A Comparison of indoor environmental parameters related to ventilation and air-conditioning systems in an old and new wing of a Rural Referral Hospital and its possible effect on disease transmission.
Michelle Bolte1, Alastair Bell2, Alfredo Milaor3, Arun Babu4, Sarah McDonald51HNE Tamworth Rural Referral Hospital, Tamworth, NSW, Australia2HNE Tamworth Rural Referral Hospital, Tamworth, NSW, Australia3HNE Tamworth Rural Referral Hospital, Tamworth, NSW, Australia4HNE Tamworth Rural Referral Hospital, Tamworth, NSW, Australia5HNE Tamworth Rural Referral Hospital, Tamworth, NSW, Australia
It was noted older hospital units, built 50 years ago, experienced further spread of viral illnesses, COVID and Influenza, during outbreaks than wards that were built in the last 15 years. Airborne disease transmission on patient outcomes can be linked to several parameters including indoor air temperature, relative humidity, and indoor air ventilation. The multi-disciplinary hospital team examined the layout of the ventilation systems, and air flow to distinguish if the ventilation system contributed to the spread of disease in older hospital units.
Temperature, humidity, Co2 and air velocity from the intake and extraction vents were measured in old and new wards to compare conditions. Air flow throughout the wards was measured using white smoke. The HVAC dampers were inspected to determine the degree of fresh air being circulated.
Investigations revealed that the older wards had recycled air conditioning systems during the time of the outbreak with the new set as 100% fresh air and this correlated to a difference in Co2 levels. Air flow was positive pressure in both wards, with air movement increasing with staff movement in the older buildings along corridors. Some extraction vents were found inactive.
Results of the study have shown a positive correlation with increased infection rates in older wards when comparing differences in parameters relating to indoor environment (air flow, humidity, Co2, temp). Parameter differences were due to the age of the HVAC systems in each unit. Knowing the parameters of ventilation systems informs plans for appropriate placement of patients with infectious disease.
Biography
Infection Prevention Nurse Consultant Tamworth Rural Referral Hospital for past 8 years. Previous experience includes primary health nurse surgical, wound care specialist and orthopaedics CNS.
Currently mentoring Infection Prevention Link nurses in quality improvement projects and research.