Ionic Air Purifiers, the Four Types of Ionization
Most people are unaware that there are at least four different distinct types of ionic air purifiers in use today. Ionizers in general have been around for many years.
Definition of an ion - an atom or molecule, electrically charged, which has lost or gained one or more electrons, making it either positively or negatively charged.
A simplified explanation of the process: The ionic purifier produces ions. The ions collide with and attach themselves to particles in the air (opposite charges attract). The particles attach themselves to other particles, collection devices or filters, or solid surfaces and are removed from the air. The exact process depends on the type of ionic air purifier used.
Ionization and ions are produced and are present in the air we breathe outside. Ions are measured by how many are present in a cubic centimeter or cm3. "Typical" clean air outside contains 3000 positive (+) and 4000 negative (-) ions per cm3. This amount can be influenced by a myriad of factors and is constantly changing and constantly replenished by sun, wind, and storms.
After detailed research it is my conclusion that the natural balance of ions outdoors is generally better than most of our indoor environments.
Have you ever felt like getting outside to get a breath of fresh air? Interestingly enough, some scientists point to +/- ions as part of the reason for outside air "feeling right". Unfortunately indoor air generally presents a problem for ions. In most cases the number of ions present is much less compared to outside air.
Sometimes there are too many positive ions and an imbalance occurs. Generally the imbalance leans towards the positive, but another problem could occur if too many negative ions are present. A balance is best, just like outside.
Ok, great you say, now what about cleaning the air with air purifiers....
The Four Basic Ionic Air Purifier Technologies:
1) Electrostatic precipitators and charged media filters: mainly passive technologies; most of the ionization occurs inside the air purifier. As air enters the purifier, an electronic charge is added to the particles. This charge is generally negative. The charged particles then pass into or over or through a metallic plate or special filter. The plate or filter has an opposite charge. This charge is generally positive. The particles ?stick? and can be cleaned by rinsing them off during cleaning or changing a filter. This is a decent way to clean air.
2) Single charge ionizers (+ or -): an active technology generally emitting just negative ions. This technology has some possible benefits as well as a host of possible negatives.
Benefits: does remove particles and some research has shown the health benefits of a surplus of negative ions. Negatives: particles tend to stick to other particles, walls, tables, everywhere ... and too many negative ions could upset the optimum balance desired between positive and negative ions in the air.
Many indoor environments have a surplus of positive ions ... this may be why some have reported great results with the added negative ions. Common sense points to an unbalance developing when you keep adding the negative ions either in the short or long run. You may have also heard of "black wall syndrome".
This is where many particles are negatively (-) charged by ions and then are attracted and "cemented" to a positively (+) charged wall. This is interesting interior decorating for sure. This is not the best way to clean the air with ionization, but generally the most common and least expensive.
3) Double charge ionizers (both + and -): an active technology that emits both positive and negative ions. This technology is very effective and minimizes on the "black wall syndrome". It also maintains a better balance of negative and positive ions. Oppositely charge particles are attracted to each other and by clinging to each other, form larger particles too heavy for the air. They drop out of the air.
They are eventually vacuumed or dusted up or picked up by a furnace filter. This is an excellent way to remove particles. This technology is available from only a handful of companies.
4) RCI (radiant catalytic ionization): an active technology that is currently available from only a few companies. RCI or an equivalent is a combination of technologies wrapped in one. These technologies generally include UV, double charge ionization (+ and -), as well as a few other proprietary types distinct to each company. The documented results are impressive. This technology is available from only a handful of companies.
Buying Considerations: Do your homework.
Because there are several versions of the ionization technology, it can be hard to select the right one. Stay away from single charge ionizers all together. Even within the other technology types you need to search diligently for a quality ionic air purifier. Realize that there may be only a handful of companies with a "trust factor like" track record.
Be wary of the others as marketing hype as well as copy cats and small time vendors exist. Always buy from an established company with a lengthy track record...Sharp kc 830u!