Generally, bioaerosol is defined as the microorganisms forming or particles, gases, vapours or fragments of biological origin whether it’s alive or released from living organism (PEOSHP, 2003). The components of bioaerosol vary considerably in small tiny size from about 0.02 to 100µm (diameter) (Pillai, 2002). It was released from a wide range of activities or processes and also the presence in the air environment as a single cells or fragments form (Folmsbee M, 1999). Certainly, bioaerosols include a mixture of viable (culturable and non-culturable) and nonviable microorganisms in the environments (Peccia et.al, 2010; Paul et. al., 1998). For example are pollen, algae, bacteria, fungi, yeasts that are as well as antigenic compounds, plant…show more content… In other words, microbial of bioaerosol are almost inevitable in most enclosed environments either it is a presence in the water or liquid form, soil, rocks, solid matter, air, plants, animals and human. Moreover, fungal spores are of major concern in the airborne particulate matter because of their abundant source. The presence of the microorganism in the air is pervasive, whereas their proportion varies according to the environmental conditions and locations. Furthermore, the size of the distribution of bioaerosol actually depends on the type of specific microbial species (Reponen et.al., 1996) how it is actually exposed in the air, the age of the spores and nutrient medium presented (Ellis, 1981) and so on. Besides, both indoor and outdoor environment also have different size distribution and composition of airborne bacterial and fungal. Otherwise, the concentration of bacteria and fungi in bioaerosol are probably due to the meteorological condition in the environments which is depending on such biotic and abiotic…show more content… More than that, microorganism represent in the building is very complex. Microbial damage is most frequently caused by moulds (spores) and bacteria. In the biogeochemical cycle, microorganism certainly plays a very important roles. The biogeochemical cycle can be defined as a task that consists of disintegrating organic mass to reusable metabolites (Yassin, 2009). However, microscopic organism and spore of moulds in the environment may to be the airborne or bioaerosol contaminants in industrial or non-industrial areas. It happens due to their ubiquitous presence in nature, the presence of microorganisms can enter indoors through the heating, passive ventilation and air conditioning system, doors, windows, cracks in the walls, the potable drinking system, or be bought in on the shoes and clothes of people working or exposed to dust or any particles outside building (PEOSHP, 2003). Otherwise, it is also can emit by indoor sources like animals, flowerpots, and wastebaskets. Moreover, poor sanitation aspect, high of population density in the indoor area, due to heavy traffics and unhygienic conditions or environment in the food courts could be the predominant source of microorganisms live and widely growth in the