Decreasing inhaled contaminant dose of a factory worker through a hybrid Emergency Ventilation System: Performance evaluation in worst-case scenario

Air pollution is detrimental to human health, causing several human illnesses. The industrial microenvironment generates high levels of indoor airborne pollutants, becoming a pervasive issue for workers. It is essential to improve the indoor air quality in this workplace by applying enhanced ventilation systems to minimize inhalation risk. Displacement ventilation is used in industrial buildings because of its stratified air distribution and low cost. However, in case of accidental pollutant release, an enhancement is needed to minimize inhalation exposure. This study proposes a hybrid emergency ventilation system using localized push-pull ventilation to improve the installed displacement ventilation system of a representative workshop. Computational fluid dynamics was applied to calculate steady-state indoor air flow and volume-averaged pollutant concentration. System performance was evaluated in terms of source position; a computer simulated person was integrated to the building to confirm effectiveness against personal inhalation. Results showed marked improvement in performance when push-pull technique was used: room-averaged concentration diminished up to 91% while ventilation rate only increased 4%. Inhaled pollutant mitigation was achieved but performance dependence against leakage source and personal position was confirmed.