What should you think about when buying an air cleaner?
Eliminating sources, for example tobacco smoke, and ventilation are the most effective ways to eliminate most indoor air problems. However, in cases where these choices aren’t appropriate an air cleaner may be an attractive alternative. When selecting an air cleaner it is important to determine what types of particulars are of most concern to you and find an air cleaner with a high efficiency rating at removing this type of particle. The effectiveness of an air cleaner depends not only on efficiency in removing particles but on the volume of air it cleans. For portable units this information should be available as its treatment volume expressed in cubic feet per minute(CFM). Some table top models process so little air that even though they have very efficient filters they are not very effective at cleaning the air in a room. The CADR or clean air delivery rate is an attempt to combine these two. For portable air cleaners, the discharge pattern of cleaned air can be important. Some discharge air in one direction which could be helpful for a person seated or sleeping. However, devices which distribute air in many directions will usually be more effective at providing clean air to an entire room. The American Lung Association report “Residential Air Cleaning Devices: Types, Effectiveness and Health Impact” provides a detailed description of various types of air cleaners and reviews available evidence on their effectiveness.
How do I determine that I have an indoor air quality problem in my home?
Air quality problems can be difficult to identify, isolate, and correct. Many problems seem to start after homes are closed up for the heating season. You have a problem if your smoke detector sounds with little or no seeming reason or if your carbon monoxide detector sounds an alarm. Besides the gases that set off these two alarms, tests can easily be conducted for radon. Monitoring the health of your family is another way of identifying air quality problems. While the symptoms of many pollutants are the same as for flu and some other illness, when several family members suffer from similar symptoms and do not respond well to treatment, it could be something in the household environment. If you or some family member seems to feel better after some hours out of the home than after a few hours in the home, that is an indication that something in the home may be causing the symptoms. Also, if family members seem to need a lot of sleep and don’t wake up rested, it could be the air quality. Medical attention is recommended for any of these types of symptoms, and be sure to bring to the doctor’s attention the possible link to the home environment.
What should I do if I suspect an indoor air quality problem?
Reduce your exposure to the potential problem and consult your doctor for a diagnosis. Reducing exposure may mean spending more time out of the home which can be difficult if you do not feel well. Consider visiting friends, family, or neighbors. If vacating the home is not an option, then increase the ventilation to reduce the concentration of the pollutant / toxin in the air. Get help with identifying the source of the problem. Advice from your doctor, local health department, or others will help you understand what steps need to be taken to remove or neutralize the source of the pollution / toxin. Finally, take the recommended steps and conduct tests to verify that conditions have changed.
- American Lung Association
- Consumer Product Safety Commission Publications
Consumer Product Safety Commission Phone: 1-800-638-2772
- EPA – United States Environmental Protection Agency Indoor Air Quality
- EPA – United States Environmental Protection Agency home
- University of Montana – Indoor Air Quality
Can conditons in the home trigger asthma attacks?
Many of the triggers for asthma are most prevalent indoors. Here are some common home related triggers.1. Secondhand Tobacco Smoke – Smoke from the burning end of a cigarette, pipe or cigar as well as the smoke breathed out by smokers is a major trigger of asthma attacks. At a minimum don’t allow smoking inside your home or cars.2. Wood smoke – Smoke from fireplaces and wood stoves is another irritant associated with Asthma. Make sure wood burning appliances are in good working order with clean leak free stove pipes. Burn in a way that minimizes smoke production.3. Dust mites – These are organisms, too small to see, that live on the skin we slough off among other things. Frequent cleaning of bedding including pillows in temperatures of at least 130 degrees Fahrenheit is one important step in controlling dust mites. For asthma sufferers, removing carpeting and drapes from the bedroom and enclosing the mattress in a plastic case can help. Controlling relative humidity is also important.4. Molds and other fungus – Spores and gases given off by various funguses growing on surfaces in the house are common triggers. To prevent mold growth keep relative humidity low. In the winter the relative humidity should be about 35%.
Attic Insulation & Asbestos
Is vermiculite insulation an asbestos hazard?
