Indoor Air Quality

Information provided here in this website is to assist people in understanding these topics. This information should by no means be considered all-inclusive or exhaustive. The links on this site they can help provide more information as well as other available sources.

Construction techniques over the last many years have resulted in homes being more tightly sealed to save energy. The increased use of synthetic building materials and furnishings and the increased use of chemicals in the home by the occupants, may it be pesticides, cleaning supplies or personal care products have contributed to a decrease in the quality of indoor air. Older homes, because they were not as tightly sealed had better air exchange rates (how many times the interior air is replaced by exterior air). While we were making our homes more airtight we were moving away from kitchen exhaust fans that terminate to the exterior, bathroom exhaust fans with adequate draw that terminate to the exterior, etc. We have generally as a society relied on central air-conditioning and heat, which unless the systems have an exterior air source are just pushing the same air through the home, and potentially distributing: mold spores, combustion gases, volatile organic compounds, etc. The result is that more people developed health problems with no idea of the cause. Symptoms of poor indoor air quality are often misdiagnosed by general practitioners. Environmental physicians are required to have two additional years of medical school. Ideally todays homes should have whole house ventilation, although this is rarely the case. So what do we do? We take this into account when inspecting a home regardless of age. We look for potential areas of improvement and make appropriate recommendations. We educate ourselves at least to a degree where we can make decisions to improve indoor air quality, after all it is our health that we are referring to. I have learned over the years to start with the basics. Improvements do not necessarily have to be expensive. Awareness and habits in the home combined with proper ventilation and system maintenance can go a long way to improving indoor air quality.

More information can be obtained through the links on this website and from other sources.
A brief discussion of mold, radon, gas leak, carbon monoxide, water testing and other sources that may affect your indoor air quality are discussed here in this website. If you find that any of these links do not work please let me know and I will get you the information and try to get the links active.

As a home inspector experienced in water intrusion analysis and moisture control I will be looking for conditions that are conducive to mold growth at your inspection as well as signs of or conditions conducive to contributing to other sources of contaminated air in the home.

I have a national mold certification and I am part of a mold testing program that has a team of environmental analysts. This team in conjunction with the mold testing laboratory has a biologist, a microbiologist and a mycologist. This team analyzes the samples and they contact you to go over the results and recommendations.

Although I do not push extra services on anybody and they are routinely not needed, having a home inspector experienced and qualified to perform some of these tests during a home inspection or prior to the end of your inspection clause in your real estate contract can be of great value. If you have an air quality concern or if we see conditions that warrant further testing during an inspection than we can test as needed. Anything that can be discovered and addressed during your negotiation period will potentially save you money, give you peace of mind and a healthier home to live in. If nothing else I like to create an awareness and provide some education to clients so they can consider sources or conditions of potential problems in there in their interior environment from mold to gas explosions.


Molds are a needed part of the natural environment. Abnormal or excessive amounts of interior molds have the potential to cause health problems and property damage. Allergic responses include: sneezing, running nose, red eyes, and skin rash. Reactions can be immediate or delayed. Mold exposure can irritate the eyes, skin, nose, throat, and lungs of both mold allergic and non-allergic people. Molds produce allergens (substances that can cause allergic reactions), irritants, and in some cases, potentially toxic substances (micro-toxins). Because mold affects everybody differently a previous or current occupant of a property that did not complain of any mold-like symptoms does not mean a newer occupant would not produce symptoms. Certain mold species may cause serious illness in the elderly, infants and people with weak immune systems. Mold Spores may begin growing indoors when they land on surfaces that are damp or wet. A few of the most common contributors to a mold growth environment include: poorly maintained HVAC systems, roof or plumbing leaks, construction defects or deterioration, dryer or other vents terminating indoors, inadequate or no bathroom/kitchen ventilation, and proper grading around foundations. The key to preventing mold growth is moisture control. Note that if the originating source of moisture/water is not determined and fixed the mold problem will likely come back.

