Optimal operating positions of two air purifiers for improving indoor air quality in hospital wards

Background: Maintaining high indoor air quality (IAQ) in hospital wards is crucial, particularly in settings lacking proper ventilation. This study investigates the effectiveness of air purifiers in enhancing IAQ under varying conditions, including ventilation systems and curtains. Aim: This study aims to evaluate the optimal operating positions of two air purifiers to enhance IAQ in hospital wards under varying ventilation and curtain use conditions. Methods: This study employed a combination of experiments and computational fluid dynamics (CFD) simulations across 20 scenarios, analysing the impact of air purifier placement on the age of air, a key IAQ metric. Findings: This study found that the positioning of air purifiers greatly influenced IAQ, with reductions in the age of air ranging from 19% to 44% depending on the configuration. The most effective placement involved active ventilation systems and unfolded curtains, leading to a significant decrease in the volume-averaged age of air. Conclusion: This study concludes that optimal placement of air purifiers in hospital wards can significantly improve IAQ, with reductions in the age of air by up to 44%. Specifically, when ventilation systems were active and curtains were unfolded, the age of air was reduced to as low as 318 s, representing a 27–44% improvement over less-effective configurations. These findings emphasize the critical role of strategic air purifier placement in reducing airborne infection risks and enhancing patient safety in healthcare environments.