When more than 20 percent of inhabitants in a building declare that there is poor air quality or have health conditions, there is a chance that they will be facing a Sick Building Syndrome case. Faced with this phenomenon, the affected people present symptoms similar to those of the common cold or those of respiratory diseases. According to the experts, the most frequent causes of building syndrome are insufficient ventilation due to the lack of maintenance, poor distribution and insufficient intake of the fresh air.
Other data suggest that nil or poor mechanical ventilation can cause 50 to 52 percent of the abnormal particles to appear due to the pollution from offices and the cleaning products, in fact, it is estimated that between 17 and 19 percent of the buildings suffer from this type of complications, according to figures from the relevant organizations.
Inadequate air intake or poor filtration can generate 11 percent of the abnormal particles inside, while the transportation of the microbiological contaminants through ventilation ducts, humidification systems, or cooling towers can generate between 5 and 15 percent of the pollutants according to a study.
The indoor air pollution in buildings has resulted in more serious diseases, accompanied by the clear clinical symptoms and clear laboratory results such as hypersensitivity, Pontiac fever legionellosis. However, a common view among the researchers is that these illnesses should be taken as the independent factors of the Sick Building Syndrome for the reason that most of them appear due to the lack of maintenance in air conditioning systems.
The contamination from outside as well as the inside must be considered; there are three main sources as combustion in the stationary resources (the power stations), combustion in mobile sources (the vehicles) and the industrial processes. Five major pollutants are emitted by these sources as carbon monoxide, sulfur oxides, nitrogen, VOCs and polycyclic aromatic hydrocarbons.
For this reason, it is important to properly design the air and ventilation system and that it complies with the architectural specifications of the building because, in addition to reducing the speed with which the air circulates inside the building, the efforts will have to be evaluated to increase its insulation and impermeability of the installation and see, later, if this type of material will not generate sources of the indoor pollution. The work of the sector will be to evaluate the factors and specify the amount of the air to be renewed and the location of the natural air intakes in order to ensure an optimum indoor air quality.