A reader asks:

What is the recommended method of use of a negative air ionizer during the day? When should it be turned on, and for how long?



If used during the day for its antidepressant effect, follow the standard instructions for treatment at a close distance (please see the FAQ).

If used for daytime air purification in a single room, the unit can be operated continuously without confinement to a close distance.

Windows and doors should be shut or nearly shut to allow ion concentration to build up throughout the space.

Rooms with central air conditioning and continuous air replacement will significantly reduce ion availability.

Depending on room use during the day, several ionizers may be needed for air purification of a multi-room home.

The units can be turned on and off flexibly, depending on room use, although it can take up to an hour for ion concentration to build up after the unit is turned on.

For further information, please browse our section on negative air ionization.