By Andy Pace
Just about every day in the last 32 years, I’ve taken phone calls from customers all over the world complaining about a single issue. “My house is off-gassing and I’m getting sick from the odors.” I thought it would be a good idea to share this discussion with Healthy Home Media readers and discuss what people are actually dealing with and identify realistic solutions. For readers to relate to one common example, I will defer to paints, however hundreds of other materials could be contributing to toxic off-gassing in our homes.
What is Off-Gassing:
Let’s first understand exactly what off-gassing is. In the most basic terms, off-gassing is the release of unreacted chemical monomers from a solid material, like a painted wall. These chemical monomers have not become part of the solid material and never will be, thus, they release slowly over an unknown period of time. Do not confuse this with the curing of the paint. The curing process is the coalescing of the film as it dries. Let's take, for instance, a water-based paint that is essentially a liquid plastic, acrylic, and it's held in suspension with water. As the water and the solvents start to evaporate off of that liquid surface, it creates a film. That's the coalescing of the film and ultimately the boring process of watching paint dry or cure. As paint turns from a liquid to a solid, it shrinks a little bit ever so slightly and it grabs onto the surface. Now, most of the curing process is done in the first 24 hours. The last 5% of drying on average can take up to two weeks to evaporate. Once the paint is fully cured and there's no more water, there's no more solvent coming off the surface, and there's no more shrinking of that film to stick. This is when off-gassing begins. I want to make that differentiation because a lot of people confuse the terms off-gassing and curing.
Back in the 1990s, the EPA’s National Risk Management Research Laboratory (NRMRL) began to investigate how architectural paints and coatings could contribute to indoor air pollution and harm human health.
A few key points they gave include:
1. The majority of emissions from latex paint occur after the coating has dried.
2. It may take as long as 3.5 years for some VOCs to be released from the gypsum board.
3. Some paints marketed as “Low or ZERO-VOC” may still emit significant quantities of Hazardous Air Pollutants.
ZERO VOC:
So what exactly is coming off of the cured paint? Government regulations have increasingly restricted the presence of chemicals in paints and coatings that might have a negative impact on the atmosphere (regarding smog creation), but strict regulations for chemicals that might have an impact on human health have yet to be implemented. I would like to stress the fact that coatings that carry a “low” or “zero VOC” label are not necessarily free from Hazardous Air Pollutants (HAPs) or toxins. This is a critical point that is often misunderstood. “Zero VOC” does not mean non-toxic. Some products that are labeled as "no VOC" or "low VOC" contain volatile organic chemicals that are toxic, sometimes at high levels. Chemicals such as formaldehyde coming from fungicides, flame retardants, and pesticides in addition to isocyanates coming from two-part epoxies or urethanes are toxic. Besides paints and varnishes, they're also in caulk, air fresheners, cleaning products, smoking, carpet, vinyl and composite flooring, dry cleaning, photocopiers, petroleum products, natural gas, upholstery, foam, and wood-burning, according to the EPA.
Off-gassing is not like steam coming off a bowl of hot water. If you take a bowl of hot water and it's steaming and you want to block that steam, you put a piece of plastic over it. Well, what happens? It builds up pressure underneath that plastic. You poke a hole in it and all the steam in that bowl will come out of that one little hole. Off-gassing is not like that. Formaldehyde coming off of a surface does not migrate to that one pinhole to come out of that spot. It releases a chemical vapor off the entire surface like dust covering a large area.
Mitigate Off-Gassing:
Now that we all know what off-gassing is….how do we get rid of it? There are three good options, none of which are perfect. The best and most effective way is to get rid of the offending material. For instance, If you know the kitchen cabinetry is the cause of an extreme amount of chemical off-gassing, then replacing it with a known safer material will fix the situation. This option is often at a tremendous expense.
The second best way is to allow time and airflow to heal the wound. Most chemical off-gassing from a cured surface will last 2-4 years tops. However, off-gassing from particle board, plywood, carpeting, etc can last 20-40 YEARS. In those cases, time alone is not going to help. Using fans to circulate fresh air into the home and blowing stale air out can offer great improvements to indoor air quality, especially when dealing with new building materials. The third best way to prevent the chemical release is to use a sealer. Depending on the offending material, like cabinetry and carpeting, often too expensive to replace, a sealer like AFM Safecoat paint products and carpet cleaner is a great and cost-effective solution.
What NOT TO DO:
Do not, in any circumstance, use the method of baking out to attempt to lessen the off-gassing of your home. Baking out refers to increasing the building temperature up to 100°F in order to speed up the aging process of the building materials. Research shows that levels of VOCs after a bake-out are sometimes much greater than before the bake-out. VOCs can be released and re-absorbed by walls and furnishings in the building. Likewise, it is possible that warping or damage of interior finishes and/or the HVAC system will occur at these heightened temperatures. The small chance of improvement is not worth the chance of voiding material warrantees and potentially causing permanent damage to your home.
To summarize, off-gassing and curing are two completely different things. One cannot “off-gas” something by force. It occurs naturally, on its own timeframe. All we can do is eliminate it by making better choices, sealing, or having patience.
By, Andy Pace
Healthy Home Concierge,
Founder of the Green Design Center and Host of the Non-Toxic Environments Podcast
About Andrew Pace Andrew Pace is a Healthy Home Concierge and Founder of The Green Design Center, a leading resource for homeowners and contractors looking to source products that are healthy and green and receive expert consulting advice on designing and building healthy green homes. Andrew is the host of the weekly Non-Toxic Environments Podcast. He is a worldwide expert on green and healthy building products and services for customers and contractors from around the globe. As founder of the oldest healthy building supply company in the United States, Andrew has become one of the single most helpful and educational experts dealing with the day-to-day concerns of those individuals who suffer from allergies, asthma, and chemical sensitivities. Please follow along at @nontoxicenvironments and https://www.thegreendesigncenter.com.
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