Testing for mold – Mold testing should be done by an independent and certified third-party that has no interest in the results of the testing because that they do not provide mediation services. We test for mold when there are musty and or moldy odors, after major water events such as flooding or leaks, when water has been known to be present for more than 24 hours, when staining is noted on building materials or furniture, and when occupants experience mold like symptoms without a known cause.
Proper mold testing confirms if the mold-like substances are in fact mold, or if no visual signs were present, testing confirms if mold is in the air. Mold testing distinguishes the types and concentrations or quantities of the molds. This information is needed to conduct proper remediation if in fact cleaning or remediation is needed based on the test results. Proper mold testing includes an exterior air sample that is used as a baseline in comparison to interior samples. A simple swipe or sampling of a mold-like substance sent to a laboratory does not accomplish this. Post mold tests are used to determine if an area has been adequately cleaned or remediated.
Mold remediation – Mold remediation has improved over the years and has become much less expensive in many cases. Some mold treatments now do not require demolition or the removal of materials. Similar to radon, which years ago was considered to be a big deal, which it still can be from a health standpoint, is easily and cost-effectively remediated. Many of the mold remediation jobs today are nondestructive and cost-effective. Properties that have suffered severe or major water damage can be quite expensive to remediate.
If you see and suspect you have mold:
Do not clean with bleach, Bleach contains approximately 70% water. Do not disturb, avoid breathing in mold or mold spores. According to EPA guidelines small areas less than 10 ft.² under certain conditions can be cleaned using tips and techniques found in their literature. Larger areas and areas that have water damage should be handled by qualified remediation specialists. More can be read about mold, causes of mold, health effects, testing and remediation, etc. in the links of this website and from other sources.


A link to the North Carolina Radon Program is provided here on my website.

Radon is a naturally occurring radioactive gas. Radon comes from the rocks and soil below and around your home. Radon gas is invisible, odorless and tasteless. It enters your home through cracks and openings in the foundation and/or from areas below the home such as crawlspaces and slabs. Radon can also come through your drinking water supplies, mostly from private water wells versus public/city water. Radon is the second leading cause of lung cancer after smoking. More than 20,000 Americans die from radon related lung cancer each year. Radon can reduce the average lifespan by 17 years.
Testing for radon – The most common means of testing is with what’s called passive devices.
This group includes: Alpha track detectors, charcoal canisters, and charcoal liquid scintillation detectors. These are the devices typically purchased by a homeowner and used by many inspection companies. The potential problem with these devices is that they can be tampered with, they are prone to interference by high humidity, if set longer than manufacturer’s instructions they can become saturated and therefore the readings are no good. To be used correctly many need to be placed two simultaneously or to two sequentially. In actual practice this is rarely done. The biggest problem with passive testing devices is that they are known to be inaccurate. Unfortunately, when used in a real estate transaction, somebody could be buying a mitigation system unnecessarily or someone could actually need one and not know it.
Active devices – These devices are known as continuous monitors. Continuous monitors take readings hourly, these readings are printed on a graph. It can be determined if the units have been tampered with and they are extremely accurate. These devices are not for homeowners as users need to be trained in their operation. If by chance you are in an area that you would like a radon test done, I am certified in radon testing, I only use electronic continuous monitors that are calibrated by the manufacturer on a yearly basis and are placed in accordance with EPA guidelines. I do not recommend the use of passive testing devices.
How is radon measured? – Radon is measured in pico curies, pCi/L, pico curies per liter of air. The typical action level for a real estate transaction is 4.0pCiL/L. That is the level at which remediation is recommended. 10,000 pCi/L of radon in water ads 1 to the level in the air.
The action level for radon in the water is 5000 pCi/L.
Mitigation in air – The most common type of mitigation for radon in the air is a subsoil depressurization system. These systems typically average about $1500.
Mitigation and water – There are generally two types. Gac (granular activated charcoal), which can be used at up to 10,000 pCi/L and aeration types with plates or bubblers. These systems are used when the levels are above 10,000, but should be considered as an alternative to Gac systems because Gac systems hold and store the radioactive charcoal. Aerator systems typically cost approximately three to $5,000, while charcoal systems can be as low as $2,000.

Gas Leak

Natural gas and propane are flammable and explosive. Both are odorless and colorless, but gas companies add a rotten egg smell. Propane can lose its odor. Natural gas is lighter than air and propane is heavier than air.

