When the U.S. Environmental Protection Agency (EPA) published its seminal report to Congress on Indoor Air Quality (IAQ) in 1989, the HVAC industry raced to provide products and services that would help improve the quality of the air in homes and businesses alike. Almost overnight, the public became concerned with ventilation, filtration, and humidity control issues, and contractors and manufacturers scrambled to find solutions to the sometimes complex problems associated with IAQ.

Since then, associations, such as ASHRAE, and individual states, including California and New Jersey, have put forward standards and regulations that address IAQ issues, but the definition of IAQ still remains somewhat nebulous. Perhaps that is because so many factors affect IAQ — everything from poor ventilation and high (or low) humidity to pesticides, mold, and radon. In addition, it can be a challenge to quantify proper IAQ, particularly when occupants in a space have varying tolerances to different contaminants and irritants.


The EPA defines IAQ rather vaguely, calling it “a term referring to the air quality within and around buildings and structures, especially as it relates to the health and comfort of building occupants.”

ASHRAE, on the other hand, gets more specific, defining it as “air in which there are no known contaminants at harmful concentrations as determined by cognizant authorities and with which a substantial majority [80 percent or more] of the people exposed do not express dissatisfaction.” These definitions are seemingly poles apart, but, in the end, does it really matter?

Absolutely, said Patrick Holleran, president, Field Controls LLC, who states that as long as there is not a standard definition, homeowners will not be able to compare apples to apples. “At the very least, they should be able to make an informed decision about their options and have a basis for making that decision. If HVAC contractors only provide filtration, then how can they address concentrations of airborne germs and volatile organic compounds [VOCs]? If contractors only offer a source of fresh air, how can they keep the coil clean and avoid ‘dirty sock syndrome?’ It won’t make a difference how much you ventilate — you will never achieve true, pure IAQ.”

For the record, Holleran defines IAQ as “air that is fresh, clean, and pure.” The best way to achieve that, he notes, is through fresh air ventilation (dilution), filtration of particulates, UVC germicidal purification, and VOC reduction with photocatalytic oxidation (PCO) or comparable technology. “Consistent, year-round air quality requires a control to cycle the air on a schedule and ensure the air in the home is fresh, clean, and pure — even during shoulder months when not heating or cooling.”

Aprilaire defines IAQ as the conditions that make up the indoor environment of a home, including temperature, humidity, purity, and freshness, said marketing director Mike Rimrodt. However, even within a home, those conditions may be perceived differently by occupants.

“While some IAQ issues impact health, others only impact comfort or only harm some individuals,” he said. “A house may be filled with pollen and pet dander, but if no one in the house is allergic to those things, they likely wouldn’t consider the home to have an IAQ problem. But, if the home is occupied by someone with allergies or asthma, those same conditions could negatively impact health as well as comfort, thus leading the residents to rate their IAQ as very low.”

IAQ should also not be confused with Indoor Environmental Quality (IEQ), noted Rimrodt, which includes any building condition that negatively impacts human health and wellbeing. This could include everything from discomfort caused by inadequate lighting to lack of protection from sustained noises to poor ergonomic conditions that lead to individual stress or injury.

“IEQ is usually addressed by Leadership in Energy and Environmental Design [LEED] and green-building qualifications. While IAQ is a major component of IEQ, it takes specialized contractors to holistically address IEQ concerns.”

Jeffrey May, principal scientist, May Indoor Air Investigations LLC, Tyngsborough, Massachusetts, and author of the book, “My House Is Killing Me!,” believes the definition of IAQ comes down to fresh air and good filtration, but only if the HVAC systems have been properly maintained in the first place.

“I believe the HVAC industry is responsible for the health of the country, because all the air that anyone breathes in a building goes through a mechanical system,” he said. “If that system isn’t maintained properly, then there are going to be issues. The biggest source of IAQ problems, in my experience, is contaminated heating and cooling equipment.”

Air conditioning systems are often the bigger problem, noted May, as the combination of condensate and dust results in microbial growth on the coil and in the drain pan. “The only way to prevent dust in the mechanical system is with good filtration. Most people sell filters by saying they will reduce the number of particles in the air, and that’s important, but that’s not really the purpose of the filter, at least not in terms of air quality. You have to protect the air conditioning coil, the pan, and all that fibrous lining from accumulating any kind of dust, otherwise the system becomes contaminated, and the resulting mold and bacteria will be blown all over the house.”


Given the varying definitions, how can contractors ensure they are covering all the bases when it comes to solving IAQ problems in their customers’ homes? According to Paul Raymer, chief investigator, Heyoka Solutions LLC, the first thing to do is ask questions.

“If the owner is complaining about IAQ, there must be some sort of symptom: mold, dust, congestion, bad smells, etc. The first question to ask is, ‘What changed?’ If the symptoms have only arisen recently, something must have changed in the house. Did they get new carpeting? Did they have a roof or plumbing leak?”

Asking questions is the only way to find out if the house is a healthy home, said Eric J. Legreid, project manager/sales, Air Quality Systems Inc., McFarland, Wisconsin. These are just a few of the many questions he routinely asks homeowners:

• Are there any areas that are too warm or too cold?;

• Does anyone suffer from asthma or allergies?;

• Does the home get too muggy or too dry at certain times of the year?; and

• Do you ever turn on the fan(s) to circulate the air?

“We do not sell furnaces and air conditioning, we sell comfort,” said Legreid. “We want to know what customers want, need, and desire for their homes, and questions like these help us understand their wishes. We can then explain options, such as adding better filters, UV lights, dehumidifiers/humidifiers, and fresh air controls. Then, it comes down to what they can afford.”

Even when contractors ask all the right questions, it can be difficult to track down the reason for an IAQ problem, said Raymer, because there are often multiple sources involved. “On top of that, as houses get tighter, interactions between elements have more impact. For example, installing a higher-volume ventilation system may remove some particulates, but, at the same time, it could put the house under enough negative pressure to draw moisture into the wall system. In multifamily housing, decreasing the pressure in one unit can draw odors in from some other unit and not necessarily the one next door.”

Most of the time, it will be possible to come up with a solution to an IAQ problem, and contractors should take that opportunity to educate consumers on the health and comfort benefits of IAQ products, said Rimrodt. “Customers need to understand the negative impact of improper humidity control, inadequate ventilation, and the health effects of indoor air that can be 100 times more polluted than outside air.”

IAQ products have other benefits, as well, which contractors should stress, noted Rimrodt. “Good air cleaners can prolong the life of HVAC systems by keeping the a/c coil and air handler clean and free of debris. Humidity control can also prevent costly damage to wood floors and the expenses associated with mold remediation. Investing in a high-capacity dehumidifier is also a cost-saving measure because it can outlast and cost less to run than most portable units.”

After all the time and energy spent tracking down IAQ problems and educating consumers about possible solutions, the good news is that homeowners are often willing to invest in those recommended products.

“A recent study showed when homeowners are offered an IAQ solution by a contractor, they were willing to spend more than $600,” said Holleran. “In addition, the study showed 30 percent of homeowners put IAQ on the same importance as energy efficiency. The conclusion for the contractor is this: Offer a comprehensive IAQ solution and let homeowners decide for themselves. According to this study, your close rate will be greater than 30 percent, and, in any sales business, a 30 percent close rate is pretty darn good.”

Publication date: 6/8/2015

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