Clearing the Air: How an Air Quality Researcher Takes Care of the Air Her Family Breathes

I’m an indoor air quality researcher and the mom of kids with allergies, so I spend a lot of time thinking about the air we breathe and what’s in it. I take some simple steps at home to ensure that my home’s air is as clean as I can reasonably make it.

In this blog post, I’ll describe some of my practices and explain how the science we do here at NIST supports cleaner indoor air for everyone.

Air Cleaning: Kitchen

When I cook, I always use my ventilation fan above the stove. It sends the particles from cooking outside the house.

But not everything will escape outside, so I also run an additional, stand-alone air cleaner in my kitchen. Home air cleaners remove particles like dust, pollen, viruses and smoke. The air cleaner I use has a color-coded light that indicates the level of particles it’s measuring in the air. The indicator light lets me know if I need to keep the fan running longer or if the air is back to baseline (which I hope is relatively clear).

These color-coded readings are for in-home use. So, I’m not expecting laboratory-grade measurements, but they do increase my awareness of what’s in the air. I watch the indicator light and like to know that I’ve done everything I can to keep our air as clean as possible.

While my air cleaner is great at removing particles, it can’t measure or remove gaseous chemicals, like volatile organic compounds (VOCs). VOCs are found in almost every household product, and they can be reduced by finding replacements, limiting their use or removing them through ventilation. For example, water, vinegar and baking soda are awesome cleaning agents!

Air Cleaning: Bathroom and Bedrooms

In both my and the kids’ bathrooms, we installed timers for the exhaust fans so they can run for 15, 30, 45 or 60 minutes. After showering, we shut the bathroom door and leave the fan on the timer to remove all that moisture, which can limit the risk of mildew and mold growth. The exhaust fan can also remove any particles and chemicals after using cleaning or personal care products.

My kids and I all have allergies, so I keep air cleaners in the bedrooms. One of the most important things about having an air cleaner in your home is changing the filter regularly, just like you do for your home’s HVAC system. Dirty air filters reduce the air flow through the system. Lower flow means less air gets cleaned. I have a task reminder on my phone to change those filters regularly to help all of us manage our symptoms.

Air Cleaning: Travel

I even have a portable air cleaner that I use for traveling to hotels or vacation rentals. You may not think about the air quality in these spaces, but it’s something you can’t control the way you can in your home. For instance, if you have pet-related allergies, there may be remnants from a previous visitor’s pet in the air.

My son has the worst allergies in the family, so I put a portable air cleaner in whatever room he’s staying in. An unexpected benefit of this is that these machines also act like white noise to help kids sleep when away from home!

Thinking About Cleaner Air at Home

We have a wonderful dog, so my home is certainly not free of allergens. However, these steps, along with regular cleaning and changing filters, have helped us manage our family's allergy symptoms.

I choose air cleaners that only remove particles from the air, not technologies that may add things to the air, such as UV light, ions or strong electronic fields. Researchers don’t know enough about additives that these technologies generate to know if and when they are safe for everyone.

If you’re considering buying an air cleaner for your home or your travels, the most important parameter is having a high enough airflow. Just as an air cleaner won’t work if you forget to turn it on or it’s not right for your space, an air cleaner with a flow you can’t feel won’t have much of an impact on the room either.

To ensure proper performance of the air cleaner, look for certifications from the Association of Home Appliance Manufacturers. Products with this certification will list a clean air delivery rate (higher is better) and the square footage that it is designed for (with standard ceiling height).

For effective air cleaning, the listed square footage is the square footage between closed doors. So, air cleaning machines are also most effective in enclosed spaces, like a bedroom or bathroom. If you have a large, open-concept room, you’ll need to plan for more machines or just understand that a single cleaner may not work as well as it would in a smaller, enclosed room.

Another factor to consider is that products are often rated for a certain speed. To get the rated performance, you’d need to run your air cleaner at the same speed. Sometimes, that might be a speed that’s too loud for you. In this case, you may want to run two or more air cleaners at lower speeds. Or I might let the air cleaner run for a bit at a higher speed and then come back later and turn it down. That at least ensures that for part of the day, the machine is running at the highest speed and removing as many particles from the air as possible.

If you’d rather not buy an air cleaner, you can build one relatively inexpensively. During the COVID-19 pandemic, two air quality experts worked to create an inexpensive air cleaner, known as a Corsi-Rosenthal Box. Researchers found that these boxes were as effective as commercial products at removing particles (and viruses that stick to them) from the air.

Indoor Air Quality Research and Standards

I lead the division that includes NIST’s indoor air quality research efforts. Our work is important because we all spend so much time indoors, from homes to schools to office buildings.

Our team recently studied wildfire smoke in one of our Gaithersburg campus’s research houses. We looked at how smoke spread through the house. We also sealed off one room and ran a single air cleaner, demonstrating that it can create a “clean air space.” People could potentially use this approach during wildfire events if they’re close enough to have excess smoke but not near enough to need to evacuate. 

Our research team is still working to gather and publish that data, but I hope our research can inform how people protect themselves during increasingly common wildfire events.

Additionally, our team is leading the development of standards that measure chemicals removed (or generated) by air cleaners to ensure a level playing field in this market. For example, when an air cleaner makes a claim like “removes formaldehyde,” there needs to be a way to verify how much it’s removing. In addition, the standard aims to measure the air cleaners’ unintended byproducts, such as ultrafine particles, that potentially can impact health.

NIST does not create these standards, but we share our research with standards-creating organizations, such as ASTM and ASHRAE, to help inform their decisions. These organizations use a consensus-making process, meaning that everyone has a seat at the table to create a standard that addresses concerns.

Inspiring the Next Generation of Researchers

One of the things I love the most about my job is explaining science to students and helping them consider pursuing a career in it.

I usually start my speech to young children by encouraging them to take a deep breath. Then, I ask them to smell what’s in the air. I ask, how do we reduce the things in the air that we may not like smelling, such as chemicals? I’ll talk about the HVAC system in their school. If there’s an air cleaner in the classroom, I’ll explain what that does. It helps kids understand what indoor air quality research is at a level that’s familiar to them.

I spend a lot of my time doing mentorship and outreach, especially to younger students. Sadly, one of the statistics we’ve learned is that students, particularly girls, often lose interest in science by middle school. So I hope to encourage that interest at a young age, so those students stay engaged throughout their education.

I try to make the indoor air quality field seem as relatable as possible because it’s of interest to everyone. What we do is highly technical, but it’s far from boring. It has a real-world impact on people’s lives.

I always tell the students I talk to: If you have problem-solving and teamwork skills, you can help solve some big, real-world problems in a science career. There is no shortage of problems for scientists and engineers to work on, and I look forward to seeing what future generations of researchers bring to NIST and our field.