THIS invention relates to a method and system for purifying or cleansing a gas stream or gaseous body containing one or more contaminants.
It is well established that outdoor air pollution can cause serious human illness. Air pollution can cause burning eyes and noses, itchy irritated throats as well as breathing difficulties. Some chemicals can cause cancer, birth defects, brain and nerve damage, long-term injury to lungs and even premature death. As a result, protection of the public health is a driving force behind the laws and regulations that are being, and have been, put into place to clean up the environment. However, ridding outdoor air toxic contaminants has often overlooked indoor air quality (IAQ).
The results of numerous scientific investigations have revealed many reported outbreaks of what is known as Sick Building Syndrome (SBS) and Building Related Illness (BRI) as a direct result of indoor air pollution (IAP) in office and other public access buildings.
SBS is used to describe the situation in which building occupants experience acute health and comfort defects that are linked to time spent in the building. BRI is the term used when diagnosable illness and symptoms are identified and directly attributed to airborne building material contaminants.
In modern society, it is believed that most people spend as much as 90% of their time indoors. The US Environmental Protection Agency (EPA) has indicated that IAP may be between 2–5 times higher than accepted levels, and up to 100 times higher than outdoor pollution levels.
The World Health Organisation (WHO) Committee Report on IAQ suggested that 30% of new and re-modelled buildings globally are subject to excessive complaints of IAQ and have unusually high rates of SBS and/or BRI. For example, according to the SA Singapore embassy, 92% of all absenteeism in Singapore can be attributed to SBS and/or BRI.
IAQ is rated within the top 5 of the US EPA's most critical global concerns alongside ozone depletion, global warming and the like. It has been reported, for instance, that in 1989, the US economy suffered a staggering US $65 bn loss due to SBS and BRI. The absenteeism levels, due to poor health caused by IAP, resulted In this huge productivity decrease.