VOCs are volatile organic compounds. This simply means they are chemicals that will evaporate into the air at room temperature. Depending on the concentration, their presence may be noticeable, as when you smell gasoline, or they may be scentless or at a low enough concentration to escape notice. According to the Environmental Protection Agency (EPA), In the factory, several commercial, custom air cleaner solutions exist. Manufacturers are required to remove toxic substances with a fume extractor or air extractor to prevent or minimize release into the environment. This doesn’t help with volatile chemicals that may be trapped in the product when it is sold to the public.
What is outgassing?
The classic example of outgassing is what we call the “new car smell.” Although clever auto manufacturers now use scents to mimic this smell, originally what we were detecting was the evaporation of chemicals from the vinyl and plastic in the newly made automobile. Over time, these substances work their way out of the materials and eventually, the new car smell goes away.
The same phenomenon happens with a wide range of products we purchase, and the smell isn’t always friendly, or even detectable. For example, if you open a sealed bottle of medicine (aspirin or other tablet) and give it a whiff, you will likely detect the solvent used to make the tablet. It doesn’t smell very good at all. Another example is with new carpeting or a garment made from synthetics. A whiff will tell you there are still chemicals outgassing from the item.
As the level of chemical vapors falls, we can no longer detect them easily by smell. However, items may outgas for months or years. This is especially so for items which don’t have good air circulation around them, items made of foams or items exposed to sunlight. This is why carpeting often smells bad to us, especially when we go into someone else’s house or an office building with carpeting – the people who stay there don’t notice, they’ve become acclimated to the smell, but it’s still there.
How VOCs are dealt with
Manufacturers are aware of the problem. Many will hold products until they have released their chemicals below a level consumers can detect them. Others will mask the smell with perfumes or other scents. Industrial fume extractors circulate cleaned air around products in storage to accelerate the process and some even put items under a vacuum with an air extractor to speed up outgassing. But the process isn’t perfect and the levels of fumes are only taken down below where they smell bad, not to zero.
In the home, industrial fumes can also come from items we use in the household. Any product that advises it not be used in an enclosed area is generating these fumes. But we still use them. Even the propellants in air fresheners, hair sprays and other pressurized products release fumes into the air we breathe.
You don’t need a custom air cleaner to remove these substances from the home. What is needed is an activated carbon, or charcoal air filter. By trapping these fumes in a carbon matrix, they can be effectively removed from household air. A mechanical filter, even a highly rated HEPA style, will not trap the fumes, the molecules are simply too small. An activated carbon filter, however, presents an incredibly huge surface area (as much as a couple of miles) and the chemicals are absorbed onto this surface.
This is why a charcoal air filter is combined with a particulate filter in a well designed air purification system. Even when levels have fallen below a level we can smell, the carbon filter is still continuing to trap and remove fumes.