Air purifiers purify the air by eliminating dust, pollutants, allergens, contaminants, smoke, mites, bacteria, virus, pollen, molds, odors, gas, etc. With increasing indoor air pollution, the necessity of having an air purifier has amplified. They are a great boon for patients suffering from asthma and different types of allergies. Today, they became a necessity for every home.
Many brands with different specifications are entering the market, making it difficult for a consumer to choose the best one. Before finalizing a product, one should make sure that he/she is aware of the technology used in it and the concerns it addresses.
Types of technologies
The technology used in air purifying is basically categorized into two categories – Active and Passive. However, there are some purifiers which make use of both the technologies.
1. Passive technology
Passive technology involves purifying air by drawing it to the purifier. The air drawn passes through the filters, present in the purifier, thus purifying the air from contaminants, micro-organisms, allergens, dust particles, pollen, odors, gas, etc. Some of the passive technologies include:
• HEPA and generic filters – both used to filter solid particles from air
• Activated carbon air filters – used to remove chemical compounds and odors
• Electrostatic precipitators – used to filter very small particles
• UV filters – used to kill micro-organisms in the air
The purifiers using passive technology need to have filters compulsorily.
2. Active technology
Active technology is a technology, wherein air is purified outside the purifying unit by producing some kind of effect in the air. Active air purifiers are of two types. They are:
• Ionizer purifiers produce ions, which attach to particles and eliminate chemical compounds, dust particles etc. from air
• Ozone generators alter molecules 空氣清淨機 of oxygen and turn them into ozone; thus destroy micro-organisms and remove odors and gases from air
3. Active and passive technologies
This is a combination of both active and passive technologies and the purifiers with this technology are more efficient than purifiers with each of the individual technologies.
Concerns they address
Before buying an air purifier, one should be clear about the purpose of his purchase and needs to check if it is fulfilling the same or not. There are various concerns, which an air purifier needs to address.
Allergies: Most of the city dwellers are exposed to dusty environment. The dusty air consists of many tiny dusty particles like sand, tiny stones, pollen of plants, etc., which are allergic to most of the people. As most of the allergens are solid particles, an air purifier whose filters are efficient enough to filter these allergens should be bought.
Asthma: Asthma is a chronic breathing disease, which exaggerates further on breathing the air filled with impurities. Air purifiers should not only be able to filter the air from impurities but also should be able to oxidize the air.
Odor: Modern day homes have a very limited ventilation option. Hence, the circulation of air in the home becomes difficult. Due to the stagnation of air, typical odor may develop. Odors may also be due to various reasons like painting, cooking, burning, etc. In such cases air purifier should be able to eliminate odor from the air.
Smoke: Smoke is a major concern in the houses on the road sides or in the industrial localities. Other reasons for smoke in indoors are cooking, burning, etc. Smoke contains a thick amount of pollutants capable of affecting the health of the human beings. An air purifier should be able to effectively clear all the thick solid particles present in smoke.