According to a new research, the content of interior air could affect health and comfort of building occupants.
Recent findings have demonstrated that indoor air is often more polluted than outdoor air although this has not changed the common understanding of air pollution. In fact, indoor air is often a greater health hazard than the corresponding outdoor setting. Using ventilation to dilute contaminants, filtration, and source control are the primary methods for improving indoor air quality in most buildings.
The researchers studied the efficacy of high efficiency particle air (HEPA) filters. It turned out that these filters significantly improve cardiovascular function in healthy, nonsmoking elderly individuals.
HEPA filters can remove at least 99.97% of airborne particles 0.3 micrometers (µm) in diameter. Particles of this size are the most difficult to filter and are thus considered the most penetrating particle size (MPPS).
21 nonsmoking couples, aged 60 to 75, living close to heavily trafficked roads took part in this research. Each couple used air purifiers for two 48-hour periods. During one period, the purifier was equipped with a HEPA filter, and during the other, it ran without it. The size distribution and number concentration of indoor air particles in each home were registered.
The results surprised the scientists who expected to get worse results by usage of HEPA filters.