Ionizer Function

Ionizers produce electrically charged atoms (or ions). Because atoms are electrically neutral (with same number of positive and negative charge), ions are produced by making them loose or gain some of this charge. Gaseous contents, as well as solid particles and vapors are also similarly ionized by attaching excess positive or negative charge to them.

Scientific Principle

• Primary function of any ionizer is to produce positive or negative ions, which in turn may be used in various applications. While ions can be produced in many ways, most common and old industrial method is to use the principle of corona discharge. Here, electric current develops from a curved electrode immersed in a neutral electric field with a high potential gradient. This results in ionization of surrounding fluid, making it conductive and discharging ions. Positive and negative ions can be produced this way, depending on electrode polarity.

  Ions thus produced may recombine to form neutral fluid particles or get released. When ions are slowed down, dissolved or suspended in the air or water, impurities such as pollutants, dust, pollen, smoke, fume and aerosol start clustering around them. This however makes them grow and become heavy, eventually neutralizing and settling them down.

Types

• Ionizers are broadly classified as active or passive. In passive ionizers, metal tips are grounded to the earth. These have limited effect and are only deployed in combination with an active ionizer, with the purpose of knocking down an excessively large charge. Alternatively, active ionizers produce ions and neutralize the ambience. Further, air-assisted active ionizers are used to increase the effective range of ions by blowing compressed air, which increases the distance traversed by the ions within the ambient fluid. Another classification is based on whether the ionizer produces positive or negative ions. Further, ionizers are classified on the basis of fluid they ionize, such as air or water.

Nomenclature

• Ionizers can also be named after the material used, such as tinsel or static string.

Uses of Ionizers

• Ability of ionizers to remove even extremely small particles from air or water is a valuable health advantage, especially because human immune system is not able to purge them from the inhaled air. Research also shows that high concentration of negative ions is useful in the treatment of "seasonal effective disorder." Though there is still no conclusive scientific evidence that reduced water that is produced by a water ionizer is considered good for humans as it potentially acts as an anti-oxidant, thereby slowing age related problems and preventing disease.

Potential Harms

• Although ionizers find a variety of uses, badly designed ones (specifically air ionizers) are a potential health hazard, as they produces ozone and nitrous oxide. This can cause respiratory and ophthalmic problems, or even more serious health problems if the toxicity levels of these gases exceed an acceptable threshold.