During the 2009 CHAMP grant period, Linn County Public Health conducted indoor air quality (IAQ) inspections in the homes of 80 clients, not counting repeat inspections.
During the IAQ inspection, the LCPH inspectors examine the following conditions:
· Type and age of structure
· Material and condition of basement foundation
· Whether home is rented or owned by client (this affects the remedies available to the client)
· Evidence or reports of basement leaks, backups, infiltration, or condensation
· Evidence or reports of visible water damage in other locations
· Storage of materials that may support mold growth in potentially wet or humid areas
· Presence of a foundation crawl space; if present, whether it is sealed and passively or actively vented to outdoors
· Presence of a basement foundation drain sump pit; if present, CO2 concentration at sump and whether sump is properly sealed and vented to outdoors
· Tightness of house – quality of weatherstripping and insulation
· Presence of environmental tobacco smoke
· Type and number of pets and where pets live and sleep
· Number of adults, children, and infants living in home
· Furnace type; presence of combustion air line; if forced air, condition of filter and circulation patterns; if natural draft, presence of backdrafting.
· Water heater type (gas or electric) and vent type (natural or forced draft); if natural draft, presence of backdrafting.
· Stove type and presence and use of vent fan.
· Dryer type and whether dryer exhaust is vented outdoors and vent is working.
· Mold – visual presence or odor, especially in basement, behind furniture, around windows, and where water damage is present
· Presence of appliances such as kerosene space heaters or wood stoves with combustion byproducts
· Chemical storage or use, including cleaning products, in living areas
· Use of fragrances, candles, and incense
· Availability of dehumidifier and air conditioning for humidity control
· Bathroom humidity and whether a fan is available and used
· Housekeeping conditions that could support exposure to dust mites and other allergens
· Reported vacuuming practices
· Carpeting location and condition
· If client uses a carbon monoxide monitor
· Levels of relative humidity, carbon monoxide, carbon dioxide, and temperature at the time of the inspection
· Conditions that support condensation, especially on exterior walls and ceiling and concrete floors (support for mold growth)
· Outside drainage conditions that could lead to water in the home
· Although it is not related to asthma, we install a radon test kit in homes with foundations and educate the client on how to complete the radon test. According to past EPA reports, Iowa has the highest percentage of homes with radon levels over the EPA’s recommended action level of 4.0 pCi/L.
At the end of the inspection, we sit with the client and discuss what conditions we find that may support asthma triggers. We give the client the opportunity to ask questions and discuss possible remedies. In 90 percent of cases, we follow up with a written letter report, which contains contact information if the client wants to follow up.
FINDINGS
The most common asthma triggers in the home environment are commonly mold, dust mites, pets, and environmental tobacco smoke.
Even though CHAMP is a voluntary program and therefore is biased towards families with a high concern for their child’s wellness, smoking occurred in 10 percent of the homes. Thirty-nine percent of families owned furry pets, although the degree to which these pets were managed (grooming, bathing, keeping the pet out of the asthma patient’s bedroom, selection of hypoallergenic breeds) varied. Fifty-nine percent of families reported some mold or musty odors sometimes being present. The inspections did not include any measure of dust mite concentrations, but looked at dust and clutter as a proxy.
Most recommendations related to the need to reduce indoor air pollutants by providing clean air from outdoors. In a normal home, air move out of the home by bathroom and kitchen vent fans, by clothes dryers, by air used for combustion by furnaces and water heaters, and by exfiltration losses of warm air from upper stories. The flow of air out of the home creates a negative pressure, which other air from outside – makeup air – must fill. Makeup air can come though leakage in the building envelope in older buildings, or from gaps and cracks in the foundation. Where an unsealed sump pump pit is present, makeup air can come from gases in the soil around the building. These soil gasses are often high in radon gas and carbon dioxide. In addition to sealing sump pump pits and basement wall cracks, makeup air can be provided from outside simply by opening a window slightly. A more elaborate – and energy efficient – way to provide healthy makeup are is by use of heat recovery ventilation (HRV), which discharges indoor air and brings in outdoor air without losing heat.
The second largest class of recommendations relate to the control and elimination of mold. Sources of moisture such as leaks, shower moisture, and cooking vapor, need to be eliminated or controlled. However, in most cases, the source of moisture (which is necessary for the growth of mold) is condensation. In the summer, condensation comes from warm, moist outside air contacting cool indoor surfaces, especially basement walls. In the winter, condensation comes from moisture from cooking and bathing and human and animal respiration, and may condense on any cool surface, which, in poorly insulated homes during cold weather, may be any wall, or the ceiling or floor.
The third largest class of recommendations related to the control and elimination of dust mites. The growth of dust mites is dependent on a threshold relative humidity, so many of the recommendations for mold control are also effective against dust mites.
The IAQ inspector checks for carbon monoxide (CO), carbon dioxide (CO2), and relative humidity. Carbon monoxide, which not directly related to asthma, is an immediate threat to health and is regulated at the level of 10 ppm. We have never seen carbon monoxide at this level in a CHAMP visit. At any significant elevation above background, CO would be regarded as an indication of poor air quality due to improper combustion, and would usually be associated with other asthma triggers such as particulate matter as a combustion byproduct.
