Indoor Air Quality
Air pollution is commonly thought of as an outdoor air problem, but numerous studies have shown that indoor air pollution is typically worse than outdoor pollution. This is true even in urban centers, where the presence of air pollutants can be anywhere from 2 to 5 times higher indoors. A multitude of factors shape indoor air quality (IAQ). Naturally occurring irritants such as dust, mold, and pet dander can build up. Pollutants also include harmful chemicals that are off-gassed by cleaners, textiles, and building materials. These include volatile organic compounds (VOCs) such as formaldehyde, phthalates, and other banned substances that are nonetheless still present in many buildings, such as lead and asbestos. Radon gas, the second leading cause of lung cancer, occurs naturally but can reach unsafe levels on the lower levels of almost any building.
While the damaging effects of lead and asbestos on our health are well known, the impact of these other common substances is less well advertised and understood. They can cause problems ranging from allergies to headaches. Many of these chemicals are carcinogenic, and are known to negatively impact the nervous and endocrine systems of the body. Formaldehyde, which was introduced into many products as a flame retardant and to prevent wrinkling, and is a known carcinogen and one of the most common causes of contact dermatitis. It can be found in everything from textiles to particleboard. Phthalates disrupt the endocrine systems of lab animals, and exposure to high levels of phthalates has been correlated with obesity in human populations. They are found in certain plastics, including nylon and some PVC, and in the fragrance added to variety of personal care products and air fresheners.
What makes these pollutants and irritants so dangerous inside a building is that reduced air exchange rates allows them build up to unsafe concentrations. Your building system might circulate air throughout the building, but not adequately replace that air with outdoor air, leading to a build up of contaminants. People in the US spend about 90% of their time indoors, explaining in part why the EPA has listed indoor air quality as one of the top five most urgent environmental risks impacting public health.
In addition to posing a serious public health problem, poor indoor air quality impacts worker productivity. The EPA estimates that the medical and lost productivity costs associated with workers breathing poor air in the range of tens of billions of dollars every year. OSHA similarly puts a $15 billion price tag on worker absences and reduced efficiency resulting from poor air quality. These estimates do not include rising costs of lawsuits and the legal liability that companies incur from workers working in unsafe conditions.
Despite the myriad causes of poor indoor air quality, there are several concrete, often low cost steps that you can take to improve that air that you and your workforce breathe. We’ve outlined a guide for getting started below. These steps are divided into easy, medium, and hard categories. While several tips are provided, they are all versions of two basic approaches: reducing and removing sources of indoor pollution, and reducing the concentration of indoor pollutants through ventilation and cleaning.
- Smoking should never be permitted indoors or within several feet of a building entrance. Second hand smoke will not dissipate indoors, and will build up over time.
- Place large doormats outside and inside at entrances. Dust, pesticides, trace amounts of lead, and a host of other contaminants are carried inside on people’s shoes. While you can request that people take off their shoes at the front door of your home, you’re unlikely to want to do this at your place of business. Large doormats, however, trap a surprising amount of these particles, and can later be cleaned.
- Clean regularly. Use vacuum cleaners with HEPA filters, which emit fewer particles back into the air. Damp dust and mop where you are able. This is a great way to trap particulate that vacuum cleaners and regular dusting miss.
- Forgo air fresheners altogether. This includes plug-ins, sprays, and other scented products that are designed to perfume rather than clean your air. Air fresheners mask bad smells that indicate that you need to remediate a problem, such as find and remove mold and mildew. They also add problem compounds to the air. VOCs and phthalates are commonly found in the catch-all ingredient “fragrance” in air fresheners. Six phthalate compounds have recently been banned in children’s toys because of the harm they pose.
- Ensure that your cleaning products aren’t adding to the problem. Avoid cleaners that include any kind of “fragrance,” as well as cleaners that use chlorine or ammonia. There are several good resources online that provide information about the safety of common ingredients in cleaners, including Environmental Working Group.
- Clean up moisture and other spills immediately to reduce the chances of mold and mildew growth. Mold and mildew spores are naturally occurring, but you can control the conditions that encourage growth.
- Skip the tabletop air purifier, but maybe not the indoor plants. Research is mixed on whether or not indoor plants remove VOCs from the air, though they do increase oxygen levels, which can help improve alertness. Air purifiers, of the stand-alone variety, do very little, and are unlikely to impact the air quality in your building overall.
- Install a carbon monoxide detector. These are usually required in new construction, but are a good safety investment for all structures. Especially consider installing these if you have fuel-burning devices in the building, such as gas stoves, water heaters, and space heaters.
- Regularly maintain your HVAC and other building systems. This includes changing air filters.
- Keep moisture levels somewhere in the range of 30 to 50% humidity. This will inhibit the growth of mold and other allergens, and also make occupants more comfortable. Your approach to managing humidity will depend on your climate. Heating systems tend to dry out the air. Adding a whole building humidifier to the system will prevent this problem. Though this will present some initial costs, higher humidity levels should also reduce overall heating costs as the less dry air tends to make people feel warmer. Air conditioning systems will reduce humidity levels to acceptable levels in most climates in the summer, though very dry climates might also employ a humidifier during warm months.
- Determine the air exchange rate in your building. In a small building, you can always open windows to allow in new air and flush out the old. In larger buildings, this is a more complicated issue. Work with a professional to ensure that the building system replaces the air in your building at an adequate rate.
- Apply AFM Safecoat sealants or similar sealants to pressed wood products. This water-based sealant is effective at preventing the off-gassing of formaldehyde and other VOCs present in most pressed wood products.
- Manage pests without pesticides. Pesticides should be a last resort, and there are several resources and methods of pest control, also known as Integrated Pest Management (IPM) that do not require the widespread application of pesticides.
