An Investigation of an Affordable Ventilation Retrofit to Improve the Indoor Air Quality in Australian Aged Care Homes

Residents in aged care homes constitute a significant proportion of Australia's population. The elderly population is vulnerable to poor indoor air quality (IAQ). Because mobility declines with age, they tend to spend longer indoors compared with the general population. This study evaluated the effectiveness of an affordable ventilation retrofit to improve the IAQ in aged care homes in Victoria, Australia. The fresh filtered air ventilation system was installed independently of the existing heating, ventilation, and air conditioning (HVAC) system in each facility. The monitoring characterized the ventilation of aged care homes to establish the baseline performance. The results showed that air change rates (ACH) in the common rooms were from 0.84 ACH to 3.81 ACH. This was generally sufficient for low or average occupancy but insufficient when the rooms were fully occupied. Up to a 1,000 ppm reduction in the carbon dioxide (CO2) concentration was achieved with the addition of a supplementary ventilation system. However, there was no reduction in the levels of particulate matter (PM). Local activities and the movement of people inside the room influenced the PM concentration. A systematic approach for the regular monitoring of IAQ, analyzing data, and adopting appropriate interventions is required to better prepare the community and the health systems against the consequences of climate change.