Outdoor air pollution is an essential contributor to indoor air pollution -- but high-efficiency particulate air (HEPA) filters used in the house significantly diminish tiny-particles in the atmosphere in comparison with non-HEPA air filters, a new study shows.
Researchers observed air quality for three months at the houses of registered patients who had respiratory problems. They discovered that the HEPA filters decreased fine particulate matter by 55 percent and particulate pollution outside coming indoors was reduced by 23 percent.
Fine-particulate matter, also referred to as PM2.5, is a term used to describe small airborne particles frequently found in areas with substantial air pollution levels.
The size of PM2.5 particles is approximately 3% of the diameter of a piece of human hair. When inhaled, they may result in respiratory problems, heart attacks or aggravate symptoms of individuals who are already suffering from problems like chronic obstructive pulmonary disease or asthma.
During the winter in Utah, temperature inversions trap dirty cold air inside the Salt Lake Valley -- that gives Utah some of the worst air in the nation. Within the home, researchers analyzed the efficiency of HEPA filters during these inversions.
"One reason we desired to examine the efficiency of HEPA air filters in the house is that we frequently ask what they can do to protect their lungs through poor air quality days," said Denitza Blake, MD, Pulmonary Researcher at Intermountain Medical Center in Salt Lake City.
"We discovered that running a standalone in-home HEPA filter and using the windows at the house closed can provide cleaner air inside the house, especially when outside air is so bad."
Results of this analysis were presented on Sept. 16th during the European Respiratory Society's International Congress in Paris.
Information from 30 associates enlisted in the study revealed that when HEPA filters were employed during winter inversion months, only five percent of outside air PM2.5 contributed to the indoor air quality, in comparison to 28 percent when HEPA filters were not being used.
Throughout the 12-week study, which happened during the winter inversions of 2017 and 2016, air filters were replaced in 52 Utah homes. There has been a HEPA filter used for the first six-week period, and another low-efficiency air filter has been used during the 2nd six-week period. The research participants were not aware of which filter was used during each period.
Each player's house was outfitted with two inexpensive air quality monitors. One was placed outside the home, and another was set indoors. Differences in the quality of outdoor and indoor air were compared throughout the study interval.
Dr. Blake said, “Our next steps are to look at if the HEPA filter refines the indoor atmosphere sufficient to help ease signs in patients with COPD or asthma through poor air quality days." "We often encourage our patients with respiratory disorders to remain inside on days when PM2.5 is high outside, but we hope to identify ways to help improve the indoor air quality and alleviate symptoms in our patients, which will protect our lungs from harmful air pollutants."
Dr. Blake worries that while the HEPA filters decrease PM2.5 inside the house, everybody should make efforts to enhance the general outdoor air quality in their associations.
Some other members of the Intermountain Medical Center team include Benjamin Horne, Ph.D., Danielle Babbel, and Daniel Bride; and Daniel Mendoza, Ph.D., from the University of Utah.
Intermountain Medical Center is the flagship clinic for the Intermountain Healthcare system.