Thermal Comfort

Most people feel comfortable when they have neither sensations of heat or cold. The zone in the middle between ‘hot/warm’ and ‘cool/cold’ is termed a thermally ‘neutral’ zone or ‘comfort’ zone.

The intensity of the sensation of feeling hot or cold or amount of actual heat lost or gained is directly proportional to the temperature differential between a person’s body temperature (37 deg C) and the air or surfaces the person is exposed to.

It is important to understand that thermal comfort is highly subjective as it is the net perceived result of a combination of physical and psychological factors such as age, acclimatisation, gender, health, physical activity, clothing and other factors.

Heat balance between a person and their environment is primarily dependent on air temperature, radiant heat, humidity and air flow which in turn are effected by thickness of clothing, activity level and acclimatisation.

CSIRO Simplified Climate Zones

Australia covers a large range of latitude and hence displays a wide range of climates although most of the population resides in the temperate regions. Commonwealth Scientific & Industrial Research Organisation (CSIRO) has therefor divided Australia into eight simplified regions based on historical records of temperature and humidity and it is these regions that are used in projects to achieve compliance using the prescriptive “Deemed To Satisfy” (DTS) provisions of the BCA.