HEPA Air Purifier Consumer Guide Do you dread the thought of buying a HEPA air purifier online? Online air purifier information is often contradictory, blatantly false or even incomprehensible. Almost all of it is nothing more than calls to "buy me, buy me, buy me". You deserve a simpler, helpful air purifier guide. It shouldn't waste your time. That is what I hope you find in this guide to buying HEPA air purifiers. Please take a few moments to see if it answers your questions. All you have to lose is hours of pointing and clicking elsewhere. About HEPA Air Purifiers Portable HEPA filter air purifiers are designed to remove particles from the air like dust, pollen, pet dander, allergens, bacteria, and viruses. HEPA filtration is used in hospital operating rooms and intensive care units for just such purposes. HEPA filters are recommended by government agencies as helpful in controlling communicable diseases like tuberculosis, SARS, influenza, bird flu and other infectious agents. Most incorporate add-on technologies like activated carbon or germicidal UV lights to extend performance beyond what the HEPA filter media can achieve. When buying a HEPA air purifier you'll find models designed for specific problems. There are air purifiers available for particle filtration, smoke and odor removal or relief for allergy, asthma and multiple chemical sensitivities. Understand the Features of HEPA Air Purifiers HEPA Filters A true HEPA filter removes 99.97% of particles 0.3 microns in size. Many sites state "and larger" implying this is best-case HEPA filter efficiency. This shows a lack of understanding about HEPA filter material. The efficiency rating is not the best a HEPA filter can do, but the worst. To understand, picture a child throwing balls at multiple layers of chain link fence. Tennis balls do not pass at all. This represents particles larger than 0.3 micron. Ping-pong balls represent particles smaller than 0.3 micron. They are smaller than the gaps but lack the mass necessary to bully through the layers. An effect called diffusion causes particles to follow an irregular path. Picture a ping-pong ball corkscrewing through the air. It could never pass through the fence layers. A golf ball is small enough and has the mass to follow a more direct path to avoid being stopped by the layers of fencing. This represents particles 0.3 micron in size. This is referred to as the Most Penetrating Particle Size. A HEPA filter’s worst performance is at 0.3 micron. All other particles, whether larger or smaller are stopped with greater efficiency. This makes HEPA filter air purifiers ideal for removing allergens such as pet dander, dust mite residue, and pollen. These air purifiers are beneficial for those who suffer from respiratory conditions like asthma and allergies. Activated Carbon Filters Activated carbon filters are often used within HEPA filter air purifiers to remove odors and chemicals from the air. An activated carbon air filter contains specially treated carbon that has had millions of tiny pores opened up enabling it to trap gases by a process called adsorption. The adsorption occurs when chemicals are attracted to the activated carbon by a force known as the van der Waals force. An activated carbon filter is able to adsorb a wide range of chemicals up to 60% of its own weight. Once the carbon reaches its full capacity the filter needs to be replaced. How often will depend on the contamination level of the environment and how much carbon you have to begin with. This is why a HEPA filter air purifier that includes many pounds of activated carbon is recommended on this site. Activated carbon filtration is most often used to adsorb: The chemicals in smoke (from cigarettes and fireplaces) Formaldehyde and other volatile organic compounds (from furniture, carpet glues, paints, plastics, new building materials, etc.) Odors (pet, kitchen, urine, etc.) Pre-filters Pre-filters help trap large particles before they reach the HEPA filter. Having this pre-filter is a great benefit. It helps extend the time between filter changes and keeps the unit working more efficiently. Costs of HEPA Air Purifiers The price of HEPA filter air purifiers can range from the low $200s to more than $1,000. Deciding whether to choose the low-end or high-end model can be confusing. There are real differences in models, total capacity, actual system efficiency (not to be confused with the HEPA filter efficiency), and additional features like germicidal UV light or photocatalysis. The quality and quantity of clean air coming out of the unit is the basis of how each air purifier is different from one another. You don’t have to be an air purifier expert to figure out which unit is best for your needs, you simply need to consider clearly what your needs are. For example, you might ask the following questions to get the process started: Why am I getting this unit? Allergies, asthma, chemical sensitivity, odors? Is it for a single room? Or am I trying to clean all the air in my house? How big is my space (estimated square footage and consider high ceilings)? How long do I expect the unit to last? What is my budget? How much does it cost to maintain/replace filters? Do I want special features, like a “change filter” indicator light? Answering the above questions is a useful method to help you decide what type of unit you need to address your specific indoor air issues. Maintaining Your HEPA Air Purifier Maintaining an air purifier is an important part of keeping the unit working effectively, and there is a certain amount of cost and effort involved. Certainly air purifiers work for a time as a “turn it on and forget it” appliance; however, to get