Mold Problems Began  after radon system installation?

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Concealed Radon System Details

A Concealed, "Moisture Dumb, Wet Air" Radon System Nightmare:

Don't let this fool you. When it is running, this harmless-looking clothes dryer exhaust is really the air intake for a radon system that can deliver between 40 and 100 pounds of water vapor into this condo each day. Air conditioners are almost always overloaded with this much water and they cannot remove it. This excess water vapor just soaks into everything in the condominium in which it was installed until it reaches 70% saturation by weight when suddenly, mold will start to appear everywhere. RadonMan has seen it occur in as little as six months and in other cases it has taken as long as four years. Remember, the air conditioner does not run all the time...but the radon system does and keeps adding water vapor because no one knows to turn it off...and the switch to turn it off is probably unmarked, hidden or inaccessible..

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 This air intake may contain a very small, low capacity air filter that should be washed and replaced every thirty to sixty days. But no one revealed that to the owner or the occupant. If it has no filter, all kinds of bugs including wasps, mud daubers and hornets are sucked in when the system is operating and when the system is off, they are often attracted to this place to build their nests and to raise their families.
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A "Moisture Dumb, Wet Air" radon system causes troubles:

	Does not include sealing of slab penetrations and air handler closet inner drywall liners.
	May use a powerful, single speed blower that runs only at full speed and over ventilates
	May rely on air handler operation to suck in outdoor air when the air handler is operating. This system cannot be turned off except by physically blocking the airflow with a plug or duct tape. The more the air conditioner operates, the more water vapor and hot outdoor air it sucks in. Running the air conditioner can actually increase indoor relative humidity and moisture instead of reducing it
	May be discoverable only by a trained and qualified home inspector or other qualified person
	May create asthma triggers, cause allergies, make occupants sick
	Makes indoor air wet and uncomfortable

In contrast, a  "Moisture Smart, Dry Air" system prevents troubles:

	Automatically keeps indoor air dryer
	Prevents "Bugs, Mold and Rot"
	Reduces asthma and allergy triggers
	Prevents mold
	Keeps occupants dryer, more comfortable and probably healthier
	Reduces electric bill
	Reduces wear and tear on the air conditioner
	Has controls that are obvious and easy to use

A "Moisture Smart" or "Dry Air" system is designed and installed to prevent the Fresh Air Mechanical Ventilation System (Radon System) from raising the indoor relative humidity above 53% most of the time.

What are the Fundamental Features of a "Moisture  Smart, Dry Air" radon mitigation system?

Radon entry into the home is physically blocked by sealing holes in the slab just as water entry into a boat is blocked by sealing the hull and its fittings to make the hull water tight. The most critical radon entry locations to be sealed are the concrete slab penetrations for the air conditioner refrigerant lines and the condensate line AND the inner drywall liner of the air handler closet. This often requires that drywall and sometimes the water heater  be removed to gain access to the slab holes, the openings be cleaned as much as possible, and all openings be carefully sealed using correct, elastomeric sealants, NEVER EXPANDING FOAM as experience has shown that foam seals extremely poorly in this application. Restoring and refinishing the drywall is an additional labor intensive procedure. By blocking off radon entry by 85%, the required ventilation rate can be cut by 85%, thereby reducing the air conditioner's water vapor load and heat load by 85%.  Air conditioners do not like extra moisture loads and extra heat loads so we must add as little extra heat and water vapor as possible to keep indoor relative humidity as low as possible. Mold, bacteria and roaches love high humidity environments of 55% and higher. By careful sealing, much less outdoor air is required for acceptable radon levels. If 100 cubic feet per minute of outdoor air may have been required for acceptable radon levels, when excellent sealing is performed, only 15 cubic feet per minute may be required. Careful, successful sealing does the following: Reduces radon levels Reduces the amount of air, heat and water vapor that must be added to a home and to its air conditioning load Reduces indoor relative humidity Reduces wear and tear on the air conditioner Reduces electric bills Reduces the likelihood of "Bugs, Mold, and Rot." Eliminates the need for a dehumdifiier

In contrast, "Moisture Dumb" radon systems do not include slab sealing because it is slow, painstaking work that requires very careful workmanship and takes much more time. It is much easier, much quicker and much more profitable to leave out the sealing when a mitigator can just add more outdoor air to get acceptable radon levels. No one will know the difference for some time and then it will be too late.

