Indoor air quality refers to the aerosol and gas content, temperature, and humidity of the air inside a structure. In the case of human habitation, the quality of the air is determined by its ability to maintain the health and well-being of humans occupying the structure. In the case of manufacturing processes, the quality of air is determined by the ability to cost-effectively produce high quality products inside the structure.
The most important part of indoor Air quality is the cleanliness of the air. Air contamination consist of particles, gases and vapours that may reduce the well-being and health of humans and decrese the output and efficiency of production processes.
IAQ in production processes
The IAQ industry has generally specific demands for good cleanliness level in terms of particles and molecular contaminants. The requirements are normally ranging from good hygienic levels with low levels of contamination to extreme high cleanliness levels (for example the semiconductor industry).
Human health
The health and well-being of humans are affected by air contamination. Research about the importance of clean indoor air has been intensified the recent years. Today there are clear indications on that particles (especially fine- and ultrafine particles) can cause problems, both in the short term and long term perspective. Gases and vapour can cause irritation or even acute problems depending on the concentration levels. Typical examples of those gaseous contaminants are Ozone, NO2 and VOC (Volatile Organic Compounds).
Read more about the different sources that cause poor indoor air quality and what symptoms that may occur.
Sources
Symptoms
Why has indoor air quality declined?
During the 1970s, the global use of energy became an important political and economic topic due to the energy crises that took place in that decade. Subsequently, the cost of heating and cooling of air in buildings increased and changes in construction techniques took place. Many buildings were retrofitted with insulation, vapour barriers and new, tighter windows and doors. New building construction techniques were developed to decrease the amount of heat transfer through walls and windows and reduce the volume of air infiltration or exchange through walls, windows and doors. As a result, the buildup of contaminants and moisture inside buildings that had previously provided a healthy environment became an issue.
Sick Building Syndrome is now a common label used for headaches, eye irritations, nasal irritations, fatigue and other symptoms that can be correlated to time spent inside a specific building or room.
Building Related Illness refers to a specific diagnosable illness whose cause can be traced to a particular building or room. Legionnaire's disease is an example of a Building Related Illness.