Michigan Sinus Center director demonstrates how to build cheap home air purifier

Jul 2 2011

Many people with sinus problems have underlying allergies to dust, pollen, mold or animal dander. All of these can build up in the air inside homes.

One of the best ways to get rid of allergy symptoms is to avoid allergens in the first place, says Jeffrey E. Terrell, M.D., director of the University of Michigan Health System's Michigan Sinus Center. To avoid indoor allergens, many doctors recommend using an air purifier with a High Efficiency Particulate Air (HEPA) filter.

The cost of these machines can run from $75 up to $800 for high-end systems.

For those who are looking for a cheaper alternative for high-use rooms such as the bedroom, Terrell offers a do-it-yourself solution at a fraction of the cost.

"This is a filtration system that you can put together with items from your local hardware store for $25 to $30 and use in your home to cut indoor allergens by about 90 percent," says Terrell.

Start with a 20-inch by 20-inch box fan, which often retails for about $12. To the front of it, tape a 20-inch by 20-inch by 1-inch furnace filter.

Make sure that filter is a HEPA filter with a Minimum Efficiency Reporting Value (MERV) rating of at least 13. The higher the rating, the more particles will be filtered out of the air. These filters sell for about $15.

There will be arrows marked on the filter to indicate the proper direction for airflow. Attach the filter to the front of the fan, so the air blows through it.

In a videotaped demonstration, which can be viewed at http://bit.ly/lX4ZqI, Terrell used a sensitive air-quality meter to demonstrate that one high-end HEPA system brought the particulate count in a dusty room down to virtually zero. His homemade system brought the count down to about 10 percent of its former level.

The homemade purifier can be placed on the floor. If it's in a window, it will filter pollen blowing in from outside but won't have as much of an impact on the air that's already in home. People who have pollen allergies should keep their windows closed, Terrell notes.

"You can tell when it's time to change the filter by its color," Terrell says. "As dust and particulates get caught in the filter, it will turn from white to brown."

Source: Michigan Sinus Center