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Three Contributors to Indoor Air Pollution

Three Contributors to Indoor Air Pollution

Indoor air quality investigations have identified the three major contributors to indoor air pollution inside homes, in schools and at workplaces.  They are:

  • Volatile Organic Compounds (VOCs) gases 
  • Biological Contaminants
  • Heating, Ventilating, Air Conditioning (HVAC) systems

Volatile Organic Compounds or VOCs are invisible chemical gases released into the air at room temperature from products made with VOC chemicals.  Many building and decorative products used in homes, schools and workplaces are manufactured from materials containing VOCs, which are released when used and when they are stored.

Formaldehyde (CH2O) is a VOC that is widely used as an ingredient to make other chemicals, building materials, household and personal care products.  It is also a by-product of combustion and is found in second-hand cigarette smoke, automobile exhaust, burning of wood, coal, and charcoal.

In 2004, the International Agency for Research on Cancer (IARC) officially declared Formaldehyde as a known human carcinogen (cancer-causing substance).  Many countries have since then implemented strict laws and regulations to control and lessen the use of formaldehyde.  Products containing formaldehyde include:

  • Wood and Vinyl Flooring
  • Wall Panels and Thermal Insulation
  • Cabinets and Drawers
  • Carpet and Backing
  • Wallpaper and Wallpaper Adhesives
  • Paint and Varnishes
  • Second Hand Cigarette Smoke
  • Exhaust Smoke from Cooking
  • Air Fresheners
  • Scented Candles
  • Dehumidifiers
  • Photocopiers and Printers
  • Mattresses and Curtains
  • Cleaning Products and Waxes
  • Mattresses and Curtains
  • Cosmetics and Perfumes
  • Shampoos and Hair Color Dyes
  • Nail Polish and Remover
  • Deodorizers
  • Ozone Producing Air Cleaners
  • Pesticides and Mothballs
  • Aerosol Spray Paints

Biological Contaminants are extremely small microscopic living and dead organisms that are invisible to the naked eye.  Biological contaminants have been identified as a major source of “Sick Building Syndrome”, infectious diseases, and allergic reactions such as asthma, pneumonitis, rhinitis, allergic sinuses, hypersensitivity and fatigue.

The dusty, damp, dark places inside Heating, Ventilating, Air Conditioning (HVAC) systems, makes it an ideal environment for biological contaminants to quickly grow and multiply, and eventually spread throughout rooms and buildings via the building’s air conditioning system.

Biological contaminants such as mould and fungi, produces mycotoxins, which are toxic to human, causing illnesses such as kidney and liver disease.  Biological contaminants include:

  • Bacteria
  • Microbial (black sticky jelly)
  • Mould
  • Spores from Mould
  • Mildew
  • Cockroaches
  • Animal Dander from Pets
  • Viruses
  • Fungi
  • Yeast
  • Dust Mites
  • Pollen
  • Dead Insect Body Parts
  • Pest Droppings

Heating, Ventilating, Air Conditioning (HVAC) system is the equipment that brings fresh air into buildings and concurrently dilutes pollutants inside by exhausting stale indoor air out of the building. IT also provides cool air in the summer and heat in winter.

Indoor air quality investigations found the HVAC system to be at the heart of almost all indoor air pollution problems.  A properly maintained HVAC system can resolve almost all indoor air pollution problems as well.

Improper maintenance or no maintenance of the HVAC is the ideal breeding place for biological contaminants to quickly grow and multiply, and it becomes the main culprit of indoor air pollution by spreading VOCs and biological contaminants throughout homes, schools and workplaces.

In 2008, the Shanghai Municipal Health Bureau inspected HVAC systems in 699 public buildings and found nearly 80 percent of HVACs have never been cleaned since they were first installed.

“The Shanghai Hotel in Jing’an district was the first hotel in Shanghai to install air conditioners in the 1980s – and it has not been cleaned ever since for the past 20 years.” said Ms Zhou Yanqin, the deputy director of the Inspection Agency (Global Times – May 07, 2012).

Shockingly, the inspection also revealed that more than 40 percent of the HVAC water-cooling towers were infected with the deadly legionella pneumophila bacteria, that causes the Legionnaires’ Disease, which killed 34 people in the US NOT LONG AGO.