- Invest in testing to identify specific hazards. With so many potential contaminants, your best course of action is to identify the worst offender or offenders and deal with those. This is particularly true if an employee or employees are having recurring health problems that may be linked to the building. There are a variety of tests that you can purchase and then send to a lab that test for VOCs, formaldehyde, radon, lead, and mold. For larger buildings, more accurate testing and evaluations can be performed by professionals.
If at any point you are in a position to remodel or replace furnishings in your building, research the materials that you’ll be replacing. Choose options that have little to no chance of releasing any kind of noxious gas or chemicals and that do not contain problem substances. Fortunately, industry standards are changing due to consumer demand, and there are new laws in place limiting the presence of certain key problem chemicals. Older materials may or may not meet new standards. There are also some companies and certifications to help consumers choose better products, including GREENGUARD Certification.
Additionally, an updated or new air system may be in order. Any new air system should efficiently replace the air in your building and include a system for collecting contaminants.
Common problem materials include:
- Carpet and carpet padding. Carpets trap dust and other particulate, and are very difficult to fully clean. Furthermore, they often off-gas flame-retardants and other hazardous chemicals. Some options are better than others, and may emit fewer VOCs. Some carpet companies, like Merida, manufacture low-emission lines of carpets with better overall environmental impact.
- Particleboard, pressed wood, and plywood. The resins and glues in these are often filled with formaldehyde. Industry standards are changing, and formaldehyde levels have been reduced in many products and eliminated in a few. Newly introduced regulations should set maximum levels of formaldehyde for composite woods, but older products may need to be removed or sealed. All-wood products will not have formaldehyde in them and will last longer, however, pressed wood products reduce pressure on virgin forests. Medium density fiberboard (MDF), commonly used in furniture, has the highest levels of formaldehyde.
- Textiles and fabrics. This includes upholstery and drapes, and very possibly your wrinkle-resistant shirt. These often have been treated with VOCs to reduce wrinkling and to act as a flame retardant. Formaldehyde is a common problem here as well. The presence of flame retardant substances are almost never listed on fabric content label, so you will need to do some research to find out if the fabrics have been treated.
- Paints, sealants, and finishes. Look for low VOC paints and finishes, and finishes that are water based. Your local green building supply company should have good resources on what products are safest. Regardless of what you use, use these products outdoors whenever possible. Let your space air out thoroughly before moving people back into a newly painted or refinished space.
- Fuel-burning appliances. This may not be an issue in your space, but if you have a gas stove, water heater, or other appliance that could be releasing gases through combustion, ensure that these appliances have local ventilation that vent to the outside of the building.
- Lead and asbestos. Lead paint was banned in the United States in 1978, and asbestos has been banned from several building applications, but both are still present in many structures. Though this may be a costly intervention, remediating asbestos and lead from your building is well worth it given their clear danger to human health.
On the topic of indoor air quality, health, and prevention:
Occupational Safety and Health Administration (OSHA), Indoor Air Quality
Environmental Protection Agency (EPA), The Inside Story: A Guide to Indoor Air Quality
Jeanie Lerche Davis, Breathe Easy: 5 Ways to Improve Indoor Air Quality, WebMD
American Lung Association, Indoor Air Quality
Sierra Club, Indoor Air Pollution
On cleaners and building materials impact on IAQ:
Building Ecology Research Group, Practical Ways Building Designers Address Indoor Air Quality Issues?
Green Building, Indoor Air Quality
US Green Building Council’s Green Home Guide
Environmental Working Group, Guide to Healthy Cleaning
On specific chemical and allergenic threats:
Minnesota Department of Health guide to formaldehyde
 That is, they are released into the air in gaseous form.
 “Formaldehyde and Cancer Risk,” National Cancer Institute, accessed 1 July 2013, http://www.cancer.gov/cancertopics/factsheet/Risk/formaldehyde.
 Michelle Castillo, “Environmental contaminants phthalates linked to obesity in African-American children,” CBS News, 5 February 2013, accessed 1 July 2013, http://www.cbsnews.com/8301-204_162-57567780/environmental-contaminants-phthalates-linked-to-obesity-in-african-american-children/; Ted Schettler, “Phthalate Esters and Endocrine Disruption,” Science and Environmental Health Network, accessed 1 July 2013, http://www.sehn.org/Endocrine_Disruption.html. Many phthalate compounds have recently been banned in children’s toys because of the particular threat that they pose to developing bodies.
 See: Occupational Safety and Health Administration (OSHA), Indoor Air Quality and Environmental Protection Agency (EPA), An Office Building Occupants Guide to Indoor Air Quality
 See US Consumer Product Safety Commission on phthalates: http://www.cpsc.gov/phthalates. Phthalates and plastics in personal care products also cause serious environmental harm. See, for instance: Christopher Johnston, “Micro Plastics in Personal Grooming Products Harming The Great Lakes, Researchers Say,” HuffPost Green, 29 June 2013, accessed 1 July 2013, http://www.huffingtonpost.com/2013/06/29/micro-plastics-great-lakes-personal-grooming-product_n_3505323.html?ncid=edlinkusaolp00000003.
 For more information, see EPA on improving indoor air quality: http://www.epa.gov/iaq/is-imprv.html
 Michael Holcomb, “What tests can I do myself to check how healthy my home is?” Green Home Guide. Accessed 25 June 2013. http://greenhomeguide.com/askapro/question/what-tests-can-i-do-myself-to-check-how-healthy-my-home-is
 Julie Scelfo, Raising Concerns About Chemicals in Recycled Carpet Padding, New York Times, 18 May 2011, accessed 25 June 2013, http://www.nytimes.com/2011/05/19/garden/tests-on-carpet-padding-show-toxins.html