If you have symptoms of asthma, an air filter may help you breathe better. Same is the case for those who suffer from hay fever (allergic rhinosinusitis) or COPD (emphysema or chronic bronchitis). If your roommate is a smoker, an air filter will be helpful to you. Secondhand smoke worsens the symptoms of asthma. It also causes nasal congestion in children.
Asthma and Room Air Cleaners
Can air filters help prevent symptoms for asthma? Possibly yes. Room air cleaners remove small particles from the air near the cleaner. However, they don’t remove small allergen particles that are mostly caused by local disturbances. You end up inhaling these allergens before they get near the room air cleaner. Room air cleaners usually take about 5 to 15 minutes to eliminate temporary local sources of dust and allergens.
Wall-to-wall carpet is a huge source of allergens. These allergens cannot be removed by vacuuming or a room air cleaner. But the allergens remain intact in the carpet until they are disturbed. Following are the types of air filters available.
Mechanical Air Filters: It uses a fan to force the air through a specialized screen. This screen traps particles of smoke, pollen, and various other airborne allergens. The High-Efficiency Particulate Air (HEPA) filter is one of the best air filters available. HEPA (a type of filter, and the name of a brand) was developed during World War II to help prevent radioactive particles from escaping laboratories. A true HEPA filter is able to capture almost 90% of all particles which are 0.3 microns or larger in diameter that enters it. The disadvantage is that the fan makes a lot of noise and it uses a lot of electricity to run the fan motor.
Electronic Air Filters: It uses electrical charges (positive or negative) to attract and deposit allergens. If the particular device has a collecting plate, the particles are stored within the system. Otherwise, they stick to room surfaces and have to be cleaned later. One of the disadvantages of these units is that most of them create small amounts of ozone which irritates the airways, and causes temporary bronchospasm in people with asthma. They also cause nasal congestion in people suffering with hay fever or rhinitis.
Hybrid Air Filters: They have elements from both mechanical and electrostatic filters.