An Introduction to Indoor Air and Environmental Quality
Every day people perceive an indoor environmental quality issue, problem or deficiency with their built environment
July 8, 2013
You can go from hero to zero in a New York second if your restoration and remediation activities degrade the indoor environment by disturbing or creating what I like to call bad “stuff.” But before you can protect the indoor environmental quality (IEQ) from any particular “stuff,” you need to understand some IEQ basics.
Humans are indoors all the time, spending vast amounts of their lives inside homes, vehicles and workplaces. Indoor spaces were created to separate us from undesirable external influences, be they the real or perceived. Shelter is at the very foundation of our physiological (body) and psychological (mind) needs. People desire shelter from the sun, the cold and pesky critters. People want security from burglars and privacy from curious neighbors. Most people need little convincing that without shelter they could die from exposure to the elements, but what often surprises people is the mental duress that occurs when they become unsheltered (e.g. displaced by fire or flood) or when they have a breach in the safety or security of their structure (e.g. contamination, infestation or robbery).
IAQ vs. IEQ
Every day people perceive an indoor environmental quality issue, problem or deficiency with their built environment. Some use terms like “indoor air quality,” (IAQ) while others use terms like “indoor environmental quality” (IEQ). I prefer “IEQ” because many constituents of concern in the indoor environment are not necessarily airborne. For example, Clostridium difficile, MRSA, Hepatitis A&B, meth lab residues, noise and many other common environmental issues indoors are not air quality issues, but instead are hand-to-mouth, surface or energy issues. Some hazards can be both airborne and surface contaminants, such as lead dust, which not only poses an inhalation hazard but also carries a strong risk of hand-to-mouth transfer.
Too Broad vs. Too Narrow
When people request an IEQ assessment, they often ask for everything under the sun, or they have a very specific target in mind. Testing for everything is too broad. This shotgun approach is an impossible request, is cost prohibitive and often misses the mark. Conversely, requests to test for only one thing can be too narrow. The IEQ flavor of the month is often what we are asked to assess. I can usually tell what news stations aired the night before by the calls we get each morning. Because “Joe news anchor” mentioned it with verve and confidence, they want methyl-ethyl-death testing, for example. In all fairness, methyl-ethyl-death could be the singular problem for them, but it is important to look at the big picture and not just focus on the hot topic.
What is Good IEQ?
Having good IEQ is an inarguably good idea. But, let me ask you - what do you think defines good indoor environmental quality? Depending on who is asked, I get a wide variety of responses. Experience tells me that your average citizen faced with the question “What is a good indoor environment?” responds with a well-intentioned, but unrealistic concept that roughly translates into something like: “A good indoor environment is a place with zero contaminants and where habitation will produce absolutely zero acute (short-term) and zero chronic (long-term) adverse health effects or discomfort in 100% of the population, 100% of the time.”
Unfortunately, no such utopian environment exists, indoors or outdoors, on or off the planet. Why? Because every environment contains contaminants and individuals are unique in their immunity, allergy profile and bioburden.
In my time as an IEQ expert, I have developed my own abridged definition of “good IEQ.” As with all things abbreviated, it is an oversimplification of an infinitely complex set of factors. In “the gospel according to Derrick Denis,” good IEQ is ambient, comfortable, compliant and safe.
I once was quoted in the Arizona Republic stating, “The air in your house should be as good as outside. If you can’t handle what’s outside, you should move.”
Out of context, this makes me sound like a real curmudgeon, but it’s reality. The line of reasoning supporting this statement is easily summarized with the typically computer-related acronym “GIGO,” or “garbage in, garbage out.” Indoor air is simply outdoor air that infiltrated, or was delivered to, the structure. So if there are undesirables in the outdoor air (e.g. mold or pollen, odors, dust or gasses), you can be sure those undesirables are in the air indoors. And if they are indoors, then you and everyone else will be exposed at some concentration.
A common misconception is that HVAC filters improve indoor air quality. Well, they don’t - at least not directly. HVAC systems in modern and older buildings are designed to modify the temperature of the air by cooling or heating it. A byproduct of cooling is often dehumidification. Without overcomplicating things, that is essentially the “conditioning” part. The filter on your HVAC unit is designed to stop grasshoppers (to quote Charlie Wiles) and to protect your mechanical equipment. More specifically, typical HVAC filters keep coils clean, make the system run more efficiently, prevent condensed water on coils from blowing droplets into downstream ducting, keep condensate drip pans free of ick and prevent condensate drain lines from clogging. Failure of the above listed items can degrade IEQ with consequential results such as odors, spills and mold. But again, the HVAC filters do not improve IEQ directly.
Now you are getting adamant, and you are about to say that you have a high-efficiency filter, maybe even a HEPA filter. Good for you, but filters are for particulates, so gasses (toxic or otherwise) are unimpeded by fancy filters. If you don’t believe me, imagine using a HEPA-filtered respirator in an oxygen-deficient environment or a carbon monoxide-rich environment. Now, imagine your spouse cashing a check sent by your life insurance carrier in your absence. No matter where you live, the outdoor air is generally referred to as “fresh” air. If you have difficulty with the fresh outdoor air (pollen counts, mold counts, pollution, etc.) you will likely experience problems with the air indoors. Indoor air should not be expected to be less polluted than outdoor air. In fact, we presume air pollution will be slightly worse indoors due to the activities of building occupants. Building owners and managers can therefore only be expected to provide you cooled or heated air that is similar to outdoor air in terms of pollutants.
