Hello everyone. In this video,
I would like to give you an overview of
the eight major indoor air contaminants that you are going to learn in this course.
Radon is commonly found in soil and building construction materials,
especially those materials made of granite.
Radon is something that you cannot see, smell or taste.
While Radon is indeed dangerous because Radon is a radioactive element.
Indoor aerosol is a suspension of particles in air.
A common category of indoor aerosol is particulate matters, PM.
As you can see,
PM is even smaller than the diameter of a hair.
PM can bring us negative health effects, such as development of
chronic lung disease and increasing severity of asthma attacks in children.
Volatile organic compounds, VOCs,
are a kind of gas that are extremely diverse.
Indeed, many things at home contain VOCs,
for example, cleaning products,
furniture, pesticides, adhesives etc.
In the course, we will introduce 2 common VOCs, Formaldehyde,
which is commonly found in furniture, Tetrachloroethylene,
which is commonly used in laundry.
Another kind of VOCs,
semi-VOCs, has a lower volatility.
Phthalate is an example of semi-VOC which is used widely as plasticizers.
You can find Phthalate in cosmetics,
plastic toys, and food packaging.
Ozone is an indoor contaminant that is released from printers and photocopiers.
Since Ozone is a strong oxidizing agent,
it can react with the organic materials that make
up our body and cause damages in our lungs once inhaled.
Ozone also has negative impacts on metals,
plastic materials and plants.
On the other hand, due to the oxidizing ability of Ozone,
Ozone has potential to remove other air contaminants.
But, there are still some safety issues needed to be considered.
Combustion is a chemical process where a substance reacts with oxygen to produce heat.
Since indoor air contaminants are released during incomplete combustion, in this course,
we will introduce 2 harmful indoor air contaminants
released from incomplete combustions,
Carbon monoxide and Nitrogen dioxide.
Bioaerosols are airborne particles,
large molecules or volatile compounds that contain some biological materials.
3 types of bioaerosols, bacteria,
fungi and viruses contribute to sick building symptom and building related disease.
Asbestos were widely used for building construction several decades ago.
When asbestos-containing materials are damaged,
asbestos fibers are released.
When we inhale those tiny asbestos fibers,
they remain in our body and are not removable.
And, eventually, asbestos fibers cause negative health effects to us,
such as lung cancer.
Edwin and I are going to share with you the properties, measurement methods,
health effects, mitigation and control measures of these indoor air contaminants.
See you in the later videos.