RENTERS BEWARE: APARTMENT HVAC CLOSETS CAN BE SOURCES OF MOLD AND DEGRADED IAQ

Furnace on water damaged OSB platform.  The return plenum is located beneath the platform.

Furnace on water damaged OSB platform. The return plenum is located beneath the platform.

A common practice in multi-story apartment and condominium complexes is to house the furnaces in closets that are located on the patio or balcony for each unit. The closets are aligned vertically in each building. Although the orientation is convenient for plumbing access, numerous water damage issues are inherent to this type of HVAC set-up.
Water damage from plugged condensate drain tubes or malfunctioning condensate drain pans is common. Slimy biological growth in PVC tubing and drain pans pan causes overflows. Current or historical overflows from the pans will appear on the sheet metal plenum under the A-coil. Drips and mold growth from malfunctioning units above a closet are commonly apparent as drip stains or growth on the ceiling and walls of the closet.
Water damage caused by freezing and thawing of the AC coils is common in apartment HVAC systems. Filter changes are often left in the hands of uninformed tenants. Plugged filters prevent sufficient air flow to the coil, causing it to freeze. As the coil warms up, the ice thaws, releasing large amounts of water into the return plenum, floor system of the apartment, furnace platform, or furnace closet below the damaged unit.
Another issue associated with stacked HVAC closets is the installation of the furnace on a platform, which is commonly constructed from plywood, drywall, or oriented strand board. When wet, all of these materials support the growth of mold and bacteria, which can produce various toxins. Additionally, the glues and resins in these materials can be liberated when wet.

Ceiling of furnace closet showing water entered from HVAC  closet above.

Ceiling of furnace closet showing water entered from HVAC closet above.

The return plenum in furnace closet systems is located beneath the platform, with the underside of the platform being the top of the plenum, a concrete slab serving as the bottom, and the walls of the platform forming the sides of the plenum. In addition to being difficult to clean, a water damaged common plenum provides both a contaminant source and transport pathway.  Dust mites, insects and their fecal material, garbage, cigarette butts, contaminated chunks of paper, and rodent feces are just a few of the treasures that have been recovered from plenums under furnace platforms.
When damage does occur, the underlying cause of water must be corrected. This involves replacing plugged drain tubing, cleaning drip pans, cleaning coils, and changing filters. For consistency, preventive measures in the form of routine inspections and HVAC maintenance should be the responsibility of the management company or maintenance staff.
Addressing the consequences of the water damage, whether it manifests as biological growth or deteriorated building materials, is imperative to appropriate HVAC hygiene and good indoor air quality. Contaminants on water damaged plywood, OSB, and drywall in the furnace closet and on the furnace platform can cause adverse health effects, whether the growth is active or historical. Once dried, mold and bacteria engage in survival mechanisms that can include toxin production and increased sporulation. When dry, the contaminants are easily liberated into the airstream.  Mold remediation is required when building materials in furnace closets become contaminated. The remediation involves two components (1) removal of the mold or contaminated building material and (2) addressing spores that are released from areas of actual growth. Engineering controls, containment barriers, HEPA filtered air filtration devices, personal protective equipment, HEPA vacuuming, and damp-wiping are all essential for safe and effective remediation in water damaged furnace closets.

Return grille located inside of the apartment behind the furnace platform.  Stains show repeated wetting fo tack strip.

Return grille located inside of the apartment behind the furnace platform. Stains show repeated wetting fo tack strip.

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MOLD CLEAN-UP AFTER A HURRICANE IS NOT A DIY PROJECT

Hidden mold on underside of sub-floor after a flood

Hidden mold on underside of sub-floor after a flood

http://www.thedoctorstv.com/videolib/init/8286_

The above link provides some good information on the hazards that are inherent to flooded buildings. Good information in the clip includes:
• Chemicals, such as pesticides, gasoline, hydrocarbons, rotted food, and other harmful agents can be transported indoors with flood waters.

• Animal fecal material, carcasses and pathogens are inherent to flood waters.

• Fungi (mold) grow indoors on drywall, wood, and other cellulose contents.

• Mold that grows indoors can make people sick.

• Moldy drywall must be discarded.

The overall message that water damage to buildings is unhealthy was very clear in the news clip. However, due to the shortness of the clip, information was limited. The public should be aware of that many hazards exist after floods. As reported by the World Health Organization (Dampness and Mould, 2009), other harmful agents in water damaged buildings include bacteria, endotoxins and exotoxins from bacteria, mycotoxins from mold, chemicals released from wet building materials, insects, and other contaminants that can be transported indoors with surface and ground water.

The media clip does fall short relative to its discussion about clean-up. The recommendations from the interviewed mold expert do not emphasize that flood clean-up is not a do-it-yourself project. Although the reporter and expert donned protective gear prior to entering a flooded house, the importance of hazard training and medical clearance for using personal protective equipment is not addressed. This could turn into a situation where a little knowledge could be dangerous.

