ABSTRACT
This chapter describes the elements of indoor environmental quality which should be satisfied in all energy-efficient buildings to provide a healthy and comfortable environment for occupants. The combination of the four elements is usually referred to as indoor environmental quality, which impacts the health and wellbeing of occupants. The four elements are: thermal, visual, acoustical and air quality. Indoor air quality (IAQ) has increased in importance and at the centre of considerations in the design of building services at equal terms with energy efficiency. In order to maintain acceptable IAQ in buildings, sensors are used to control the ventilation rates of heating, ventilation and air conditioning systems or actuators in natural ventilation systems to provide additional ventilation should the sensed parameter be above recommended guidelines. Thermal comfort provision is as complicated as IAQ provision because human thermal comfort is influenced by a number of parameters, which in turn are influenced by external climatic conditions, construction of the building and solar and internal heat gains.