When it comes to the comfort parameters of odor, temperature and humidity, the environment indoors should be comfortable for at least 80% of occupancy. You cannot please everyone, but a well-designed and well-maintained building that is constructed in the correct geographic location and operated with comfort parameters in mind should result in a comfort approval rating well above 80%.
- Odor: Just because a building smells bad doesn’t mean it poses a hazard and vice-versa. A building that smells bad may or may not be healthy, but at a minimum it is distracting and uncomfortable. Likewise, an indoor environment that smells too good can be equally distracting.
- Temperature: Employees who are too cold, either locally (hands, nose, feet) or uniformly (core temperature), can suffer productivity and morale losses, plus their insufferable teeth chattering annoys the customers. Overheated employees risk suffering a fate of continuous complaints about discomfort.
In conjunction with both odor and temperature dissatisfaction, you often see creative and sometimes dangerous occupant remedies that carry their own liabilities (e.g. taped over registers, rows of space heaters, potpourri bowls, aromatherapy oil lamps, etc.). Facility managers and building owners have to keep these activities in check or the electric bill rises, power loads on critical circuits exceed design, risk of fire increases, HVAC systems cannot perform per design, etc. Plus it looks shabby and gives the impression that management is nonresponsive to the pleas of the plebs.
- Relative Humidity: Relative humidity is a term R&R readers are likely quite familiar with, since many of you respond to water incursions. As masters of psychrometry, you skillfully convert wet buildings into dry buildings. But, in terms of IEQ comfort, a building that is too humid can be perceived as stuffy. High humidity, or a low dew point, can also be problematic. Keep in mind, condensation can lead to secondary environmental degradation, such as mold and bacterial growth. Conversely, if the relative humidity is too low, indoor air will be perceived as too dry and can result in itchy ashy skin, dry, irritated eyes, nose bleeds, chapped lips and the need to apply voluminous quantities of moisturizers.
When it comes to good IEQ, it is important not to violate industry doctrine. There are loads of laws, stacks of standards, gobs of guidelines and bunches of best practices for virtually every IEQ constituent. You should be familiar with the ones that affect your work. Here are a few terms with which you and your team should already be familiar:
- Occupational Safety and Health Act of 1970
- EPA National Emission Standards for Hazardous Air Pollutants (NESHAPS)
- EPA Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)
- ASTM E 2356 – 04 “Standard Practice for Comprehensive Building Asbestos Surveys”
- IICRC S500
- IESO/RIA 6001-2011 “Evaluation of Heating, Ventilation and Air Conditioning (HVAC) Interior Surfaces to Determine the Presence of Fire-Related Particulate as a Result of a Fire in a Structure”
- EPA 402-K-01-001 2008 “Mold Remediation in Schools and Commercial Buildings”
- NADCA’s ACR 2013 “Standard for Assessment, Cleaning & Restoration of HVAC Systems”
There are many potential indoor environmental hazards (and disorders associated thereto). There are chemical contaminants like chlorine (pulmonary edema) and carbon monoxide (asphyxiation). There are biological contaminants like bacteria, such as Legionella pneumophila (Legiolellosis) and MRSA (necrotizing fasciitis), and fungi such as Coccidioides immitis (Valley Fever) and Aspergillus niger (aspergillosis). There are physical contaminants such as asbestos (mesothelioma) and silica dust (silicosis). There are energetic contaminants such as ultraviolet light (skin cancer) and x-ray radiation (radiation sickness). Each of these mentioned, and the infinitely larger list of unmentioned hazardous contaminants, can be harmful and even fatal in the indoor environment.
So in order to have good IEQ, the air inside should be free of hazards at CONCENTRATIONS OF CONCERN. Note the capitalization of the phrase “concentrations of concern.” This is to help keep things in perspective. Measurable hazards are all around us. With every breath of air, you inhale some measurable concentration of radon, asbestos fibers, mold spores, bacteria, virus, cat dander, carbon monoxide, insect parts and a whole lot of other things that will creep you out if you dwell on them too long. In every sip of water, you ingest some measurable amount of lead, arsenic, trichloroethylene, PCBs and a lot more scary sounding fun “stuff.” Go outside and try not to be exposed to ultraviolet radiation from the sun. Paracelsus, the generally undisputed father of toxicology, stated, over 500 years ago: “All things are poison, and nothing is without poison - only the dose permits something not to be poisonous.” This is commonly condensed to read “The dose makes the poison.”
What is important to consider is that “detectable” does not necessarily equate to “dangerous.” This is especially important to keep in mind, since the limits of our detection technology continue to improve, thereby enabling us to identify and quantify smaller and smaller amounts of “stuff.”
If environmental hazards are at concentrations of concern, then you should respond accordingly to ensure the safety of your team and others. Safety is more important than profit, quality, schedule or customer satisfaction. If you cannot perform the work safely, you should not perform the work at all.
In summary, good IEQ is ambient, comfortable, complaint and safe. If your restoration or remediation activities maintain or provide this type of environment for your team and for the occupants of the buildings while you work and after you leave, you will be an IEQ hero.