In situ tests about removal performance of airborne microbe particles by an air filter

The performance of a particulate air filter is mostly based on the filtration efficiency obtained by weight method (for CPA filter) or dust spot method (for MEPA filter). The primary goal of this study was to obtain the filtration efficiency over airborne microbes of a CPA filter or MEPA filter which are normally installed in Japanese office buildings. In-situ tests were carried out on three air-handling units and one package air-conditioner located in Tokyo. Suspended particle and airborne microbe concentrations at both upstream and downstream sides of the test filter were simultaneously measured under the real operating conditions. The results are presented.