Insulation made of vermiculite and sold under the brand name Zonolite is a possible asbestos hazard. Zonolite was a do-it-yourself product for attic insulation marketed until the mid 1980s. It was not widely used. Samples of vermiculite taken from its Montana source have asbestos levels considered hazardous. Whether the insulation is hazardous is still being determined. Vermiculite insulation is easily distinguished from the much more common types of loose fill insulations – cellulose, fiberglass and rock wool. All of these common insulation types are fibrous. In contrast, vermiculite is in the form of brownish silver accordion-shaped chips. If you suspect you have Zonolite in your home the U.S. Environmental Protection Agency (EPA) recommends you leave it alone and be alert for information from the EPA about whether it actually constitutes a hazard.
How do I find a Carbon Monoxide alarm that doesn’t have lots of false alarms?
Several years ago Underwriters Laboratory (UL) changed the standards for carbon monoxide alarms. To avoid the problem of false alarms, the revised standard UL 2034-98 requires that alarms ignore levels of CO below 70 ppm. The alarm must now sound if a CO level of 70 parts per million (ppm) is reached and remains for at least three hours. If higher levels are reached, it must sound more quickly but still not instantly. This prevents a sudden brief spike of CO or another gas from triggering the alarm. Detailed instructions and a reset button must be provided to allow testing the alarm.
How do I know if my CO detector has given a false alarm?
Recent work at Iowa State University and by some utilities have demonstrated there are few, if any, “false alarms” from the detectors. If the detector goes off, follow the instructions provided with the detector. Always follow up to determine what conditions caused the alarm to sound. Episodes of carbon monoxide production in a home can be intermittent and hard to detect. Some causes may be easier to identify than others. Blocked chimneys, chimneys that don’t draw properly, and breaks in flue pipes between chimney and furnace may be relatively easy to detect.In homes with attached garages the car may be the source. When a cold auto engine first starts, it produces a large amount of carbon monoxide. The deadly fumes from an engine can build up quickly in a garage, even with the door open. Because many houses with attached garages get a big portion of their air through the garage, the carbon monoxide from the car gets pulled into the house. It can take hours before the CO levels in the house get high enough to trigger the alarm. This delay makes it difficult to pinpoint the source of the CO.
What is Carbon Monoxide (CO)?
Carbon Monoxide (CO) is a colorless, odorless, and tasteless gas. Usually only produced during burning of carbon based fuels when combustion is incomplete, or when not enough oxygen is supplied to the burning process. Probably the best known source of CO is from automobile exhaust. Carbon monoxide causes more poisoning deaths today than any other substance. A carbon monoxide detector is the only reliable way to detect the presence of this colorless, odorless gas.When inhaled, carbon monoxide bonds with the hemoglobin in blood, displacing oxygen and resulting in oxygen starvation within the body. The brain and heart require large amounts of oxygen and quickly suffer from the oxygen shortage. This makes even small amounts of carbon monoxide dangerous.The symptoms of carbon monoxide poisoning can mimic the flu, including headaches, fatigue, nausea, dizziness, confusion and irritability. Continued exposure can lead to vomiting, loss of consciousness, brain damage, muscle weakness and death. Because the symptoms resemble many other illnesses, carbon monoxide poisoning can be hard to identify.
Dangers of Secondhand Tabacco Smoke
How much of a danger is tobacco smoke to non smokers?
One of the greatest concerns is the connection of second hand smoke to Asthma. Asthma is now the leading chronic disease among children. Between 1980-1994, asthma among young children increased by 160%. Nearly 1 in 13 school age children has asthma according to the Association of State and Territorial Health Officials.Second hand smoke is also associated with several other health problems in children. Over 150,000 respiratory infections per year in toddlers are linked to second hand smoke as well as nearly a million middle ear infections. Even Sudden Infant Death Syndrome has been linked to second hand smoke.For adults the most serious problem associated with second smoke is lung cancer. The U.S. Environmental Protection Agency (EPA) has concluded that second hand smoke is a significant cause of lung cancer in non smoking adults. While its ability to official classify second hand tobacco smoke as a carcinogen has been held up in the courts, the EPA maintains that the science behind the link to cancer is not at issue.
Are the sanitizers heating duct cleaners use safe?
