Investigation on the performance of airliner cabin air filter throughout the lifetime usage

The supply air from the airliner ventilation system is a mixture of outside air and recirculated air that passes through a high efficiency particulate air (HEPA) filter. The effectiveness of two commercial-available airliner cabin air filters were investigated under the laboratory-based measurement due to the practical restriction of airliner cabin filter test during usage. The filtration efficiency and pressure drop were assessed at particle size range of 20-500 nm under various airflow rates throughout the filter usage period. The Most Penetrating Particle Sizes (MPPS) were observed at ~150 and ~55 nm, where the filtration efficiency was 86% and 99% at the rated airflow rates (1600 m h and 1970m h), respectively. The filtration efficiency decreased in response to the increased airflow rate from 1000 m h to 2200 m h with the greatest reduction (~10%) occurred at MPPS. An increase of 250 Pa pressure drop across the filter was observed as the airflow rate increased from 1000 m h to 2200 m h. The filter usage led to the increases of filtration efficiency and pressure drop. The actual filter usage was estimated using dust loading in the laboratory. Filtration efficiency increased ~10% and pressure drop increased ~800% as 220 g m dust was loaded that corresponds to ~6000 hours filter usage at in-cabin PM10 concentration of 100 μg m. Explicit relationships among filtration efficiency, pressure drop and filter usage under various in-cabin particle concentrations were presented as a reference to facilitate airliner cabin air filter exchange periods.