Either gas can mix with the air or can be moved by air currents such as convection and could be found at any elevation. Gas leaks can be detected with a soap and water solution. The preferable method is to use a gas leak detector and to confirm detected leaks with a bubbling solution. The inspection is limited to accessible components, fittings, connections, valves etc. Although most gas leaks found during a gas leak inspection are small and would likely not cause an explosion, larger leaks are found and lives are saved. Finding and repairing even a small leak can prevent that leak from worsening over time. Often these leaks are from older gas valves that are no longer approved for use. I recommend the use of plug-in gas leak detectors. The detectors should be rated for the gas type and should be installed according to manufacturer’s instructions. You should become familiar with the alarm sound, so it would not be confused with a smoke alarm. You could possibly wake up in the middle of the night or come home confusing it with a fire alarm and turn on light switches or other acts that could cause an explosion.
What to do if you smell a gas leak or your gas leak detectors are going off – Do not do anything that is likely to cause an explosion including: operating electrical switches or telephones, or lighting a match or lighter.
Notify any other building occupants and leave the building. Move at least 100 feet away and contact the gas company and fire department.


Home Inspections and Beyond does not offer testing services for carbon monoxide because dangerous or elevated levels of carbon monoxide may not be present at time of the inspection. Carbon monoxide levels can be affected by many things. Some of them include: the conditions under which fuel-burning appliances are operated, the exhausting of burned fuels can be affected by drafting characteristics of the appliances, the opening and closing of windows and doors, the operation of fans, close dryers etc. The fact that dangerous levels of CO are not present in a building at time of testing is no guarantee that dangerous levels of CO may not occur even moments later. It is recommended to have carbon monoxide detectors installed according to manufacturer’s instructions which typically includes one on each level of the home outside of the bedrooms.
Much of the information provided here on carbon monoxide was taken from the consumer protection safety commission (CPSC). I had provided a link to the site.
What is carbon monoxide – Carbon monoxide (CO) is odorless, colorless, is not detected by human senses and is deadly. It is produced by the incomplete combustion or burning of fuels in appliances such as furnaces, ranges, water heaters, room heaters, fireplaces, and also from the use of generators and the running of cars in confined spaces. The fuels include: coal, wood, charcoal, oil, kerosene, propane, and natural gas. Many people die each year from CO poisoning and thousands more are treated at emergency rooms. The initial symptoms include: headache, fatigue, shortness of breath, and dizziness. High levels of CO poisoning include: mental confusion, vomiting, loss of muscular coordination, loss of consciousness and death. A carbon monoxide blood tests can be conducted if you think you have been exposed. Similar to flulike symptoms associated with mold, symptoms of CO can be mistaken for the flue.
How to prevent CO poisoning – A partial list. All fuel-burning appliances are to be installed and operated according to manufacturer’s instructions and local building codes. Fuel-burning heating systems, including flues and chimneys should be professionally inspected and serviced annually. The venting of the kitchen gas stove should be to the exterior for CO and other indoor air quality reasons. Never use gas appliances such as ranges, ovens, or close dryers to heat your home. Never operate any unvented fuel-burning appliances in any room where people are sleeping, unvented or vent less gas fireplaces/appliances release combustion products, including CO into the indoor air and decrease the level of indoor oxygen supply. Manufacturer’s operating instructions should be followed. A check can be made to see if houseplants are dying. Condensation on cool surfaces in the house can be a sign of the presence of exhaust or flue products.
What to do for CO alarm sounds – Immediately move to the outside. Call emergency services, fire department or 911. Confirm all occupants are out of the dwelling. Do not reenter until emergency services have given you permission. If the source of the CO is determined to be a malfunctioning appliance, do not operate an appliance until it has been properly serviced by qualified personnel.