According to the U.S. Environmental Protection Agency few santizers are tested for use in duct work so possible health problems haven’t been studied. Furthermore, there is no system for reporting health problems from sanitizers so the extent of the problem is uncertain. However, there have been reports of burning eyes, headaches, itchy skin, nausea or sore throats.It is also not clear whether these antimicrobial agents are effective in duct work. In a layer of dirt with embedded microbes, if the agent is sprayed on the surface will it kill the mold or other problem microbes if it doesn’t make contact? Will the agent actually reach all the areas where the microbes are living? What is the effect of the frequent movement of air through the system on effectiveness? If the agent does kill mold, for instance, will the casings, which are still an allergen be released into the air in the duct and find their way into the home?Because of these and related questions the EPA recommends against applying disinfectants and sanitizers not be applied in heating and duct systems unless the product is registered for this use and includes specific directions for use in heating and ventilation systems.
Is duct cleaning really needed?
Routine duct cleaning is not usually necessary. The U.S. Environmental Protection Agency (EPA) suggests that if a household member is experiencing respiratory problems or other symptoms that are unexplained and grow worse when the person is in the home, duct cleaning may be in order. According to the EPA, there is no evidence that duct cleaning prevents health problems or reduces the dust levels in the home. In fact, improper cleaning may create problems. If you do decide to have your duct work cleaned, interview several service providers. Ask for references, and ask if they follow the duct cleaning standards issued by the National Air Duct Cleaners Association (NADCA). Avoid providers that make sweeping health claim or recommend annual cleaning.
How dangerous are the electromagnetic fields around appliances?
Electric fields are invisible lines of force that surround any electrical device. These fields don’t directly transfer energy, so for many years they were ignored as a health concern. There have been a number of studies that suggested health links to cancer, specifically leukemia. However, a report from the National Institute of Health Sciences reviewing all the research on the subject concluded that the association between leukemia and EMF around power sources is weak. It found even less reason to be concerned about other possible health effects. While the report concludes that the association with health effects is weak, it does not conclude that concerns about the health effects of EMF exposure can be entirely dismissed. It suggests continued education aimed at reducing exposure, both by the public and by utility workers. The primary way to limit exposure to EMFs is to stand back from appliances when they are in use and to turn them off when they are not in use. Exposure to magnetic fields drops dramatically with distance from the source.
Fiber Glass Insulation
I have heard that I should avoid fiber glass insulation because it is health hazard. Is this true?
There have been allegations that glass fibers can cause cancer. The argument is that its fibers are close relatives of asbestos and can become imbedded in the lungs just as asbestos fibers can. However, Wisconsin Department of Health officials point out that fiberglass fibers are larger and they are soluble. These characteristics make it less likely that they will bypass the respiratory defense system and then become embedded in lung tissue.
A respected international group, the International Agency for Research on Cancer, recently reviewed the research related to cancer and fiberglass and concluded that fiberglass insulation could not be classified as a human carcinogen. For further information on this study, visit North American Insulation Manufacturers Association. Nevertheless, fiberglass is an irritant to the respiratory system and to the skin. This is mainly a concern to workers who must handle the material. Anyone handling fiberglass should wear gloves, long sleeves and a dust mask to minimize contact with the insulation.
Does freon leaking from a central air conditioner cause health problems?
According to a toxicologist at the Wisconsin Bureau of Public Health this type of freon exposure is not likely to cause any long term effects. Headaches or dizziness during the time you were inhaling it might be possible but symptoms would disappear when the exposure stops.
Fresh Air Intake for Ventilation
Is adding a fresh air intake to a furnace duct system a good way to get additional ventilation?
Many new homes are tight enough that natural air leakage does not provide an adequate supply of fresh air. An inexpensive way to provide additional fresh air is to use the existing duct system and blower from a forced air furnace. There are some problems that need to be considered in designing a system to do this.
- the typical furnace blower moves a lot of air and uses a lot of electricity. If the blower is used for ventilation when the furnace is not operating the blower may create uncomfortable, cool drafts.
- the system can be an energy waster if an ordinary flapper damper is used. Outside air will be added whenever the furnace operates regardless of whether ventilation is needed.
- in cold climates the air being introduced could be so cold that it could cause a thermal shock to the furnace heat exchanger if the air source is too close to the furnace.
