Review of Health Aspects in Buildings as pertain to VOCs and Clay Brick Masonry Walling
Introduction to Indoor Air Quality (IAQ)
As people spend approximately 80-90% of their lifetime indoors, the health and physical well-being of building occupants is therefore important, particularly for the young and the aged. Harmful chemical substances in the indoor air, dust and mould spores, high levels of carbon dioxide, cigarette smoke, and odours from cooking or cleaning detergents can lead to long term health problems. Furthermore, the use of certain building materials, furniture or floorings can be responsible for toxic emissions, which compromise Indoor Air Quality.
The aspect of room temperature (local comfort conditions varying between 19-26°C) and humidity (40-60%) is also essential for human wellbeing, and has a bearing on energy usage for artificial heating or cooling.
The reduction of heating and cooling demand and the improvement of energy efficiency of buildings has recently become a goal of new buildings in South Africa. Architects are also increasingly focusing on a holistic integrated approach to healthy living, including air quality - an area that was previously the preserve of mechanical engineers. For building occupants, energy efficient living does not constitute a dominant priority, but the quality of living represents their main priority.
Other aspects to indoor air quality include asbestos fibres, biological pollutants, carbon monoxide, formaldehyde (in the main from particle-board), lead, nitrogen dioxide, pesticides, radon, respirable particles, second hand smoke, including tobacco smoke, and emissions from stoves, heaters, fireplaces, and chimneys, spores derived from mould growth and Volatile Organic Compounds (VOCs).
“Sick Building Syndrome” describes the situation which is derived from poor indoor air quality and is diagnosed when several persons living or working in the same building complain of similar symptoms of illness such as irritations of conjunctiva, nasal and throat mucous membranes, reddening, itching, sneezing, headaches, dizziness and tiredness. Furthermore, hypersensitivity or allergy-increasing characteristics, particularly carcinogenic, mutagenic or toxic for reproduction properties may lead to long-term effects. The “Sick Building Syndrome” applies when the percentage of people showing these symptoms is higher than that in comparable buildings.