Knit Blog

How clean is the air your sleeping child is breathing? Indoor pollution can wreak havoc with sleep by causing breathing problems, triggering allergies and asthma and affecting long-term health. If your child’s breathing is worse at night than during the day, or if she wakes with a stuffy nose and red eyes year round, that’s a likely sign that she’s suffering from indoor allergens. But the signs of possible indoor pollution could be much more subtle: mold growing in corners of the bathroom, an occasional odd smell in the kitchen or even just moisture condensation, which could indicate poor ventilation in your house.

Could better indoor air quality improve your child’s sleep? Although the primary concerns with indoor air pollutants, according to the Environmental Protection Agency, are their impact on the lungs and the heart, there’s evidence that good ventilation in the bedroom can improve sleep as well. And, of course, if your child suffers from allergies, then indoor pollution from allergens will trigger a reaction and exacerbate sleep problems.

There are two main types of indoor air pollutants: particulate and gaseous. Particulate pollution is caused by solid or liquid particles that are small and light enough to stay suspended in the air. If they’re smaller than 10 micrometers in diameter, they can be inhaled into the lungs or even the bloodstream. Inhaled particles can irritate the airway and lungs, causing coughing or shortness of breath, and they can aggravate asthma. Any type of particle can cause problems, but particles of allergens like pollen, mold or pet fur can cause even more issues by triggering allergies as well.

Gas pollutants are usually caused by something burning, such as a gas stove, fireplace or cigarettes, but they can also come from synthetic materials that off-gas, such as paints, cleaning products or pesticides.

If you suspect indoor pollutants, there are three major steps you should take. First, you can reduce indoor pollution as much as possible by changing the environment in your home. This is the best way to get rid of pollutants, especially allergies: avoid them rather than cleaning them. Next, you can improve ventilation in your house, increasing circulation of outside and inside air. If the outdoor air is cleaner than the indoor air, this will improve the quality of the air inside. However, if the outside air is also highly polluted, then the third step - cleaning the indoor air with a filter or cleaner - becomes even more valuable.

First, Reduce

Before introducing an air filter, do everything possible to reduce pollutants in your child's room.

Start with the simple solutions: get rid of unnecessary fabric that can harbor dust mites and mold. Consider swapping fabric curtains out for light-blocking shutters, and get rid of any decorative rugs or pillows in the room. If you do keep curtains, wash them in hot water once a week. Do the same for sheets, pillows and blankets. Keep stuffed animals and other fabric toys stored away from the bed, and wash them at least once a month. Never use candles or incense in your child’s room (use a scent diffuser if you want calming smells in the bedroom), and of course, never allow anyone to smoke in your child’s room. If you have a fireplace in your child’s room, don’t use it. When cleaning or painting in your child’s room, use non-toxic materials that don’t off-gas.

Next, consider more extreme solutions: if your child’s room has a carpet, refinish the floor with a non-fabric option like wood, tile or vinyl. Keep your pet out of your child’s room, and especially off the bed and furniture. If anyone in the house smokes, quit. Get rid of any fabric furniture like cloth couches or chairs, and replace them with leather or vinyl seats that won’t collect dust. Don’t use a fireplace or wood stove, and avoid burning candles anywhere in the house.

Then, Cycle

The next step is a very simple one: improve ventilation. In many cases, the quality of outside air may be better than your indoor air, especially if your house contains allergens like mold and dust mites. If that’s the case, then simply cycling the air better, allowing airflow from the outside, can improve the indoor air quality and improve your child’s sleep. In warm weather, try opening a window or a door, and if you have a window air conditioning unit or attic fan, turn those on. Most whole-house HVAC systems do not cycle air from the outside, so be aware that turning on the air conditioning won’t change the concentration of indoor pollutants - it only recycles the same indoor air.

When cycling outside air, however, be careful not to increase allergens inside the house. If your child’s allergies are seasonal and triggered by outdoor pollutants like pollen, then opening doors and windows will increase the allergens inside your house.

Finally, Filter

If the air quality in your child's bedroom needs further improvement, it’s time to consider an air filter. There are several types of air cleaners, and depending on what type of pollutants you have in your house, you may need more than one type.  

Mechanical filters help with particulate matter that’s suspended in the air. They remove pollution particles by running air through a mesh or screen made of fibers that trap the particles. This is the most common type of filters, and it’s the most effective for most types of allergens, including dust mites, mold, pollen and smoke particles. The efficiency of a mechanical filter is measured by its Minimum Efficiency Reporting Value, or MERV.

The standard for air purification by a mechanical filter is HEPA, or high-efficiency particulate air filter. Its MERV rating is 14-16, which means it removes 97% of particles from the air. Unlike other mechanical filters, like fiberglass filters, you can’t just add a HEPA filter to your existing fan system, because the fine mesh means you need a fan with strong air pressure to push the air through the filter. Adding a HEPA filter for your whole house means installing an entirely separate system in addition to your existing A/C system. However, you can also get single-room HEPA filters that are enclosed systems.

Electronic filters are another way to filter particulate pollutants out of the air. Instead of pushing air through a mesh, electronic air cleaners use ionization to attach ions with an electric charge to particles and then to collect them onto a collection plate with the opposite charge. There’s no standard for measuring electronic air cleaners, and although they can be effective for small particles, they may not work as well for large particles. In addition, they often produce ozone, which can irritate your child’s lungs.  

If your main air quality problem is gases, not particles, then you’ll need a gas-phase filter. The most common type of gas pollutant is Volatile Organic Compounds, or VOCs. These are gases that are emitted from many common household materials, such as paints, carpets, adhesives and upholstery. Gas-phase filters use activated carbon to adsorb gas particles. The activated carbon captures gas molecules, removing them from the air. However, gas-phase filters are designed to capture a particular type of gas, so you’ll need to test your air to determine what type of gas has high levels in your home.

For any type of filter, you can choose between a whole house filter or a portable single room filter. A whole house filter usually needs a separate HVAC system, and you’ll need it installed by a professional. However, a single room filter, in addition to being less expensive, can actually be more effective in that room, even though it won’t affect the rest of the house. If your main concern with air quality is your child’s sleep, then a single room filter in your child’s bedroom could be the best choice.

How to decide

If you’re considering getting an air filter, the first question to ask is what pollutants are having the biggest impact on your child’s health and sleep. If you know your child has allergies to things that you can’t keep out of the house, like the dander from a pet, then a HEPA filter in your child’s room could make a big difference. But if the main problem in your house is VOCs, then a particle filter won’t have any impact. No type of air cleaner filters everything at once, so you need to identify the main problem before you invest in an air cleaner.

Second, consider the filter’s efficiency. This includes both how much of the pollutant it removes and how quickly it works. A filter that is too slow won’t provide enough clean air, so make sure you choose the right efficiency for the size of the space you want to clean.

Finally, consider the filter’s ease of use. How expensive is it? Does it need to be cleaned frequently, and how difficult is it to clean? Is it noisy or irritating? These should factor into your decision as well.

No air filter is 100% effective, and prevention is the best way to improve the air quality in your child’s bedroom. However, if your child is sensitive and you’ve done everything else you can to reduce pollutants, the right air cleaner can make a big difference to a good night’s sleep.