Look for these key characteristics when shopping for a room air cleaner.


Many room air cleaners can be moved around the house and used in different rooms, as long as the rooms are similar sizes.


Some room air cleaners provide more filtering power than whole home units.


Different air cleaner manufacturers offer various features, styles and filtering technologies to meet an array of consumer needs.

Air Cleaner Filtering Technologies

Air filters feature different technologies to suit your lifestyle and home.

HEPA filters

High Efficiency Particulate Air (HEPA) filters are designed to remove 99.97 percent of all airborne pollutants 0.3 microns or larger from the air that pass through the filter, including tobacco smoke, household dust and pollen. For reference, a micron is 1 millionth of a meter and a human hair may be between 17 and 180 microns in width. Read AHAM’s white paper, “HEPA Filtration – Discussion on Test Methods and Ratings,” for an in-depth explanation of HEPA.

ULPA filters

Ultra-HEPA filters are designed to trap 99.999 percent of all airborne particles 0.3 microns or smaller that pass through the filter, including tobacco smoke, household dust and pollen.

Electrostatic filters

Electrostatic units filter the air using static electricity. Many particles normally carry a slight static charge. The filters have a static charge to allow airborne particles to “stick” to it, just like static-charged clothing sticks together.

Electrostatic precipitators

These air cleaners create opposite charges on the metal plates or wires in a “filter” assembly. They attract the dust, pollen, smoke and other particles to the plate or grid wire that contains an opposite charge. Then they can be washed and reused.


Ionizers may be combined with other technologies, including different types of filters. Ionization units emit a small charge to the airstream which cause particles to adhere to the filter or other surfaces by a magnetic-like attraction.