- the system may create a positive pressure in the home. If there is no exhaust system operating air may be forced into walls. This in turn can lead to condensation in walls.
Furnace Filters and Allergies
Are there furnace filters that can effectively remove allergy-causing dust?
The answer to your question is not simple. It depends on what causes particular allergies. Air born allergens vary in size and different types of air cleaners are effective for different size and types of allergens. A recent study published in the ASHRAE Journal compared the effectiveness of three popular types of filter systems in removing cigarette smoke from the air. The first is known as an electrostatic filter which looks similar to a conventional furnace filter but uses an electrically charged mesh to remove dust. These seem to vary considerably in their effectiveness. Those tested in the study were not very effective. Electronic filters also use the idea of electrically charging particles. However, they use electricity to maintain opposite charges on two plates. Particles first pass a plate that gives them a charge. Another plate downstream which is oppositely charged attracts or precipitates out the particles. The third type is a High Efficiency Particulate Arrestor(HEPA) filter. This is a very fine filter material that is particularly effective at removing small particle. Both the electronic and HEPA filters were very effective in removing cigarette smoke. The initial installed cost was similar for both systems, however, the HEPA filters need to be replaced while the Electronic filters have a long life if cleaned regularly. On the other hand, the HEPA filters do not require electricity while the electronic filters use electricity – $20 to $30 per year at local electricity prices.
Gas Appliances and Venting
What determines whether gas appliances need to be vented?
Gas refrigerators typically require venting to the outside. To find out if your refrigerator should be vented, read your owner’s manual. If you don’t have an owner’s manual, contact your dealer for the address of the manufacturer and seek its recommendation. Gas hot water heaters and gas fired refrigerators need to be vented because they cycle on and off throughout the day. This means they are likely to produce more combustion products than a kitchen range that is used only a few hours a day and is usually closely monitored. There have been proposals for several years to require that gas cooking appliances be vented, especially in new, air-tight houses.
How do I know if there is lead paint in my house?
Lead was banned from coatings used in homes in 1978. Paint already in customer’s hands may have been used on houses for a year or two after that. So houses built after 1980 are unlikely to contain hazardous paint or varnish. Homes built before that time are likely to have lead-based finishes on some surfaces. Houses built prior to 1940 almost certainly have lead-based paint on some surfaces. The hazardous paint is likely to be both on the inside and the outside. On the inside, it is most likely to be on baseboards, door and window trim and on the windows and doors themselves. It is much less likely to be on the walls. On the outside it may be on the trim, windows and doors but also on the walls. For information about lead testing, visit the web site of the Lead and Asbestos Section of the State Department of Health and Family Services at Lead Safe Wisconsinor phone 608-261-6876.
What do I do if there is lead paint in my home?
Lead-based paint that is in good condition isn’t an immediate hazard. It becomes a hazard when it deteriorates. At one time the concern was limited to paint that was flaking or chipping off. Pubic health experts now know that dust containing lead is also a problem. The dust can be created when two surfaces rub together, for example, a window moving as it is opened or closed. It can also be created as paint ages and its surface turns chalky.If you discover lead-based paint there are some temporary and some permanent solutions. Washing surfaces every other week with a cleaner recommended for use with lead-based paint, using a vacuum with a high efficiency filter known as a HEPA filter and painting over surfaces are all good short-term steps. A good paint job will protect the surface for four to ten years.There are two permanent solutions to lead paint hazards: either remove them or cover them permanently. For example, cover exterior walls with new siding or interior walls with new wallboard. If you choose the removal route, consider hiring professional who have special training and equipment. For the names of contractors who are certified to work on lead-based paint hazards. For information about dealing with lead hazards, visit the web site of the Lead and Asbestos Section of the State Department of Health and Family Services at Lead Safe Wisconsin or phone 608-261-6876.
Why is there so much concern about lead in older homes?
Lead poisoning is a common problem among young children. It is particularly a problem for very young children because their bodies more readily absorb lead and it can produce permanent affects on their nervous systems including retardation. Lead finishes on household surfaces is currently the leading source of lead poisoning in children.
Lingering Smoke in Fireplace
Why would there be a smoke smell coming from a fireplace days after the last fire?
