Air ioniser

Ionic air purifiersNegative Ion Treatment for Seasonal Affective
Air ionizers are used in air purifiers. AirborneDisorder
particles are attracted to the electrode in anPublished research shows that high levels of
effect similar to static electricity. These ions arenegative ions are a useful treatment for Seasonal
de-ionized by seeking earthed conductors, such asaffective disorder if the negative ions are in
walls and ceilings. To increase the efficiency of thissufficient density (quantity). Note that this is a
process, some commercial products provide suchseparate issue from air cleaning claims or ozone
surfaces within the device. The frequency ofgeneration that happens in some devices that also
nosocomial infections in British hospitals promptedgenerate negative ions.
the National Health Service (NHS) to research theOne of the pioneers in this area is Michael
effectiveness of anions for air purification. RecentTerman, Ph.D., Director of the Center for Light
SARS outbreaks have fueled the desire forTreatment and Biological Rhythms at Columbia
personal ionizers in the Far East, including JapanUniversity Medical Center and director of the
(where many products have been specialized toClinical Chronobiology Program at New York State
contain negative ion generators, includingPsychiatric Institute. As described in Psychiatry
toothbrushes, refrigerators, air conditioners, airOnline, Terman and several coworkers obtained
cleaners and washing machines). There are nopreliminary evidence that a simulated dawn could
specific standards for these devices. Notebookreduce the symptoms of seasonal affective
producers ASUS have now started to include airdisorder. As a side effect of their research, they
ionizers in their computers.learned that high-density negative air ionization
Ions versus ozonecould have the same effect. Clinical research has
Ionisers should not be confused with ozonebeen published through Columbia University,
generators, even though both devices operate inAmerican Journal of Psychiatry/APA, 2006 and
a similar way. Ionisers use electrostatically chargedArchives of General Psychiatry, Columbia
plates to produce positively or negatively chargedUniversity, and New York State Psychiatric
gas ions that particulate matter sticks to (in anInstitute, 1998 and Journal of Alternative
effect similar to static electricity). OzoneComplementary Medicine, Columbia University
generators are optimised to attract an extra1995.
oxygen ion to an O2 molecule, using either aSee also
corona discharge tube or UV light. Even the bestElectrostatic precipitator
ionisers will produce a small amount of ozone, andHumidifier
ozone generators will produce gaseous ions ofNegative air ionization therapy
molecules other than ozone (unless fed by pureSeasonal affective disorder
oxygen, not air).[citation needed]References
At high concentrations, ozone can also be toxic to^ "Air ionizers wipe out hospital infections". The
air-borne bacteria, and may destroy or kill theseNew Scientist. Retrieved 2006-08-30. 
sometimes infectious organisms. However, the^
needed concentrations are toxic enough to^ "TITLE 21--FOOD AND DRUGS; CHAPTER
humans and animals that the FDA explicitlyI--FOOD AND DRUG ADMINISTRATION
demands ozone therapy not be used as medicalDEPARTMENT OF HEALTH AND HUMAN
treatment, and has taken action againstSERVICES; SUBCHAPTER H--MEDICAL DEVICES".
businesses that fail to comply with this regulation.U.S. Food & Drug Administration (FDA)
Pure ozone is a highly toxic and extremelywebsite. Retrieved 2006-08-30. 
reactive gas. A higher daily average than 0.1 ppm^ Kurtzweil P (1999). "Ozone generators generate
(0.2 mg/m) is not recommended and canprison terms for couple". FDA Consum 33 (6): 367.
damage the lungs and olfactory bulb cells directly.PMID 10628316.
Consumer Reports court case^ "Ozone: Good Up High, Bad Nearby".
Consumer Reports, a non-profit U.S.-basedEnvironmental Protection Agency (EPA) Website.
product-testing magazine, reported in OctoberRetrieved 2006-08-30. 
2003 that air ionizers do not perform to high^ "Ozone Generators that are Sold as Air
enough standards compared to conventional HEPACleaners: An Assessment of Effectiveness and
air filters. The exception was a combination unitHealth Consequences". EPA Website. Retrieved
that used a fan to move air while ionizing it. In2006-08-30. 
response to this report, The Sharper Image, a^ "Sharper Image pays $525,000 to end lawsuit
manufacturer of air ionizers (among otheragainst CU". Consumer Reports. 2006-08-06.
products), sued Consumer's Union (the publishers^ a b
of Consumer Reports) for product defamation.^
Consumer Reports gave the Ionic Breeze and^ Archives of General Psychiatry, 1998.
other popular units a "fail" because they have a1998;55:875-882
low Clean Air Delivery Rate (CADR). CADR^
measures the amount of filtered air circulatedExternal links
during a short period of time, and was originallyLook up ionizer in Wiktionary, the free dictionary.
designed to rate media-based air cleaners. TheNew Scientist - Air ionisers wipe out hospital
Sharper Image claimed that this test was a poorinfections
way to rate the Ionic Breeze, since it does notDo "corona discharge" devices alleviate asthma?
take into account other features, such as 24-hourOverview of electrofilter precipitator
a day continuous cleaning, ease of maintenance,NIOSH Immediate Danger to Life or Health
and silent operation. The U.S. District Court for the(Ozone) Documentation
Northern District of California subsequently struckIonic Air Purifiers and Smog
down The Sharper Image's complaint andThe Negative-Ion Myth
dismissed the case, reasoning that The SharperArticle regarding ionic air purifiers from the Los
Image had failed to demonstrate that it couldAngeles Times
prove any of the statements made by ConsumerAir ion behavior in ventilated rooms Indoor and
Reports were false. The Court's final ruling in MayBuilt Environment, 17 (2). pp. 173-182., Fletcher,
2005 ordered The Sharper Image to payL.A., Noakes, C.J., Sleigh, P.A., Beggs, C.B. and
$525,000 USD for Consumer Union's legalShepherd, S.J.
expenses.