Air Filtration Systems
The actions described previously are first-line measures to control allergy exposure. Once the first-line actions are taken, air filtration systems (HEPA filter) can aid some children by decreasing exposure to allergens and reduce asthma symptoms. The air filtration system must be carefully selected and properly maintained. Purchase such equipment only if your doctor advises that the benefits will be worth the expense.
Central or room air conditioning may reduce the number of airborne allergens by making it easier to keep windows and doors closed in hot weather. This may be helpful for children with pollen and outdoor mold allergies. Central air conditioning also has the benefit of lowering the humidity within the home. This is helpful in controlling mold and house dust mites.
Humidifiers, Vaporizers and Evaporative (Swamp) Coolers
The use of humidifiers, vaporizers and evaporative coolers is not recommended in the homes of children with asthma. All three increase the humidity level in the home, creating an ideal environment for house dust mites and mold growth. If you must use any of these devices, clean them regularly.