Spring is a great release for us humans after a long, hard winter. The bad news is it’s also a great release for allergens. The combination of warmer temperatures and increasing humidity that causes trees and plants to unfurl leaves, flowers and catkins and all their pollen also lead to increase growth in two other major allergens: dust mites and mold.
While pollen affects indoor air quality an outside allergen source, and dust mite populations are typically generated inside the house, mold sources can be both inside and outside.
If you’ve got allergies, you’re all too familiar with the symptoms, but here’s a recap anyway:
- Runny or stuffy nose
- Red, itchy or teary eyes
- Wheezing, coughing, tightness in the chest and shortness of breath
Spring’s Big Allergen Trio
Those lovely warm, windy days are usually when pollen counts are highest. Mowing the lawn or raking up leaves stirs up huge amounts of pollen. Pollen counts are lowest just after rain, when the dust is all stuck to wet surfaces.
Mold growth can happen throughout the year, but ‘blooms’ of spores occur when temperatures don’t go below 70°F and relative humidity stays around 70%. These are ideal conditions for huge increases mold growth. When mold blooms outside, clouds of spores are in greatest concentrations within 3 feet of the ground. While the wind will disperse some, most of the spores will drop to the ground, where they will get picked up by foot traffic.
When mold blooms inside, you’re more likely to encounter a growing patch of black or sooty material on a surface than a cloud of spores. Cleaning these up with a bleach solution (1 part bleach to 3 parts, clean but don’t rinse) will slow or even stop the current bloom but won’t stop the source of humidity.
Dust mites, tiny creatures you can’t see with the naked eye, love warm, humid places. Your house doesn’t need to be visibly dirty, they live in pillows, mattresses, upholstered furniture, and carpeting. The process of cleaning can stir up dust particles, making the particles, and the mites, easier to inhale. Dust mite population explosions happen temperatures around 70°F with relative humidity at 75-80% percent. The mites die when the humidity is below 50 percent.
Avoid Triggers, Reduce Reactions
Avoiding allergic reactions is partly a matter of knowing what allergens trigger reactions for you, and when or where you’re likely to be exposed to those allergens, and how you can avoid them. There are other ways to reduce or eliminate your exposure, but avoiding allergens is a good start.
Some ways to make your house less inviting to allergens, listed from easiest to hardest/cheapest to most expensive or disruptive):
- Shoes off at the door to minimize the amount of pollen and mold brought into the house
- Don’t make your bed (fold the blankets, comforter and duvet down so that the heat and moisture you generate in bed has a way to disburse)
- Use “mite-proof” cases on mattresses and pillows and wash bedding frequently in hot water
- Keep your windows closed on warm, windy days
- Wash your hair in the evening to avoid bringing pollen into your bed
- Use high-efficiency media filters in your HRV, furnace and air conditioning unit
- Minimize household humidity
- Remove wall-to-wall carpets, particularly in the bedroom, replace with laminate, engineered flooring or hardwood
- Keep pets out of the bedroom, and preferably out of the house (this is a tough one, so it’s a last resort!)
Order Up Fresh Air, Hold the Allergens
To reduce moisture levels inside your home and reduce the dust mite population and mold growth, you can turn to air conditioners, dehumidifiers, and HRV systems. An HRV can help maintain a healthy relative humidity level throughout your house, preventing spring allergen problems. However, existing mold problems caused by water leakage will not be stopped by ventilation -- the problem needs to be addressed at the source.
Zehnder HRVs offer fresh, filtered air delivery throughout your home. Filters are rated by a Minimum Effiicency Reporting Value (MERV) Rating. The higher the MERV rating, the fewer dust particles and other contaminants can pass through it. On Zehnder HRVs, a standard filter (MERV 7 to 8) removes pet dander, pollen, dust mites and droppings, auto emission particles, and lead dust. The optional finer filter (MERV 13) removes even smaller particles. The filters are easy to remove from the unit to either vacuum or replace.