The most likely source of the smell is outside air being drawn down the chimney. As it passes through the chimney and fire box it picks up some of the smokey odor. Air is more likely to be drawn down the chimney if some other appliance is exhausting air. For example, a conventional furnace pulls air from the house to feed combustion. If the house is tight the fireplace chimney may be the best source of this air. A range hood or a clothes dryer are other exhaust sources that may contribute to the problem. You can reduce the problem by installing a tight fitting damper at the top end of your fireplace chimney and by providing a source of fresh air to feed your furnace. Ask a chimney technician about the damper and a furnace technician about the outside air intake for the furnace.
How can the odor of moth balls be removed?
The usual way to get rid of moth ball odors is a thorough airing in warm temparatures. The odor readily evaporates at temperatures above 80 degrees Fahrenheit. Dry cleaning is also an effective way to remove the odor. The substance in moth balls, paradichlorobenzene has been linked to cancer and can cause explosions if exposed to flames or high heat.
Is installation of new carpeting likely to cause health problems?
For several years, there has been concern that vapors, known as volatile organic compounds or VOC’s, released from new carpet may cause health problems, such as respiratory irritation and headaches. A number of VOC’s are associated with carpeting, pads, adhesives and seam sealers. To date, there is little agreement on whether any of these VOC’s account for carpet-related health problems.
To reduce the chance of health problems after carpet installation, choose a product that has a Carpet and Rug Institute (CRI) indoor air quality label. Use an installation system that does not require adhesives, which are the largest source of VOC’s. Finally, have the carpet installed at a time when you can provide extensive ventilation for 72 hours following installation.
Is ozone dangerous?
Ozone has been used to purify drinking water and to disinfect mildewed boats. But ozone is not widely accepted as an effective way of cleaning air. In fact, ozone is a toxic gas, a component of smog, with no known beneficial health effects.Advocates of ozone generators argue that ozone is extremely unstable and will change the chemical structure of some pollutants resulting in compounds that are more benign to human health.Detractors of ozone generators agree that ozone (O3) is extremely unstable, but they point out that tests have not found that ozone generators remove particles and pollens from air. Furthermore, the detractors point out that ozone is a toxic gas, and the Food and Drug Administration claims ozone has a no known medical, preventative or germicidal application at or below the levels which are considered safe, 50 parts per billion. The ozone detractors point out that most generators produce ozone at levels above 50 parts per billion. At these higher levels ozone can anesthetize and irritate the nasal passages and membranes.
Pressure Treated Lumber
With the concern about arsenic leaching from pressure treated wood what can we do with existing pressure treated wood in our yard?
There are several things that you can do to reduce the risks that you and your family may encounter from existing CCA pressure treated wood structures. First, be sure that children wash their hands after playing on pressure treated wood play structures and discourage them from playing in dirt at the base of any pressure treated structure.Second, consider coating the structure with a semi transparent stain or other water repellent. According to preliminary work at the U.S. Forest Products Laboratory in Madison, Wisconsin, this can reduce the leaching of arsenic dramatically. Sealing the wood is something that you should be doing anyway to extend its life. While pressure treated wood is decay resistant it is subject to damage from ultraviolet light and from water. Applying a penetrating stain or water repellent can reduce this damage. These coatings need to be renewed every few years to be effective. While paints and varnish will reduce arsenic leaching even more efficiently, they have the disadvantage of cracking with time and requiring sanding when they are prepared for recoating. The sanding may release arsenic.
Can anything be done to reduce radon levels?
Standard reduction procedures (mitigation) include sealing cracks and holes in the basement floor and walls to reduce entry. However, just sealing cracks and holes is rarely an effective way to drop radon levels significantly. The most common way to reduce radon levels is to create a field of lower pressure under the home by installing a pipe and fan to draw the soil gases from under the house and exhaust them to the atmosphere above the house. This type of system collects the soil gases before they enter the house. A complete mitigation can cost between $800 and $2,000.
If radon is in the soil, how does it get into a house?
Radon is a gas. Gases tend to diffuse to areas of lower concentrations. The basement or crawl space of a house is such an areas. Chimneys, clothes dryers and the natural boyancy of air tend to increase the movement of radon into the house.