the most out of your investment you must keep the filters changed as needed. The cost of filters varies by unit and by type of filter, so it is important to check the price point on filters and the frequency of filter changes before you decide to purchase. Also, consider the environment in which you want the unit to function. For example, if you smoke in your home and you want a unit that will help to filter the smoke and the smell of the smoke, you will want a unit with an ample amount of carbon. You should evaluate the cost of replacing carbon filters as they become saturated. HEPA Air Purifier Size And Efficiency Air purifiers work best in the room they are placed in, and lose effectiveness the further you move away from that room. Single-room units cannot effectively clean the air in your entire house, as only the air that gets sucked into the unit gets cleaned. However, multiple units, or single-room units in combination with a whole-house unit is the best choice for total home air purification. When choosing what size unit to buy, you should consider the size of the area you want to clean. Ideally, your air cleaner should be able to provide five to six air exchanges per hour. However, any calculation of air exchanges per hour is only a foundation for helping you consider how a unit will perform in your home. This is because factors like the design of your home, which affects air flow from room to room, ceiling heights, the amount of furniture in your home the air must circulate around, the insulation of your rooms/home, and the amount of indoor air pollutants, such as pets and dust all impact an air purifier’s ability to clean the air. Air purifiers are rated by the cubic feet per minute (CFM) of clean air they deliver. You can determine how large an air purifier you need by determining the cubic feet of the room you wish to use it in. Multiply the length, width and height of your room. This gives you your room’s cubic feet. Divide that number by five; for the number of air exchanges you need to have. The final number is the CFM necessary to give you those five air exchanges. You should then look for air purifiers rated at that capacity or greater. Another consideration when it comes to efficiency is the fan in a unit. A general rule of thumb is the larger and stronger the fan, the more air the unit can clean and the faster it can clean it. A unit with multiple fan speeds will allow you to customize your air cleaner to better suit your needs. Choosing a unit with sufficient capacity to clean your air on a low setting will also mean quieter operation for you. Also, remember an air purifier can improve the quality of your indoor air, but it cannot eliminate pollutants completely. It won’t suck all the dust from your hard surfaces or prevent pollen from entering your house. However, it will help you to breathe easier, lessen your allergies, and give you a piece of mind that indoor air contaminants are minimized. The Elusive Silent HEPA Air Purifier You cannot find silent HEPA air purifiers because they must physically force air through the filter using a motorized fan. While HEPA air purifiers are not silent, the amount of sound they produce varies considerably. Many factors contribute to the sound level and whether you will be disturbed by it. The most common area air purifiers are placed is the bedroom. However, this is the number one area where people find the sound the most intrusive. The ideal way to have a quiet HEPA air cleaner is to choose a unit that can clean the room air at its lowest setting. Another option is to choose one of the Blueair air purifiers. These are not technically HEPA air purifiers but they achieve HEPA grade performance. They are a hybrid design that uses an ionizer ahead of the filter to boost collection efficiency of the filter. The filter itself offers lesser resistance to airflow than a standard HEPA filter. This lesser resistance means a lesser fan and quieter operation. Either way, it is important to understand that a sound will come from these units and it’s just a matter of finding the level of sound you are comfortable with. Many units list the decibel rating of the system at each fan speed. You can compare these ratings to other indoor appliances, such as the level of sound you hear from a normal box fan or the hum of the refrigerator, which can give you a point of reference. Sound is different to each individual, and even decibel results can sometimes be misleading as many things can affect sound level, such as position of the unit, carpeting, furniture, distance from the unit while it is running, fan speed, etc. Additional Features In HEPA Air Purifiers Many air purifiers special features that can greatly enhance your air cleaning experience. These features add convenience to your life and give you the additional options that allow you to optimize your air purifier to best fit your needs. Some of the special features to consider when shopping for your air cleaner: Casters for ease of mobility Remote control Digital controls Multiple fan speeds Handles Ease of filter change Filter-change indicator light If You Found My Site Useful You May Like These Featured Sites Natural Asthma Remedies provides current and useful information on natural asthma remedies as well as various natural asthma remedy topics. Great Asthma Tips Learn what causes and triggers asthma, more information like symptoms, treatment, the medicine and inhalers. Health Issues Tips You are in for a treat of straight to the point, valuablefitness and well being information, to ensure you maintain a long and healthy life. Return to Home Air Purifier Guide homepage from HEPA air purifier article. Custom Search