The issue of restoring wood after a flood was misrepresented in the clip. The expert suggested that unless wood was rotted, abrasive cleaning would effectively restore mold contaminated wood after a flood. This is information is not correct. Wood that has been in contact with the flood water is contaminated with the same chemical and biological agents as the drywall that the expert states must be removed. Abrasively cleaning of wood will only address the outer accessible surfaces. Wood has six sides. Ignoring the surfaces that cannot be accessed for cleaning (interface between bottom plates and flooring, stacked studs, etc.) are typically the most contaminated because they remain wet for the longest periods.

The surfaces with trapped contaminants can cause exposure hazards long after restoration and re-build are complete. Contaminants that remain on wood in floor, ceiling, and wall cavities can be liberated with pressure differentials, physical disturbances, and normal living activities. Since people can react to dead mold and other contaminants that remain after a flood, failure to address the “hidden” surfaces could be quite dangerous, especially to people to young children, elderly people, asthmatics, or those that are immune-compromised. Appropriate remediation scopes for damages from catastrophic water losses, such as those caused by Hurricane Sandy, are paramount to preventing future indoor air quality problems.

MOLD TEST KITS: Why You Should Not Do-It-Yourself

Using a “do-it-yourself” (DIY) mold test kit to evaluate whether a home has a mold problem makes about as much sense as replacing an annual doctor exam with using a thermometer to take your temperature.  Just as a person could be very ill while maintaining a normal temperature, a home could have a serious mold problem, even though a DIY test was negative.

Designing, executing, and understanding a comprehensive indoor mold assessment is difficult enough for professional mold consultants.  The best ones understand that building dynamics, hidden mold, historical damage, sampling techniques, analytical methods, and many other factors can influence the accuracy and effectiveness of diagnosing indoor mold problems.

Unlike chemical testing, no dose response curves have been developed for mold exposure.  Therefore, sample results will often raise more questions than answers.  Mold spores are always present in indoor environments. They enter buildings through doors and windows, and usually are not a problem unless they have suitable nutrients for growth.  All building materials can support mold growth IF sufficient moisture is present.  Moisture can come from leaks, floods, or excess humidity.

When sufficient moisture is present, certain molds that are usually minor constituents of outdoor air grow disproportionately to predominant outdoor molds that grow on decayed vegetation.  The molds that grow indoors on wet drywall, wood, and other cellulose materials are most frequently in the genera, Aspergillus, Penicillium, Stachybotrys, and Chaetomium.  These molds can present health problems when they grow indoors.  In addition to allergic reactions, triggering of asthma, and infections, many molds that grow indoors produce secondary metabolites, such as toxins.   The tightness of indoor environments can promote exposures and adverse health to occupants of water damaged buildings.

The single best tool in a mold assessment, whether it is performed by a professional or a do-it-yourselfer, is a detailed visual inspection.  The simplest inspection involves observations of mold growth after a water damage event.  If you see it, yes it is there, and must be addressed to prevent air quality problems.  More involved inspection that require professionals are those in which prior unmitigated water damage has been concealed or construction defects result in hidden water damage in ceiling, wall, or floor cavities.

For the do-it-yourself mold tester, the best that can be expected from a home test kit is to identify the type of mold is visibly growing on a surface.  However, if it is growing, the source of moisture must be corrected and the mold must be removed under controlled conditions.  Since remediation procedures are not dictated by the type of, testing is usually a waste of money.  If the area of growth is small and a low likelihood exists for hidden mold, addressing the mold according to EPA guidelines found in A Brief Guide to Moisture, Mold and Your Home (epa.gov) is sufficient.  If the mold covers a large area or hidden mold is suspected, a professional remediator is usually required to avoid hazardous exposures and cross-contamination to unaffected areas.

The worst outcome from a do-it-yourself mold test kit is that negative results will give a false sense of security when in fact hidden mold problems do exist.   False negative are common in culture plate kits (petri dishes) that instruct the user to place the open plate in a room for a specified period of time to collect mold that settles from the air.  The lab reports for settling plates might list several types of mold that grew the petri dish.  However, the data is usually inconclusive at best.  One problem with “settling plate” is that all molds do not settle at the ratio in which they are found in the air.  Therefore, many species can go undetected.  Another issue is that the actual concentrations of mold spores per volume of air cannot be calculated because the sampling method cannot quantify the amount of air to which the culture plate is exposed.  Additionally, the methodology does not address whether the molds entered from outdoors or were from areas of actual indoor mold sources.

Another type of test that might be recommended for the culture plates is to tape the open culture plate to a supply register to allow the air from an operating HVAC system to impact the plate for a specified time.  Unfortunately air exiting from the airducts does not necessarily represent air within the home because the air that passes through a filter before impacting the culture plate.  Additionally, the likelihood that contaminants would actually be released from an area of growth, enter the air stream, be sucked into the return ducts, pass through the filter, and ultimately end up on the culture plate is very low. 

