Microbial in Buildings
The evolution of microbes and its impact is not yet a very well explored area. However, lately, microbes are found causing Building Related Illness (BRI) and Sick Building Syndrome (SBS). BRIs are health issues a person acquires in a building and suffers from it even after leaving the occupancy. As more number of people are spending time indoors, the study of microbes as a potential IAQ problem is gaining prominence.
According to the “WHO Guidelines for Indoor Air Quality: Dampness and Mold”, microbial pollution is a key element of indoor air pollution. It is caused by the presence of bacteria, viruses and fungi, in particular, filamentous fungi (mould). These grow indoors when sufficient moisture is available.
To avoid adverse health effects, persistent dampness and microbial growth on interior surfaces and in building structures must be prevented.
Exposure to these microbial pollutants causes respiratory symptoms, allergies, asthma and immunological reactions.
Microbial Contaminants and its adverse effects
Humidity-rich air can create a healthy breeding ground for microbial contaminants. Microbes breed fast in dampness and inadequate ventilation. This can lead to emit spores, cells, fragments and volatile organic compounds into indoor air. Dampness indoors can be causing asthma and respiratory symptoms e.g. cough and wheeze. Some microorganisms, such as bacteria and fungi, multiply more rapidly in high humidity.
Hazards are also posed by several biological agents that pollute indoor air. It estimated that millions of skin scales are shed per minute per person. This is with an average of four viable bacteria per scale. Evidently, viruses that infect humans can be transmitted by the air.
Legionnaires disease is a fatal lung infection, caused by microbes from sources such as cooling towers. The disease spreads from contaminated air-cooling equipment producing concentrated bacterial aerosols. A less severe form of the disease from the same microorganism, known as “Pontiac fever,” causes fever, headache, muscle pain, and malaise. Hot tubs, whirlpools, and by air conditioning and humidifying equipment can disseminate similar disease-causing microorganisms. Cool-mist vaporizers and nebulizer are contaminated with bacteria and can produce highly contaminated airborne droplets.
