Mid-semester break: Influencing factors of indoor air quality

Source: Google image, 2016

According to the definition of the World Health Organization (WHO) in 1983, sick building syndrome is symptoms arising due to the use of buildings, including the red eyes, a runny nose, sore throat, drowsiness, headache, nausea, dizziness, skin itching. In recent years, some experts and scholars have suggested that people's dissatisfaction with the indoor smell is also incorporated into the sick building syndrome. A large number of survey and analysis show that people have about 90% of the time spent indoors, poor indoor air quality is the main cause of sick building syndrome. Influencing factors of indoor air quality are list below.

1.     Indoor pollution source   

Indoor pollution can be divided into five categories: First one is the particles of pollutants, including from the various bedroom supplies or biological dust, short fibers and hair; The second one is building decoration materials, coatings and household chemicals release of VOCs (volatile organic compounds), such as formaldehyde, benzene etc. The third category is biological pollutants, including the metabolites of bacteria, fungi, viruses from decaying matter and pet. They will make the weak resistance people infected. In addition, pollen and dust mites will trigger allergic reactions in allergy crowd; the fourth category is the radioactive material, which can directly induce cancer and it is sourced from bricks, mortar materials, soil etc. The fifth category is the human body's pollution, including the body odor，a small number of patients access to public places and cross infection through the air. These pollution sources will have a bad effect on IAQ. 

2. Outdoor pollution source

The outdoor pollution sources mainly include the nitrogen oxides in the exhaust gas, the SO2, CO and the particulate matter excluded by the industrial and civil boiler.

3. Air conditioning system

Air conditioning system equipment is also easy to become a source of pollution. For example, in table cooler cooling humidity reduction process, the water collecting disk is extremely easy to breed bacteria; filter have dust and micro-organisms, if not timely replacement, is extremely easy to become a major pollution source.

Reference List:

Wenku.baidu.com. (2011). Influence factors and improvement measures of indoor air quality. [online] Available at: http://wenku.baidu.com/view/4fbbe027ccbff121dd368325.html?from=search [Accessed 2 Apr. 2016].

Wenku.baidu.com. (2012). Several factors affecting the indoor air quality. [online] Available at: http://wenku.baidu.com/view/391f38d476eeaeaad1f330ef.html?from=search [Accessed 9 May 2016].