Effect of environmental parameters on culturability and viability of dust accumulated fungi in different HVAC segments

Abstract

Fungal contamination in dust accumulated on inner surface of the heating, ventilating, and air-conditioning (HVAC) systems has closely association with indoor human health. Dust samples were collected from 24 central HVAC system installed in office buildings in Beijing, China. The purpose of this paper is to investigate the distribution of fungal spore, culturable and viable fungi loading in five HVAC segments including the segments of fresh air, return air, mixture air, cooling and supply air. Fungal culturability and viability in dust samples collected from each sampling site were calculated and compared. The effects of environmental parameters and deposition dust loading on fungal concentrations, fungal culturability and viability were investigated by the Pearson correlation. In addition, predominant fungal species in deposition dust accumulation were identified, and its occurrence rates and relative abundances were also determined. These results could provide some useful information for fungal contamination control in HVAC system.