Swab type test kits are commonly available for DIYers.  Directions generally instruct the user to wipe the swab over a small area (usually 1 sq. inch) of suspect mold growth.   The resultant lab report might list several molds that were found in the swab sample, but this method cannot differentiate between settled spores and what might have actually been growing on the surface.   In either case, the results should not be mistaken to represent the moldiness of the whole house.

Still another type of surface sample that can be found in home mold test kits is a tape lift sample, which involves using clear cellophane tape to “lift” suspect mold from a surface.  This type of sample can be useful in identifying not only the type of mold that is present on a surface, but can also differentiate between actual mold growth and spores that settled from the air.   But the sample would be representative of the tested area only and would not provide information on the overall mold conditions in the indoor environment.

Mold testing can be a useful tool in the hands of a knowledgeable investigator that designs a sampling plan to address a question that cannot otherwise be answered.  Unfortunately, even within the mold assessment and remediation industries, few investigators understand the principles of microbiology, building science, engineering, and scientific methods that are required to conduct a meaningful mold investigation.  With so many variables and limitations in mold testing and analytical methods, “do-it-yourself” mold test kits are generally a waste of time and money.

Featured In October Women’s Health: “Beat Bad Air Days”

Women's Health | October 2010

Women's Health | October 2010

Extra! Extra! Read all about it! It’s finally on news stands! We’re featured in the October issue of Women’s Health Magazine. The article, “Beat Bad Air Days”  begins on page 76. The article covers indoor air quality and I have the last word which can be found on page 79.

Connie Morbach To Be Featured In October “Women’s Health” Magazine!

Women's Health | July/August CoverI’m elated to announce I will be featured in the October issue of the nationally published “Women’s Health” magazine. I had the opportunity to speak with Women’s Health writer Kate Bowers giving my views on the importance of indoor air quality: what are the risks of household pollutants and what can people do to improve indoor air quality and more.

I’m excited to declare the CleanliNEST™ Crusade is picking up national steam. Here’s to everyone breathing easier!

Take a moment to check out the free iPhone and iPod Workout App from Women’s Health at the link below. Nice workout tool at an even nicer price!

Click here for the Women’s Health Workout Lite App

From Our Video Archives: Sanit-Air Featured On PBS “The Business Page” Television Program

The nationally recognized Public Broadcasting System affiliate in Detroit, WTVS Channel 56, produced and aired a wonderful local business program titled “The Business Page.” Sanit-Air and our team of environmental IAQ experts and technicians had the distinct pleasure of an extensive feature on “The Business Page.”

Producer Mike Echols narrates this business feature that serves as a nice introduction to the basic understanding of the workings of Sanit-Air and the foundation for our CleaniNEST™ brand and consumer crusade. We hope you find “The Business Page” feature on Sanit-Air informative.

Raising the Bar Promotes Peace of Mind for Remediation Contractors and Homeowners

While attending a certification course for EPA’s new Renovation, Repair, and Painting (RRP) Rule, I tried to empathize with contractors that were outraged that the government would “force them out of business” due to the increased costs associated with requirements for notification, certifications, documentation, and environmental controls that would be mandatory with the RRP, which was enacted April 22, 2010 .  Understandably, the new lead law, which applies to all residential jobs in homes built prior to 1978, raises concerns that certified contractors could not compete with the bids from the “chuck and a truck” one-man contractors that operate under the radar of building inspectors and state regulators.   However, based on the devastating and permanent damage that lead exposure can have on small children and unborn infants, I would have felt much better about the restoration industry if the expressed fears dealt more with being concerned about causing harm.

I am not fully confident that governmental agencies should be regulating professional standards of care.  Over the last ten years, the uninformed attempts that many state governments have made to set standards for mold exposures convinced me that politicians should not be allowed to “spin” scientific data for the purpose of getting votes.    However, if as professionals, we cannot police our industry, some governmental intervention is necessary to raise awareness and protect the public.

I admit that numerous creative suggestions regarding avoidance of the RRP Rule arose during the class.  One contractor suggested that the demolition part of a job for a home built before 1978 would be performed at no costs, while the re-build portion of the proposal would be elevated to cover the “free” demolition.  This would supposedly eliminate the need to comply with the lead rule because the law applies to work performed “for compensation. “   Another attendee suggested that we should ban together as an industry and protest to Washington about too much governmental intervention.   Too bad the same effort was not spent on trying to figure out how to expedite “doing the right thing”.

The bottom line regarding lead or any other hazards that might be present in the homes where contractors perform any type of repair, renovation, restoration, or remediation is that we have a professional obligation “to do no harm.”    Ethically, this mantra should be part of every contractor’s written or implied mission statement.  It is in fact, the number one cannon in the Code of Ethics for most professional indoor air quality associations, including the Indoor Air Quality Organization and American Industrial Hygiene Association.

Doing the right thing provides peace of mind, which is priceless.

Additional Information at

www.epa.gov/lead

www.cdc.gov/nceh/lead/tips.

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