An air ioniser (or negative ion generator or Chizhevsky lamp ) is a high voltage device for ionizing (molecular) electrical air molecules. Negative ions, or anions, are particles with one or more extra electrons, giving a net negative charge to the particles. A cation is a positive ion that loses one or more electrons, producing a net positive charge. Most commercial air cleaners are designed to produce negative ions. Another type of ionizing air is the electrostatic discharge current (ESD) (balanced ion generator) used to neutralize the static charge. In 2002, in the obituary of The Independent newspaper, Cecil Alfred 'Coppy' Laws was credited as the inventor of a domestic air ioniser.
Air ionisers have been used to eliminate the occurrence of airborne bacterial infections and to reduce the buildup of static electricity in electronics.
Video Air ioniser
Ionic air purifier
Air ioniser is used in air purifiers to remove particles from the air. The air particles are attracted to the electrode in an effect similar to static electricity. These ions are de-ionized by searching for earthed conductors, such as walls and ceilings. To improve the efficiency of this process, some commercial products provide such surfaces inside the device. The frequency of nosocomial infections in UK hospitals prompted the National Health Service (NHS) to examine the effectiveness of anions for air purification, finding that recurrent acinetobacter infections in the air were removed by negative air ionization - the rate of infection fell to zero, an unexpected outcome. Positive and negative ions generated by air conditioning systems have also been found by manufacturers to disable viruses including influenza.
The SARS epidemic has sparked a desire for personal ionization in East Asia, including Japan (where many products have been devoted to containing negative ion generators, including toothbrushes, refrigerators, air conditioners, air purifiers and washing machines). There are no special standards for this device.
Maps Air ioniser
Ion versus ozone
Ioniser is different from ozone generator, although both devices operate in the same way. Ioniser uses electrostatically charged plates to produce positively or negatively charged gas ions (eg N 2 - or O 2 - ) that particulate matter attaches to an effect similar to static electricity. Even the best ionization will also produce a small amount of ozone - oxygen triatomik, O 3 - undesirable. The ozone generator is optimized to attract extra oxygen ions to the O 2 molecule, using a corona release tube or UV light.
At concentrations that do not exceed public health standards, ozone is found to have little potential for removal of indoor air contaminants. At high concentrations ozone can be toxic to air-borne bacteria, and can destroy or kill these sometimes infectious organisms. However, the required concentration is quite toxic to humans and animals that the US FDA declares that ozone has no place in medical care and has taken action against businesses that violate this rule by offering therapeutic ozone generators or ozone therapy. Ozone is a highly toxic and highly reactive gas. A daily average higher than 0.1 ppm (100 ppb, 0.2 mg/mÃ,³) is not recommended and can damage the lungs and bulbus olfactory cells directly.
Adverse health effects
A number of studies have been conducted on negative ion generators. A study shows that the ozone produced can go beyond the guidelines in a small, unventilated area. One study showed that ozone can react with other constituents, ie cleaning agents to increase pollutants such as formaldehyde (importantly, this study has the purpose of testing the use of indoor air cleaners and air fresheners and associated health risks as adverse health adversaries. air).
Consumer Report court case
Consumer Reports , a US-based non-profit product testing magazine, it was reported in October 2003 that air-ionizing does not work with a high enough standard compared to conventional HEPA filters. An exception is a combination unit that uses a fan to move the air while it is ionized. In response to this report, The Sharper Image, the aerial manufacturer (among other products), sued Consumer's Union (publisher
The United States District Court for the Northern District of California dismissed the case, arguing that The Sharper Image had failed to show that it could prove a statement made by Consumer Reports wrong. The Court's final judgment in May 2005 ordered The Sharper Image to pay US $ 525,000 for Consumer Union legal fees.
Electrostatic neutral identifiers in electronics
Air ionisers are often used in places where work is done involving static-electric-sensitive electronic components, to eliminate static charge accumulation on non-conductors. Since the elements are very sensitive to electricity, they can not be grounded because the discharge will destroy them as well. Typically, the work is performed on a special dissipative table mat, which allows very slow release, and under the flow of the ioniser.
See also
- Dehumidifier
- Electrostatic precipitators
- Humidifier
- Nebuliser
- Negative air ionization therapy
References
External links
- New Scientist - Air ionizers remove hospital infections
- Does the "corona discharge" device relieve asthma?
- NIOSH Documentation Comes Soon Life or Health (Ozone)
- How Can Air Purifiers Work?
- Ionic Air Purifiers and Smog
- Negative Ion Myth (archive)
Further reading
-
Fletcher, L.A.; Noakes, C.J.; Giring, P.A.; Beggs, C.B.; Shepherd, S.J. (April 1, 2008). "Air Ion Behavior in a Ventilated Room". Indoor and Built Environment . 17 (2): 173-182. doi: 10.1177/1420326X08089622.
Source of the article : Wikipedia
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