Ionizers generate ozone, that is the same smell that you would have near an electric motor or a copy machine. The smell is caused by electric sparks that occur during the ionization process. Essentially high voltage is applied to a grid, air passes over this grid and electrons jump off of it and into the air. They then attach to any particles that are present in the air and make those particles attractive to anything less charged than they are. There is a limit to how much ozone an air ionizer is allowed to produce because ozone is a respiratory irritant and is not desirable to have in large amounts. Ozone also damages rubber. A commercial air purifier has to certify that it is in compliance with that law in order to be sold. The difference is that they can change characteristic based on how clean the grid is and how much humidity is present.
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Ionizers generate ozone, that is the same smell that you would have near an electric motor or a copy machine. The smell is caused by electric sparks that occur during the ionization process. Essentially high voltage is applied to a grid, air passes over this grid and electrons jump off of it and into the air. They then attach to any particles that are present in the air and make those particles attractive to anything less charged than they are.
There is a limit to how much ozone an air ionizer is allowed to produce because ozone is a respiratory irritant and is not desirable to have in large amounts. Ozone also damages rubber. A commercial air purifier has to certify that it is in compliance with that law in order to be sold. The difference is that they can change characteristic based on how clean the grid is and how much humidity is present.