A passive kit merely exposes to the air, for some period of time (anywhere from fifteen minutes to several hours), a petri dish containing a growing medium. Whatever happens to be floating in the air at the time and finds its way into the dish is then captured onto the sticky surface of the growth medium. When the testing period is over, the dish is capped. Should any viable mold spores or microbials be part of the entrapped particulates, the medium will allow the spores or germs to “hatch” and grow into colonies over the next several days. It is not a bad test for what it does – verify that at least one viable spore or pathogen was present at the time and place of the test and allow for the identification of the colony specie which developed from the spore or microbe. What a passive test does not do is provide enough data to tell whether the presence of mold spores or microbes was a random event or allow for a credible prediction as to the likelihood that other such colonies might be growing in that part of the building’s air space. Nor does it take into consideration the possibility that other species and contaminates might be present in the area which did not make it into the test dish. All such a test would show is that mold spores or other microbials happened to be near the dish and make their way into it the day the dish was exposed. So, while the passive sampler may not tell us all we need to know, we can deduce this. If a passive sampler is used and there is a resultant significant growth of mold and/or bacteria in the sampler dish, there are definitely problems with the indoor air quality where the sample was taken which need to be addressed ASAP.

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(2)  Active Air Sampling. Active air sampling is more like the butterfly net approach, in that sampling is not determined by what flies in of its own accord.  With active sampling a sufficient volume of air is forced to pass over the sticky collection media which will retain whatever was flying in or being carried by the ambient air. When completed, the results are tabulated. By calibrating the volume of air made to pass over the plate for a specific length of time results will represent a fairly accurate sampling of what and how much is in the air space.  All air samples taken by Pro-active Environmental Technologies are of the active class, a far more scientifically accurate means of sampling and verification. Depending upon the kinds of data needed for assessment, there are two kinds of active sampling which can be used, and there are commonalities between them.

				(a)	Both types should be used with at least one sample taken from outside the building to serve as a control in establishing the relative difference between the outdoor and indoor air quality. Depending upon locale, it may be best to have one outdoor sample from each outside elevation of the house as topography, drainage, and landscaping can alter the quality of the ambient air. (For instance, environments with a lot of plant overgrowth around a building may show elevated mold counts, because the amount of shade, retained moisture, and presence of decayed or decaying vegetation will harbor mold.)
				(b)	Both work with a sticky type of collection medium which is bombarded by a measured amount of air forced to it by a specialized air pump.
				(c)	Both work with calibrated amounts of air. Calibrations of the pump’s consistency are made and checked to an outside standard to assure that flow rates across a collection medium happen at a specific force and encompass a set volume of air. This is typically 15 cubic feet of air per minute – “15 CFM” – over a set period of time (usually five minutes), for a total volume of 75 cubic feet of air sampled.
				(d)	Both types of collection devices are sealed and a chain of custody log established when the collection time has elapsed. Then, depending upon the type of results required, the collectors are either observed over time for growth or sent to an accredited lab for processing and analysis.
				(e)	Both are designed to insure that the sampling represents a standardized cross section of the available air in a given air space and not just a random pocket of ambient air and its contaminant load.

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b.  Two Types of Active Air Samplers

In order to know specifics regarding indoor air quality and how to address any negative issues, there are two types of active air samplers.  One is not necessarily better than the other.  Both are important, but both are designed to collect a particular kind of data -- one static and the other dynamic.

(1)

Total Particulates. The first type of air sample employs a specially designed collection cassette with a sticky target plate which will grab and hold whatever is in the air being forced over it.

	Under microscopic magnification, this allows for the enumeration and identification of every little bit, piece, and speck of whatever was in the air that smacked onto the target plate — usually an unsavory mixture of things like mold, mold spores, dust, dust mites, skin cells, pollen, insect parts, pet dander, feathers and feather bits, ash, soot, sand, feces particles, and all manner of other unthinkable things which people are taking into their airways.
	stachybotrys				skin cells	dust mite	pine pollen