Is it a good idea to have a home tested for radon if neighboring homes have reported high levels of radon?
Yes. While neighboring homes can vary dramatically in radon levels, the fact that neighbors have high levels is a good reason to test. Tests are cheap and easy to do. The usual type is a screening test that takes a two- or three-day sample of radon levels in your home. If possible do the test in winter, when radon levels are likely to be highest, the ground is frozen, your home is closed and your heating system is operating. For more information on radon testing, visit the web site.
What is radon?
Radon is a colorless, odorless gas produced by the decay of radium (which is produced by the decay of uranium). Deposits of radium and uranium are common in the rock and soil. Studies have shown that exposure to radon gas and its decay products can increase the risk of lung cancer. The risk of developing lung cancer is related to the concentration of radon in the air and the length of time an individual is exposed.
Where can I get more information about radon?
For more information about radon, radon reduction, testing for radon, or finding a contractor to install a reduction system, contact your County Health Department, or in Wisconsin call the Radon Information Center at 1-888-569-7236 or on the web go to: http://dhs.wi.gov/DPH_BEH/RadonProt/index.htm.
Why should I be concerned about radon?
Radon gas itself is not a major health concern. The real problem is that radon continues to decay, producing other radioactive materials and emitting radiation. The new materials produced by the decay of radon are solids which readily attach to dust particles in the air, they then can be inhaled. These radon decay products are also radioactive and continue the decaying process producing new solids and emitting additional radiation. In the lungs these decay activities can cause damage to the sensitive tissues. There is a clear, strong, and convincing link between exposure to radon and its decay products and lung cancer.
Basements > Hiring a Water Proofing Contractor
Remove Smoke and Odors
How can I get rid of the cigarette smoke in my house?
The best solution is for the smoker to confine smoking to one room which others avoid and use a small exhaust fan to remove air from that room. This is the solution commonly used in commercial systems. There are also large room air filters that can be effective for a small area. There are also two types of air cleaners to be avoided. The first are desk top models. They typically don’t move enough air through them to have much of an impact. The other type is a heavily marketed cleaner that uses ozone to clean air. Ozone is very effective at cleaning air however, at levels high enough to clean air it poses a health hazard. The makers of this product have been sued by various states and have been investigated by Wisconsin Consumer Protection for misleading claims.
How can the odor of wood smoke be removed from a home?
Smoke and fire restoration specialists have special equipment and chemicals to deal with soot and odors. If the problem is severe, contact such businesses for estimates. Your insurance agent may be able to help you locate them. If you want to try to remove the odor yourself and you have painted walls, use a mixture of four tablespoons of trisodium phosphate (TSP), two tablespoons of chlorine bleach and one gallon of water. Wash from the floor up, then rinse carefully. Do the ceiling last.
Is there a test to tell if an odor in a home is coming from sewer gas?
If there is any smell of gas in the house and it is served by lp or natural gas you should immediately contact the company supplying the gas. Sewer gas often contains methane. The gas company’s test probably will detect high levels of methane, as well as their gases. Unfortunately, one of the odors from sewer gas is often a sulphur compound that can be detected by the human nose at levels that are hard to detect with equipment. The best approach if you suspect sewer gas is to check for possible sources. Dry traps in floor drains or a blocked vent stack are likely sources. Or, ask a plumber to check for leaks. Plumbers often have gas detectors that can help locate gas sources.
Do I need to worry about Stachybotrys?
Stachybotrys is a species of fungus linked to the deaths of several young children. However, other health effects in healthy adults have not been clearly established. Fortunately, stachybotrys appears to be slow growing and flourish primarily where there has been prolonged flooding or water damage. It has been found on the paper coating of wall board,, carpeting and other building products with a high cellulose content. It is black and sightly shiny when actively growing. When dried it has a powdery appearance. Because the fungus is not easily airborne air sampling often fails to detect it. Public health officials point out that many other species of fungus can cause health problems. Therefore, it makes sense to be alert to any household mold problem particularly after prolonged wetting of any part of the house. For small amounts of mold, healthy adults should able to do the clean up without serious health effects. However, for larger areas of mold particularly in confined spaces consider hiring a restoration contractor. These folks have protective breathing gear and special cleanup equipment and knowledge to do the job safely and thoroughly. See also below section on Treating Persistent Mold for more information.
