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Reviews and General Information on Air Purifiers
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Air Flow, Performance and Air Changes per Hour

Guess what. I’m going to talk about the parameters you should consider before deciding on which air purifier to purchase for your home. An air purifier which is effective at collecting dust is perfect for people living in large cities or areas where there are plenty of these particles hanging around. On the other hand, those dealing with asthma and allergies will want to pay more attention to pollen and dust mite filtering capabilities.

There is a third group of people, namely pet owners who have a lot to gain from buying an air purifier. The one thing that makes all of the categories of people mentioned is the actual real-life performance of the purifier. That’s why I’ve decided to shed some light on things you should look for before shelling out your hard earned cash on a pricy piece of air purifying equipment.

How to Determine the Performance of an Air Purifier

There is a lot of information about the performance of air purifiers on the web. Sadly, most of those articles are about the efficiency and the performance of central HVAC units. As you’re in the market for portable air cleaners, these won’t help you much, so I decided to compile a short guide here.

Now, the three most important factors that play a role in the performance of an air purifier are the air flow rate, the number of air changes per hour and the unit’s CADR rating. I’m going to deal with the first two here, because the CADR rating deserved its own page).

Air Flow Rate

The air flow rate shows how much air passes through the purifier over a certain time period. Since air is a gas, it can be measured either by its volume or its mass. However, volume is what I’m interested in and so are the manufacturers that produce air cleaners.

Just so you know, purifier air flow is abbreviated to CFM or cubic feet per minute. For the most part, air flow is dependent on two factors: the power of the fan built into the air purifier, and the efficiency of the filter that’s inside.

Air Changes per Hour (ACH)

Put simply, ACH shows you how many times the entire volume of air inside a room is replaced during the course of one hour. Of course, the higher the number of changes the better! The number of changes usually varies anywhere between 1 and 7 (7 being the most efficient).

Regardless of your needs and the size of your home, I would advise you to consider units that are able to perform 2 or more air changes per hour especially if your home has a permanent source of allergens or contaminants. Just as an example, I used to live next to a small department store whose roof was right underneath my balcony.

The roof had a dozen massive air conditioning units mounted on it which produced an insane amount of dust, and a lot of this ended up inside my living space. As a result, I decided to look into an air purifier that would help (hence the website you see before you today).

When looking at various models, bear in mind how many air changes you would like per hour. Some unit’s are cheaper but are only efficient when they’re set on full power (which can be noisy). The more complex models will of course, have a higher number of changes on lower settings.

In Summary

As you can see, you are going to have to do some light math in order to arm yourself with all the necessary knowledge on air purifiers but trust me, it is worth it! Although, for the most part manufacturers should give you this information anyway, and if they don’t I’ve included it in the reviews I have on my site.

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