				Extrapolations from this test are used to calibrate the overall cleanliness of the air known as total particulate count. It is very helpful in comparing indoor air quality with that of the outdoors.
			(2)	Viable Colony Count. The second type of air sample is similar to the passive sampler, in that it also uses a petri dish containing a growth medium. But in the active instance, the flow of air is calculated and precise and therefore provides accurate representation of the overall quality of air as it relates to the presence of mold spores and microbials capable of creating a problem.
				Depending upon the purpose of the test, once the collection is made, one of two protocols is followed. If relative comparisons alone is the aim  in order to establish before and  after conditions related to air treatment, all samples are observed and photographed at specific timed intervals such as 24, 48, 72, 96, 120 hours, etc.  Because some species of mold and other contaminates are slower growing than others, this allows for tracking the viability, virulence, growth rate, and varieties contained within the samplings. Where there may be litigation involved and more specific information is required, all the test samples are kept below a certain temperature until they reach an accredited lab so that the number of colonies any mold spores or microbes incubate can be timed and quantified.

The results are identified by specie and measured in CFU’s or “Colony Forming Units”, a number which indicates the level of mold infestation or microbial danger and helps project what the potentials for a disastrous infestation would be if conditions allowed for maximum outbreak of mold or pathogens based upon numbers of spores/microbes present. It also is an indicator of the relative related health risks to the environs in a building.

Variations of both of these active types of devices can be used to sample specific areas of carpets or drapes and even collect samples from inside wall cavities with minimal invasion or damage to the plaster or drywall. When either the content or the volume of the contaminants within the specimens exceeds what is known to be safe, effective corrective measures can be taken. Before and after samplings can be used to compare the efficacies of any mold or microbial eradication regimens undertaken. As one would expect, there are additional costs for each sample and lab analysis performed. Use of air sampling puts to the lie the misconception in our popular culture that mold and microbials only grow in dim and unkempt areas of buildings and in the homes of the less advantaged. To the contrary, properly conducted air sampling has repeatedly proven that many upscale buildings and residences routinely fall prey to both types of infestations – even where housekeeping is almost religiously immaculate. It is the one definitive way to find out if mold or pathogenic infestations do or do not exist in an occupied environment.

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4.  Minimally Invasive Boroscope® Inspection

In the past, just looking for mold or microbials could be an expensive and dangerous proposition. Because either -- and especially mold -- can lurk in so many hard to reach places, conventional practice was to observe or suspect a problem in a building and, beginning there, to start smashing drywall (politely called “demolition work”) to see to what extent it had spread. It would be similar to asking a doctor to find and diagnose an internal illness when his only tool was a scalpel or bone saw. The problem is exacerbated when the hammer blows or saw cuts actually strike near a mold colony and scatter billions of eager spores or other contaminates throughout the living space. Fortunately, Pro-active Environmental Technologies employs instrumentation which makes use of fiber optics in peering behind and into places otherwise inaccessible to determine the presence of a mold intrusion. Any penetrations in the “skin” of a wall, whether interior or exterior, to allow observation within a wall’s cavities can be done with judicious precision, allowing for minimally invasive inspection of a structure. It is also helpful in examining behind large pieces of furniture — where mold might have taken root up against a wall or another surface — without having to hire movers to allow the inspection to take place. Fiber optics allow the inspector to examine the walls and cabinets behind and under sinks, track feeder plumbing behind walls, inspect behind water heaters, and look in all the places moisture likes to intrude and collect which do not always present themselves to the unaided eye.

 

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5.  Moisture Detection Temperature and relative humidity differentials are valuable clues when trying to pinpoint a suspected problem such as mold which may not be readily visible. Pro-active Environmental Technologies makes use of non-destructive moisture detectors and infrared temperature and relative humidity devices to aid in finding hidden areas where mold may be growing or in tracking a water intrusion to its source. These instruments allow the inspector to find moisture behind walls and baseboards, in saturated construction members, and even in large amounts of insulation — anywhere that water or elevated moisture can be a breeding ground for destructive and deadly species of mold or other pathogens. They can also indicate where air conditioning ducts are leaking, causing cold spots on the interiors of walls which then condense moisture and harbor mold. While mold sanitization can penetrate wall cavities and kill mold in such places even if undetected, it is the presence of moisture which must be found and corrected in order to keep the mold from coming back. Therefore, the Pro-active Environmental Technologies inspector will use all the tools available to find the mold’s source and underlying cause/s so that the present problem can be corrected and future ones avoided.