液体状粒子負荷試験におけるHEPAフイルタ性能の経時変化

抄録

The time dependency of filter performance across a high-efficiency particulate air (HEPA) filter was experimentally studied. The experimental study was carried out using a HEPA filter (203×203×150mm) clogged with liquid particles (mosquito stick aerosol). The aerosol concentration for filter loading was 0.84mg/m³ and the size distribution was similar to lognormal distribution (CMD=0.21μm, δg=1.65). The mass loading was about 60g/m² when the pressure drop across the HEPA filter reached twice the initial pressure drop. The DOP particle penetrations through the HEPA filter were evaluated when relative pressure drops (ΔP/ΔP₀) were nearly 1.0, 1.3, 1.4, 1.6, 1.8 and 2.1. The most penetrating particle size (MPPS) was almost independent of the mass loading if the face velocity was constant. However, the DOP particle penetration increased remarkably with mass loading, and the tendency of increase was not affected by particle size or face velocity.