Indoor Environmental Quality Audit and Investigation of Ceiling Fans in an Aged Care Facility

This thesis project involved research into the thermal comfort of the occupants and staff at the Warrigal aged care facility at Warilla, NSW, Australia. An Indoor Environmental Quality (IEQ) Audit has been completed with a focus on parameters of luminance, noise levels, concentrations of CO2, NO2, formaldehyde and CO, and air velocity. An extensive investigation of the distribution of indoor air temperature and relative humidity has been performed. Small sensors called ‘iButtons’ were installed to record the relative humidity and air temperature every 15-minutes in many locations throughout the facility. It is important to note that the main occupants of Warilla aged care facility suffer from dementia, were bed-ridden elderly people or otherwise healthy older adults. It is thought that sensations of feeling comfortable in the indoor environment are perceived differently by elderly people and especially by dementia patients. This thesis work primarily focussed on the thermal comfort of adults with an emphasis on elderly and dementia patients. The results of the IEQ audit have been compared with recognised standards e.g. AHSRAE ADDENDA 62.1, ASHRAE 55, EN 15251, EN 12464, ISO 7730 and ISO/TS 14415. Furthermore, this thesis project involved the development of a CFD model to predict the airflow induced by ceiling fans in an indoor environment. Such ceiling fans were installed in the Warilla aged care facility as a result of a previous audit, and it was thought that these might have resulted in uncomfortable air temperatures in the bedrooms and dining rooms. Since the ceiling fans can assist in controlling the sensation of thermal comfort, these were investigated with a model built in ANSYS CFX. To validate the model, experimental measurements were compared with the results of the model, and an agreement was found to be around ±20-35% with the experimental results of measured air velocity of ceiling fans. The outcomes of the report are included in the end of this thesis. The IEQ audit found uncomfortable measures of temperature and humidity, mainly in the summer and spring seasons. In addition, the CFD modelling resulted in the performance of ceiling fans and the air velocities induced by it in relation to thermal comfort, which were outside of the thermal comfort criteria discussed in Chapter 3 (ASHRAE 55, 2013)