Indoor air pollution is a very real and dangerous thing because indoor air is far more concentrated with pollutants than outdoor air. Indoor air pollution has a far greater impact on developing countries than it does on developed ones because fuel, such as wood, charcoal and animal dung, is burned inside homes for cooking and heating. Rarely is there proper ventilation to allow the pollutants to escape, so residents of these homes end up breathing in carbon monoxide and other dangerous contaminants.
Indoor air pollutants from indoor fuel burning lead to serious human health problems, such as pneumonia, bronchitis, cancer, heart disease and asthma. And, since more than half of the population of developing nations has no other method for cooking and heating, it's not surprising that indoor air pollution from indoor fuel burning kills 1.6 million people each year.
Commonly HVAC systems control the ambient environment (temperature, humidity, air flow, and air filtering) and must be planned for and operated along with other data center components such as computing hardware, cabling, data storage, fire protection, physical security systems and power in IT industry, similarly for Hospital ICU, NICU, OT and in Pharma (Clean room) or Drugs manufacturing area or In chemical / hazardous places.
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