Treating Persistent Mold
How can I remove surface mold?
To eliminate potential health problems, mold must be removed not just killed. The recommended approach depends on how large the area of infestation is and whether the infestation is merely a surface problem such as is often the case with mold on exterior paint. For small areas (10 square feet or less), particularly when the mold is clearly a surface problem.
- Scrub the area with a solution of about an ounce of full strength household detergent (about 1/3 cup); one cup of 5 percent household bleach solution (sodium hypochlorite) and 9 cups of water. Let the solution remain on the surface for about 15 minutes. (Caution: be sure the detergent does not contain ammonia.) Bleach is a strong chemical and should be used with respect. Follow the directions on the container carefully. Use rubber gloves and avoid skin contact. Open windows and run fans to insure adequate ventilation.
- Rinse to remove the remaining cleaning solution mold residue. Flush all cleaning solution and rinse water down the toilet.
For larger areas and particularly for areas that are confined, such as crawl spaces the mold health precautions should be taken.
- Remove and replace porous material such as wall board or ceiling tiles. These usually can not be effectively decontaminated if mold has gone beyond the surface.
- Clean wood and masonry with the detergent solution described above.
- Rinse carefully to remove dead mold material.
- If any mold remains remove it mechanically. This requires special breathing equipment, containment of the area and is best left to professionals.
Unvented Space Heaters
Are Unvented Heaters a Good Supplemental Heat Source?
All types of unvented combustion space heaters are illegal to use in one and two family homes built in Wisconsin since 1980. The prohibition is listed in Chapter 23.04(1b) of the Uniform Dwelling Code. Many Wisconsin communities have ordinances prohibiting their use in all residences. The basic concern is that all combustion products from the heater by definition are released into the room air. Since the early 1980s unvented space heaters have been equipped with an oxygen depletion sensor that turns off the heater if the level of oxygen in the vicinity of the heater drops below a certain point. Low oxygen levels can lead to the production of carbon monoxide. However, an accumulation of air borne debris such as pet hair could clog the burner or drafts from nearby air inlets could effect combustion in such a way that carbon monoxide is produced. Another combustion product is nitrogen dioxide. Nitrogen dioxide can irritant the throat and eyes and cause shortness of breathe particularly in children and persons with respiratory illnesses such as asthma. It is one of the major concerns with smog. Critics question whether the standards for this gas set by manufacturers are really safe. The major product of combustion is water vapor. A large heater can produce nearly two quarts per hour. While water vapor itself is harmless a common problem in our climate is excessive indoor humidity during the winter. This humidity can lead to condensation on windows and other cool surface and the growth of various molds and other biological contaminants.
Does ureaformaldehyde insulation cause health problems?
Ureaformaldehyde insulation (UFFI) is a type of foam insulation that was blown into the walls of homes in the late 1970s. The state of Wisconsin has required that prospective home purchasers be told about its presence since formaldehyde is a severe irritant to many people and formaldehyde from the insulation was often released into the air of the homes insulated with it. This so-called ‘outgassing’ declines in a few years after installation to the point that it is not a concern. Given the fact that UFFI has not been installed in homes for many years there should be no need to worry about high levels of formaldehyde gas in the home from the insulation.
How do we determine if a heat recovery ventilator (HRV) makes sense for us?
The first question is whether you need whole house ventilation. Many older homes have enough natural ventilation without adding a powered ventilation system. In others running existing exhaust fans will be enough. However, for new tightly constructed homes a whole house system may be needed. For cold climates an analysis done by scientists at the Lawrence Berkeley Laboratory in California (LBL) found that a balanced ventilation system that has fans to bring in air as well as to exhaust stale air is most cost effective. In fact, the report recommends a heat recovery ventilator system that recaptures some of the heat from the exhausted air.If you are not sure whether your house is tight enough to justify the cost of installing an HRV consider having an energy assessment of your done. Be sure the assessment includes an air leakage test. In Wisconsin you can find out about energy assessments by contacting the Focus on Energy Program through the following web site at http://www.focusonenergy.com.