Carbon dioxide is regarded as a proxy for adequate ventilation. The closer the indoor carbon monoxide level is to background (generally 200-300 ppm in spring and 300-400 ppm in other seasons), the better the exchange of indoor and outdoor air – this would normally be associated with lower levels of other indoor air pollutants. CO2 also has been shown, in many specific incidences, to enter the home through the basement footing drain sump. LCPH’s recommendation is to provide ventilation that maintains CO2 below 1000 ppm and preferably below 800 ppm. During the 2008 and 2009 CHAMP program years, 40 percent of homes were found with CO2 readings at or above 1000 ppm. These clients were generally advised on ways of introducing fresh air into their home, excluding the entry of soil gas into their homes, or both.
RECOMMENDATIONS
The 72 letter reports from 2009 and 45 from 2008 were analyzed and up to four recommendations from each were tallied. The recommendations were limited to four from each site, even though in some cases more recommendations were offered. This was done, in part, to weight equally the recommendations of inspectors who offered more recommendations with those of inspectors who tended to offer fewer.
The following table shows the frequency of various recommendations. In five homes, parents were already well aware of good IAQ practices, and we did not feel that any additional recommendations were necessary. For instance, in one case, the family cocker spaniel was shaved and was also regularly vacuumed.
The most common recommendation, listed as “ventilation practices” below, is a broad category that includes a number of specific recommendations, basically to air the house out when possible to prevent accumulation of indoor air pollutants and to reduce condensation in winter. In general this was a primary recommendation where more serious asthma triggers were not present.
The “other” category included things that were unique to the specific house. Examples include attaching a vent to a space heater, installing high-efficiency particle filtration, maintaining negative pressure in a connected garage, and using mold-resistant wall surfaces.
Certain categories of recommendations in the following table were not listed as a top-priority recommendation – these include installing window screens, installing an air conditioner, and using a kitchen vent fan. All of these were recommended at least once, but never as one of the top four priority recommendations.
Of the remaining recommendations, 20 of them – highlighted in the table – relate more-or-less directly to eliminating conditions for mold growth and eliminating mold. Some of these recommendations, such as using a kitchen fan, have other IAQ benefits (in this case, reducing other IAQ pollutants), but taken together, these mold-control-related recommendations make up more than half of the recommendations given. In total, 76 percent of homes inspected as part of CHAMP in 2009 had visible mold or moldy odor.
Note that efforts to control humidity also reduce the growth of dust mites.
Pet-related recommendations are underrepresented because, in general, the families were well aware of the issues involved, were attempting to limit exposure of the patient to the pets, and would have been unwilling to part with a beloved family pet.
Some recommendations are underrepresented in this tabulation because they were given as fifth and later recommendations, which are not tabulated. Smoking-related recommendations are also underreported, as they, too, were reported as fifth (etc.) recommendations to increase the probability that other recommendations would be listened to. The purpose of the letters was to communicate effectively things the client could do to improve the home IAQ environment.
Again, while it is not related to asthma, we test for radon at all CHAMP homes, unless they are upper-floor apartments, trailer houses, or other types of housing that would not be exposed to soil gases (the source of radon.) The median radon level found was 3.9 pCi/L, just less than the EPA-recommended action level of 4.0 pCi/L. In 49 percent of cases, the level was greater than or equal to the recommended action level of 4.0 pCi/L. In our letter reports, we discuss radon results (when they are available), with appropriate recommendations.
POST-PROJECT SURVEY RESULTS
At the time of this writing, 30 of the clients from the 2009 CHAMP program has completed follow-up calls with LCPH. Of these, 100 percent had received one or more in-home visits, 67 percent had received two or more in-home visits, 50 percent had received three or more in-home visits, and 17 percent had received 4 in-home visits.
Six clients (20 percent) had new concerns since starting the program. Eleven (37 percent) wanted an additional visit. 90 percent stated that they had learned about asthma triggers in their homes. 93 percent felt they had learned techniques for improving the air quality in their homes with respect to asthma.
Eighteen of 20 clients who responded to the question, “What changes have you made in response to the recommendations?” had made some change. Of these, six had installed or begun to use dehumidifiers; seven had changed ventilation practices to increase fresh air; four had begun to use ventilation fans in the bath or kitchen; three had installed a radon mitigation system; two had reduced clutter (which encourages dust and dust mites); and others had done the following: moving beds away from exterior walls in winter (to reduce condensation on wall), dusting more, vacuuming more, removing carpet, taking cardboard and fabric storage out of an unfinished basement, repairing a leaky basement, sealing an unsealed sump pit, replacing water-damaged drywall, cleaning away existing mold, and using HEPA filtered vacuum cleaners.
Of the 15 who found one or more recommendations difficult to follow, 10 found recommendations such as installation of heat recovery ventilation too expensive, one could not move beds from the wall because of the room layout, one found opening windows in the winter too unpleasant, one kept forgetting to use vent fans, and one was prevented by property ownership issues from installing a sealed sump pit cover.
25 of the 30 clients said their child knew to talk to an adult if their asthma symptoms became bad; of the remainder one child was too old and four were still too young.
Asked to name one thing they learned in CHAMP, six stated they knew better how to use their inhalers; six mentioned learning how to use a peak flow meter; five mentioned learning how to recognize an attack and respond early; and two mentioned IAQ considerations (sump pit and airborne asthma triggers).
Asked to suggest one thing that would make CHAMP better, one client suggested a refresher visit every year; one suggested having later visits by phone instead of in person; one would have preferred to follow-up call to have come sooner; one wanted more brochures so she could show them to the school; and one client’s son felt that the program should have involved a movie.
Eighteen and one-half stated that their family now had an followed an asthma action plan (one of these volunteered that his family “kind of” followed a plan.)