Over ventilation must be avoided. Ventilating to a radon level of less than 3.0 or 2.75 is over ventilating, and it WILL greatly increase risk of "Bugs, Mold and Rot," Reducing the radon level to one-half of its previous level, requires doubling the ventilation rate and doubling the added water vapor and heat. A "Moisture Smart, Dry Air" system uses a variable speed blower that can be precisely adjusted to reduce the radon just right without unnecessarily increasing the heat and moisture load.

The occupant of the apartment in the lower photos has become sick; she advises that she has retained an attorney and intends to file a lawsuit in Lee county to recover for mold damage and disabling illness. She was in good health before she moved into this apartment. This is just one of well over a thousand "Moisture Dumb, Wet Air" concealed radon mitigation system installations in SW Florida. It is not unlikely that there are many more occupants of similar apartments and condos in SW Florida who have also become sick from constant mold exposure.

Mold Count: 44,000 aspergillus/penicillium, about 100 times higher than usually found.

In the upper left corner resides the "innocent" metal clothes dryer hood that serves as the air intake for two concealed radon systems. This is a siamesed system in which one air intake serves two separate apartments. It appears that operation of only one of the two radon systems would result in depressurization of the other to the effect that radon levels may increase in it substantially, The partial vacuum would suck even more radon out of the soil and out of the concrete blocks and dump it right into the breathing zone. Negative pressurization of a home is a big radon NO-NO. Both the radon mitigator and his radon "expert" consultant  should have known better.

These are the indoor clues to the existence of the concealed radon system that dumped large quantities of water vapor into this unit every day. The unmarked access panel is visible in the ceiling. There is a powerful blower and there may also be a concealed table lamp timer to turn the system on and off several times a day. It is not unusual for these timers to jam in the "ON" position causing the radon system to run 24/7. To the left is the switch that is likely the means to turn the radon system on and off. The switch is very high and unreachable without a step stool. It is unmarked.

This radon mitigation system is "Moisture Dumb." Even if the moisture in the home goes very high, the system doesn't know and doesn't care and just keeps on adding more water vapor and heat. This duct delivers about 40 to 100 pounds of water vapor contained in hot, humid outdoor air directly into the air conditioning system each day, and it does it every day this radon system is running. As should be expected, this air conditioner apparently has not been able to remove this extra and unexpected moisture and heat load. Before the extra heat and water vapor were added by the concealed radon system, the air conditioner probably was doing a good job of keeping the home so dry that mold could not grow.

 Were it not for the addition of the "Moisture Dumb" radon system this nightmare for the young woman and for the owners of these apartments would not have occurred. 

(Unfortunately, the owners of this apartment complex may have several hundred more apartments with identical dangerous, defective conditions.)

Result? Day-by-day, for several years, the extra moisture that the air conditioner could not remove soaked into the drywall, the furniture, the carpets, drapes, clothing, shoes. It took quite a while before it reached reached 70% moisture saturation by weight, and serious visible mold infestation began. It is likely that most of the mold began growing on the backside of the drywall in the moist exterior wall cavities long before it could be seen inside the apartment. A condo or apartment can have  a serious mold infestation long before anyone sees any mold inside the home.

The radon mitigation firm that installed this concealed radon system left no labels or marks indicating who they were despite the requirements of Florida radon regulations.

It could easily cost $20,000+ to remediate the mold in this apartment.

All because a "Moisture Dumb" radon system was installed and hidden from everyone.

The woman who occupied this apartment is now very sick.

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Last modified: 06/25/11