You can improve the quality of the air in your home by using a humidifier or air purifier. If you have allergies or are bothered by dry air, you can set up one or both of these in your bedroom where you spend most of your time. While each of these can improve air quality, they work in different ways.
Humidity
A humidifier adds humidity to your home or to a single room, but it does not remove contaminants from the air. This helps during dry winter months when humidity levels are low. Increasing the humidity in your home may help combat dry skin and ease a dry cough. Humidifiers put either cold or warm humidity into the air. According to Go Ask Alice at Columbia University, they may help relieve symptoms of a cold but they don't cure colds or sore throats.
Contaminants
Air purifiers work to remove dust, mold, dander, smoke and other contaminants from the air, according to the Ready America website. They do this with a HEPA filter. Air purifiers with HEPA filters can be small personal units attached to a mask or larger units for the whole house. These devices benefit people with asthma and allergies as they continually circulate and filter particles out of the air.
Price
Humidifiers can be inexpensive, especially the smaller bedside units. Since air purifiers are more complex machines, they are generally more expensive. Air purifiers can cost hundreds of dollars.
Maintenance
Humidifiers must be cleaned according to manufacturer's directions in order to prevent the growth of bacteria and mold. This may require emptying and refilling the humidifier on a daily basis. The Environmental Protection Agency recommends that you use distilled water in a humidifier to prevent build-up of mineral scales that can promote bacterial growth. The collection plates and filters in air purifiers must be cleaned or replaced according to the manufacturer's recommendations in order to keep the unit functioning properly.
Considerations
Care must be taken not to run a room humidifier so that the humidity level exceeds 50 percent. The Environmental Protection Agency recommends you buy a hygrometer at a hardware store if the humidifier does not display the humidity level in the room. When humidity is too high, bacteria and mold can grow on the walls or other items in the room. Air purifiers that have ion generators work by dispersing ions into the air that cause contaminants to fall out of the air and attach to surfaces like the carpet, wall or curtains. This could cause soiling of these surfaces, and attempts at cleaning may cause the particles return to the air.
