Allergies is an over reaction of the immune system in response the material that is consider as foreign substances. The foreign substance is called allergens. Allergies are caused by many factors such as dust mites, pollen, perfume, detergent smells, pet hair, etc.. 
There are many types of allergies such as food allergies, skin allergies, medicine allergies, animal allergies, allergy to particle that exposure in the workplace air, season allergy, perfume allergy and many more. Allergies to animals are ussually caused by a hair, salive and urine. Season allergy is usually caused by pollens that are emerging from surounding of your home. Allergies can be prevented in many ways such as maintaining the cleanlines of the room. The use of air purifiers for allergies, also can overcome allergies in the room. Maintaining personal and environmental hygiene. Avoid using clothes made of wool. Be careful in choosing foods and medicines that can cause allergies and avoid using air freshener.
For those of you who are indoors, you can use air purifiers for allergies. This device is able to capture and eradicate the allergens from the air. Allergens are usually derived from dust mites, pet hair and odor chemical and pollen. Dust mites are the organism that cause most allergiest because of dirty air.Allergies derived from pollen usually occurs on a seasonal basis. Pollen allergy symptoms most often include headache, sore throat, itching and sneezing. Allergic disorders usually occur frequently along with other disease such as asthma, ear infections, sinusitis and sleep disorders. Allergies can also cause bad chemicals that emit a stench like cigarette smoke, the smell of paint, bleach, detergents, air fresheners, perfumes and other chemicals.
To avoid the allergies actually prevent the allergen get into your body. You use air purifiers. 
There are a lot of choice of air purifiers available in the market. This device able to suck dirty air and release clean air to the room. The air purifiers for allergies often use ionizer that can produce ozon. This can kill allergens and increase the size of small particles in the air and pulling it into the filter. Excessive ozone is not good for human health if inhaled. Ozon can cause couhing, wheezing and other respiratory disorders.
The good air purifiers for allergies, must have some standard criteria. This standard include; the device have the certification from HEPA, it able to filter chemical gases and odors and it must free of ozone. The HEPA is the abbreviation of High Efficiency Particulate Arrest. The air purifier that has certified by HEPA could filter the air at least 99.7% air particles. The size of this particle up to 0.3 microns. There are many kinds of air purifiers for allergies. A good air purifier should also be able to filter the particles which cause by chemical odors and other caused by allergies gas. This can be known from it’s MERV ( Minimum Efficiency Reporting Value). MERV efficiency is describe by the scale of 1-20. 1 is the lowest effiency. It’s means the air purifier is not good. In addition, make sure your air purifier does not produce ozon.
