2.5.2. Exposure assessment

To assess the potential levels of exposure of people and workers to RoV and NoV in the air of water spray park, the daily inhalation was calculated according to Eq. (1) [23]:

where D_e refers the exposure dose (GC.day⁻¹), C denotes virus concentration (GC/m³), ET_inhalation represents the exposure duration (h), and IR is inhalation rate (0.83 m³/h). The time of exposure for people refereeing to Laleh park and employee were considered 1.5 and 8 h, respectively. In addition, the background concentration levels of two pathogenic viruses (RoV and NoV) were considered zero, denoting assumption of these pathogenic viruses in ambient air away from any pollution sources. Furthermore, a simplified approaches without ages of people and susceptibility equal to 1 was considered to represent the worst-case estimation which is advisable in QMRA [35].