Best approaches for maintaining indoor air quality
Managing indoor air quality (IAQ) in long-term care facilities is a serious and somewhat complicated business. Older adults are more susceptible than younger people to the effects of airborne pollutants and may develop conditions including but not limited to asthma, chronic obstructive pulmonary disease (COPD) and even cancer when exposed to typical contaminants in nursing homes and assisted-living settings over long periods.
Polluted indoor air is a cocktail with many possible ingredients. Dust and mold spores are frequent contributors. Smoke particulates from cooking and burning candles often pollute indoor air. Volatile organic compounds (VOCs) given off by building materials, paints, adhesives and furnishings are among the most dangerous and difficult pollutants to control. Common IAQ complaints also include the presence of unpleasant odors and air that is too humid or too dry.
Ed Bes, the author of Indoor Air Quality: A Guide for Facility Managers, writes: “IAQ problems range from the simple to the complex, and there are as many solutions as there are causes. Many IAQ problems boil down to the HVAC system's design failing to meet current needs, or due to improper HVAC operation and maintenance.”
A document called ANSI/ASHRAE/ASHE Standard 170, Ventilation of Health Care Facilities, sets the most recent minimum guidelines for the design and performance of heating, air-conditioning and ventilation systems to address indoor air quality concerns. If your facility seems to have a serious IAQ problem or are planning a major renovation, the specifying engineers will surely consult it. But some issues, including dust control, lingering odors and VOC contamination, may be addressed by using one or more advanced air filters and/or standalone air purifiers.
In many applications, high-efficiency particulate-arresting (HEPA) filters, which are designed to capture particles with a diameter as small as 0.3 microns, are adequate for controlling dust and pollen in indoor air. But standard HEPA filters cannot capture VOCs, nor are they suited for controlling odors.
To remove odors and chemically reactive gases, HEPA air purifiers combine HEPA technology with additional filtration systems, including carbon and potassium iodide media. Charged media filters use static electricity to attract and trap airborne particles as small as 0.1 micron.
In addition to choosing the appropriate type of filter for the contaminants at a given site, the American Society of Healthcare Engineers (ASHE) recommends that filters applied in resident care, treatment and support areas in assisted living facilities have a minimum efficiency reporting value (MERV) rating of at least seven. MERV ratings are accurate predictors of filter efficiency over time. ASHE also recommends that HEPA filters installed in healthcare environments be subjected to a dispersed oil particulate (DOP)/photometer test to determine that they are performing as advertised.
Filtration performance may affect indoor air quality in several ways. Poorly maintained filters with inadequate seals and breaches allow contaminants to flow into spaces where they can do harm. When filters aren't changed on the schedule recommended by the manufacturer, they can become blocked, compromising airflow and the performance of the heating and cooling system.
Addressing facility managers, Bes writes, “Our goal in ensuring quality indoor air is to provide a healthy, pleasant indoor environment where people are comfortable and productive. Failure to properly address these problems, however—particularly when the environment may be the cause of health complaints—runs the risk of lawsuits, poor public image, poor tenant relations and lost tenants... The good news is that a healthy building is not one that is very difficult to attain nor is it necessarily one that is more expensive to run.”
Michael Chotiner has many years of experience as a construction general contractor on both commercial facilities and residential structures. Learn more at Home Depot's website.