Home Inspections and Beyond does not offer testing services for VOCs. Testing for and measuring all VOCs present in a home is difficult and the testing varies greatly depending on type of compounds present. Testing multiple locations and types can be very expensive. There are no federal or state standards for VOC levels in the home. I am in no way saying that testing should not be done. Sources such as the EPA and others have extensive information on the subject. Again as part of my brief overview as to some of the things that can affect your indoor air quality I am presenting this limited information. I do recommend source control, by removing and reducing the number of products in your home that give off VOCs and by using proper ventilation techniques and maintaining proper temperature and humidity in the home. If the home is newer or has been recently remodeled there will be higher levels that will off gas over time.
What are VOCs – VOCs are chemicals that are found in many products we use to build, maintain and clean our homes. They include both-human made and naturally occurring chemical compounds. For this discussion we are concerned about the ones that affect our indoor air quality. Some VOCs are dangerous to human health.
Common examples of VOCs that may be present in our homes are: benzene, ethyl glycol, formaldehyde, methane chloride, tetrachloroethylene, toluene, and 1,3-butadiene. Sources of building material VOCs include: paint, varnish, caulk, adhesives, carpet, vinyl flooring, composite wood products, upholstery and foam. Sources of home and personal care product VOCs include: air fresheners, cleaning products, cosmetics, fuel oil, and gasoline. Types of activities that produce VOCs include: smoking, dry-cleaning, photocopiers, cooking, hobbies, and burning wood.
Health effects of VLC exposure – Among the health effects of high levels of exposure include: eye, nose, and throat irritation; headache, allergic skin reaction, nausea, vomiting, nose bleeding, fatigue, dizziness.
Chronic exposures of years to a lifetime can include: cancer, liver and kidney damage, central nervous system damage.
Some steps to reduce the levels or your exposure to VOCs – Remove or reduce the number of products in your home that give off VOCs. Store unused chemicals in a garage or shed where people don’t spend a lot of time. Properly dispose of unused chemicals that are stored in your home or garage. Check with local city or county agencies in this regard. Consider purchasing low VOC options of paints and furnishings, house cleaning products etc. Solid wood items with low admitting finishes will contain less VOCs than items made with composite materials.
Ventilation and climate control – Increasing the amount of fresh air in your home will help reduce concentration of VOCs indoors. Of course we need to consider exterior humidity, temperature etc.
Keep both the temperature and relative humidity as low as possible for comfort. Chemicals off gas more in high temperatures and humidity. Try to perform home renovations in the house when is unoccupied or during seasons that will allow you to open doors and windows to increase ventilation.


As with other subjects on my website this basic information is meant to bring awareness in regards to the quality of our water supplies. Please see the links to the EPA and other sites for more information. This section generally talks about private well water.
You should consult with your lender in regards to any required water tests. FHA and VA loans typically have water testing requirements for private water sources. Some lenders may require a septic or a septic dye test to be performed, for private septic systems. I recommend contacting the local health department in your county for water testing information that can be specific to the area in which you are purchasing property. Many of us with private wells have experienced hard water, which is typically high in calcium and magnesium. We commonly treat hard water with a water softening system, and I sometimes find that people associate and/or assume that this water softening system is also treating the water for other potential problems. Also if a home is tested for radon in the air and the results are negative, it does not mean that radon is not present in your well water, the two are not connected to each other, one is not indicative of the other. Water with a low pH (acidic) is corrosive to plumbing and may cause leaching of toxic metals such as lead from pipes and fixtures. These are just three examples. Your water should be safe to drink. In addition to illness, there are other characteristics of the water that can affect taste, color, odor and staining of clothes. Generally we test the private water source for potability, which tests for bacteria and minerals, but depending on the area and the concern water can be tested for VOC’s (volatile organic compounds), radon, lead, arsenic, uranium, etc. In addition to testing the quality of the water, tests can be performed to determine the quantity or volume/flow rate and the function of the equipment. Water can be treated for a variety of reasons, including: hardness, color, odor, turbidity, ph, etc. More information about private wells and the testing of private wells is available from the EPA site.

Do we need to test city water supply? – Look at what has transpired in Flint Michigan and other cities. Do we take our city water quality for granted? There are recent reports about the possibility of VOCs and MTBEs (methyl tert-butyl) contaminants leaching from the newer plastic water supply lines being used in houses now to replace more the expensive copper. You could get contaminants from deteriorating supply pipes in your older home, there could be harmful bacteria in your water heater, etc. Even if the city water is what it’s supposed to be, it may get contaminated by the time it comes out your faucet.
Again, this information as well as other information provided on this website is not an effort to sell testing services or to be an alarmist, this is information to help people have an overall awareness of potential problems with their water or interior air quality.

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