Secondhand smoke and the health risks it presents to children is a topic commonly discussed during anticipatory guidance. Recently, I was confronted with a child in the emergency department with an asthma exacerbation and inquisitive parents. I asked my standard litany of social history questions and prepared to discuss the importance of not smoking with the parents. The parents said they were not smokers and allowed no smoking in the home. Furthermore, they had no pets and were meticulous about cleaning their home. They voiced concerns about the potential for their son's asthma to be related to something in their home. I agreed, but found myself with little knowledge to help them sort through the possibilities.
During the past 20 years, a large body of research has documented that indoor air can be significantly more polluted than outdoor air.1 Most children spend 90% of their time indoors, therefore, there are substantial health risks to children from exposure to indoor air pollution. Poor indoor air quality (IAQ) can significantly affect the young and the chronically ill, especially those suffering from respiratory or cardiovascular diseases.2 It may result in aggravated allergies, asthma, sick building syndrome, cancer, and even death.3
TIPS FOR HOMEOWNERS
As new homes are increasingly built to be more energy efficient, indoor air pollution has surfaced as a health concern. Energy-efficient homes result in less movement of outside air into the home and increase the concentration of indoor air pollutants if a proper ventilation system is not installed. Responsibility for controlling the indoor environment falls on the shoulders of the inhabitants, yet homeowners are given little guidance about how to prevent diseases associated with indoor air pollution.
There are multiple solutions to improve and ensure the quality of indoor air.4·5 The solutions fall into three main categories: controlling the source, ventilation, and air filtration (Table, see page 472). Controlling the source involves a wide range of measures, some of which include cleaning the home on a regular basis, minimizing exposure, and reducing quantities of known indoor air pollutants.6 Annual inspections of the heating, ventilation, and air conditioning equipment help prevent leaks and excess moisture in the ductwork that can influence IAQ. Poor ventilation is suspected to be responsible for up to 60% of IAQ problems.1 Increased ventilation may be achieved by simply opening windows and doors, especially when using potentially toxic substances. The last major solution to improve air quality involves installing a whole-house filtration system. This will reduce air pollutants and should be inspected periodically.
Tips on Improving Indoor Air Quality
INDOOR AIR QUALITY LEGISLATION
Legislative bodies pay scant attention to the quality of indoor environments, especially in homes. Most states do not have residential construction codes for indoor air quality that would necessitate ventilation systems to reduce IAQ problems. However, there is a burgeoning national movement led by Energy Star (http://www.energystar.gov) and the US Green Building Council (http://www.usgbc.org) that strives to protect the environment and improve IAQ.
The poor track record of federal and state legislatures at addressing residential air quality issues is disconcerting. For example, Wisconsin Code 21.05 requires that a home have "natural ventilation," meaning the home must have "openable" windows, skylights, and doors that meet a minimal net floor area of the home.7 If the home does not satisfy this requirement, it must have a form of mechanical ventilation that provides at least one air change per hour. There are no other requirements regarding indoor air quality.
The problem with current legislation is that it does not ensure high standards for IAQ. Installing an "openable" window does not guarantee that the home is appropriately ventilated. During a Wisconsin winter, it is doubtful that homeowners will open their windows to introduce fresh air into their home. Also, if fresh air is introduced, it is done so during isolated events, and the home does not get sufficient air changes during the day without a proper ventilation system.
It is important for state legislatures to recognize the importance of IAQ, and enact sound codes to direct thoughtful building practices. Presently, a number of pieces of IAQ-related legislation are being considered by state legislatures. A majority of these are nonresidential in scope.8 Pediatricians and others who care for children should work with elected representatives to formulate and implement sound public-health-based codes.
1. Spaul WA. Building-related factors to consider in indoor air quality evaluations. J Allergy Clin Immunol. 1994:94(2 Pt 2):385-389.
2. Brooks SM. Host susceptibility to indoor air pollution. J Allergy Clin Immunol. 1994;94(2 Pt 2):344-351.
3. Etzel RA. The "fatal four" indoor air pollutants. Pediatr Ann. 2000;29(6): 344-350.
4. Parrott K. Home*A*Syst: An Environmental Risk-assessment Guide for the Home. Ithaca, NY: Northeast Regional Agricultural Engineering Service: 1997:85-5:85-95.
5. Fact Sheet: Ventilation and Air Quality in Offices. Washington, DC: US Environmental Protection Agency, Office of Air and Radiation; 2000. Available at: http://www.epa.gov/iedwebO0/pubs/ ventilat.html. Accessed June 2, 2004.
6. Energy Star. Available at: http://www. energystar.gov/index.cfm?c=new_homes. hm_index. Accessed June 7, 2004.
7. Wisconsin Department of Commerce. Safety and Buildings Division - Administrative Codes List. Available at: http://www.commerce.state.wi.us/SB/SBDivCodesListing.html. Accessed June 7, 2004.
8. IAQ State Legislation: 2004 In Step With 2003; School, Public Building IAQ, Mold Remain Hot Topics. Marietta, GA: Aeri as AQS IAQ Resource Center; March 2004. Available at: http://www.ncsl.org/programs/ESNR/ cehdbhtm. Accessed June 7, 2004.
Tips on Improving Indoor Air Quality