Twin Air Pro 2 Ionizer from NaturAir
The NaturAir Twin Pro 2 Ionizer

This unit is manufactured as an air purifier by NaturAir, Inc. Its therapeutic use is based on research at Columbia University Medical Center. The supporting clinical trials, sponsored by the National Institute of Mental Health, found that daily exposure to negative air ions at the high flow rate produced by such a powerful device could reduce symptoms of depression.


  • A harmless static buildup may be noticed when a grounded surface is touched immediately after being close to the unit. The static electricity is normal and safe, but don’t allow children or pets to touch or get close to the device.
  • Remove any electronic equipment near where you sit during treatment sessions. Negative air ions will flow toward any electrically grounded device, such as a computer, telephone clock radio, or TV. If these objects are placed at the far side of the room, you become the best-grounded object of ion flow, which maximizes the ion dose of your treatment. Your sitting position should be closer to the ionizer than any electrical devices, to ensure the ions flow in your direction. 


  • Place the unit on a table or small stand – even a sturdy cardboard box – preferably at least 2 ft(60 cm) from a wall and 2-3 ft off the floor. Walls tend to be positively charged, and the negatively charged particulates will be attracted to the walls at a higher than normal rate. Or choose a wall with a smooth, easily washable surface.
  • Orient the unit facing you, with the NaturAir imprint showing. To maximize the benefit, your distance should be about 3 ft (90 cm) from the two emitter towers.


ionizerDaily post-awakening treatment sessions. This is the method originally established for treatment of winter depression (Seasonal Affective Disorder). Patients awoke at a consistent hour each morning, leaving time for the treatment session and preparation to leave the house for work. Within minutes of rising, and grabbing some breakfast from the kitchen, they sat by the ionizer at 2 to 3 feet (or about 60-90 cm) for 30 minutes, carefully timed. After the session, they prepared to leave the house (showering, dressing, etc.). They followed the same schedule on weekends, resisting any temptation to sleep in. While this schedule proved effective, changes from it may also work, with sessions later in the day, for example. Each new user should test any desired variations in scheduling (for about a week at a time), and compare the outcome with the original research schedule.

Use in the bedroom during sleep. Later clinical trials tested the antidepressant effect of negative ion exposure in the bedroom during sleep. This method provides the convenience of automatic action without reserving a daytime interval for treatment. For this application, place the ionizer on a night table, with the two ion emission towers facing the pillow area at the top of the bed, again at 2-3 ft from the head. Plug the unit into a 24-hour electronic appliance timer set to switch on power 90 minutes before wake-up time, with automatic switching off around the time you get out of bed. Make sure the timer you select operates silently, so there is no distracting sound of clicking when power switches on: you should take care not to be awakened by the sound of a click! One such low-cost timer is available from Amazon*.

A second option, all-night exposure to negative air ions, may produce the strongest results for some people, though it has not yet been tested systematically in clinical trials. For example, a bedroom – a 20 x 20 ft (6 x 6 m) room with doors and windows shut — will reach negative ion “stasis”, or saturation, in about an hour’s time. Again, the unit should be placed away from other electrical appliances that will tend to attract the ion flow, reducing the therapeutic effect. The unit can be operated 24/7; or turned on at bedtime, and turned off upon rising; or scheduled for automatic electronic switching. In any case, do not place the ionizer against the wall, as this will increase the buildup of particles. It can be placed farther from the bed than for 90-minute sessions, since the whole room will reach a high level of ion density.  Ion density is maximized if the room is humidified, especially when air-conditioned in summer, or heated in winter.

Progressive ion dosing: the smartest strategy when starting daily sessions. When negative air ionization is used to improve mood and energy, it is useful to take a lesson from psychopharmacology, even though drugs are not involved here. One begins at low dose, evaluates effectiveness after a test period (for ions, say, one week), and then increases dose incrementally, if needed, to seek a successful response. One should not exceed the optimum dose, which might result in negative side effects and reduced effectiveness. Of the treatment options described above, the order of dosing from lowest to highest would be:

     i. 30 minutes after waking. This schedule has been the most investigated in research trials, and has shown a success rate similar to bright light therapy. No side effects have been reported to us. If necessary, the duration can be increased from 30 to 45 or 60 minutes, but in many cases that does not appear to add advantage. If the post-waking timing succeeds but the early timing is inconvenient, the sessions can be delayed to later in the day, or even taken at variable times of day. However, we advise first testing morning sessions to allow a comparison.

      ii. 90 minutes before wake-up time, using a 24-hour on/off appliance timer. The total dose is higher with this schedule but has produced results similar to the 30-minute post-waking schedule, also without reports of negative side effects. Some people who have not responded to morning sessions may still respond to negative air ion therapy during the last period of sleep before morning wake-up.

   iii. All-night sessions. This is the highest dosing schedule and should be used only if the first two schedules yield incomplete improvement, and there is reason to believe longer exposure might succeed. The bedroom door should be left open a few inches or a window cracked open to allow some exchange with non-ionized air. If the room is tightly closed, ion concentration can build up beyond therapeutic levels, with a slight chance of one experiencing excess energy, a “speedy” sensation, or agitation that can linger throughout the day. These side effects have been reported only in a handful of cases out of hundreds, and usually resolve within day, but they are important to note nonetheless.

     iv. Light therapy plus ion therapy. While any single treatment for mood and energy may provide partial benefit, add-on treatments can boost the benefit. Many people have inquired about combining ion therapy with light therapy. We caution against using both methods at the same time, since the light therapy device, with a grounded power line, will preferentially attract the negative air ions, greatly reducing the ion dose received. Alternatively, the 90-minute ionizer schedule at the end of sleep can be combined with a standard 30-minute schedule of light therapy after waking up, or the 30-minute ion sessions can be taken at a different time of day. Commercial devices that integrate the two treatment methods should be avoided.

For more information about the Twin Air Pro 2, and its unique design and power specifications, visit NaturAir Ionizer.


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