Abstract
Due to the increased number of worshippers in and around Muslim holy mosques, portion of worshippers perform their rituals such as prayers in open spaces surrounding mosque buildings which are usually vented and air-conditioned. In this paper the thermal comfort of worshippers in piazzas of the holy mosques is evaluated using different thermal comfort indices such as the heat index HI, the wet bulb globe temperature (WBGT), the physiological equivalent temperature (PET) and the predicted mean vote (PMV). Hourly weather data for Makkah, Madinah and AlQuds were used to evaluate the thermal comfort conditions. A MATLAB code was written to evaluate the hourly natural wet bulb temperature and globe temperature in order to calculate the hourly WBGT. The hourly weather data were also used with RayMan software to predict PET and PMV. Focus times were 13, 16 and 19 h which are approximately
Dhur
,
Asr
and
Magrib
prayer times. Overall, using different thermal comfort indices it was found that the outdoor condition which is closer to thermal comfort is in AlQuds, followed by Madinah and then Makkah. Several appropriate strategies were suggested for each city in order to bring the environment closer to human thermal comfort level. The study suggests shading piazzas and open spaces leading to the mosques have strong favorable impact on human thermal comfort. Madinah weather in particular is very much appropriate to utilize evaporative cooling (mist system) to provide thermal comfort in and outside buildings economically.