Honeywell F58F Owner's Manual - Page 18

Use a carbon filter to remove odors The electronic air cleaner versus the air ionizer Ozone and the electronic air cleaner Odors are gases, not particles. They cannot be removed by the air cleaner or by any other filter designed to remove particles. However, some gases can be trapped by an activated carbon filter or diluted with outdoor air. If odors are a concern, talk to your heating and air conditioning dealer about installing a carbon filter downstream of the air cleaner or providing an outdoor air inlet. Air ionizers have been marketed with claims about purifying the air and promising medical benefits. It should be noted that supporting tests, if available, are controversial and incomplete. Air ionizers may generate a bit of ozone, and of course some ions (air molecules with an electric charge). This is what your electronic air cleaner's ionizer does, but with greater intensity. However, air ionizers do not have good collectors, if any. With air ionizers, the charged dirt particles are collected by walls, floor and furniture, requiring frequent cleaning of the entire building to remove the effects of collected contamination. By comparison, an electronic air cleaner deposits contamination on the cell(s) and prefilter(s) for easy cleaning. Electronic air cleaners generate a very small amount of ozone, about 0.005 to 0.010 parts per million (PPM). The amount is highest when the air cleaner is new. The average person can detect the odor of ozone in concentrations as low as 0.003 to 0.010 PPM. The U.S. Food and Drug Administration, and Health and Welfare Canada recommend that indoor ozone concentration should not exceed 0.050 PPM. As a comparison, the outdoor ozone level in major cities is sometimes higher than 0.100 PPM. 69-0764-2 16