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Factors to Consider When Buying an Air Purifier

What do you need to check before buying an air purifier?

Well, before you buy an air purifier, several concerns must come to mind. For example, what kind of pollutants am I dealing with? Can they be cleared with a single system or do I need multiple methods of air purification? These questions help you to examine various available options critically and make a sensible decision.

Factors to Consider When Buying an Air Purifier

This article seeks to explore the most common pollutants in our homes and how to get rid of them. Also, we will reveal all the features to look for in an effective air purifier.

The most common air pollutants

Every home harbors pollutants – odors and smoke from cooking fumes, firewood and cigarettes are the most common. There are also microscopic airborne allergens like pet dander, dust mites, mildew, pollen, mold, bacteria, and viruses. All these allergens are health hazards and need to be eliminated.

Therefore, you need to get the best air purifier possible. For example, mold and mildew grow and multiply in wet areas such as the kitchen, garage, store, and laundry rooms. Their allergy symptoms resemble those of a common cold.

Most homes also have cats, dogs, and other furry pets that are responsible for odors, pet hair, and dander. These mostly trigger skin and eye infections with symptoms like itchiness, watery eyes and skin rashes. So, if you can get your hands on the best air purifier for pets, you will be fine.

Other allergens are dust particles, dust mites, and pollen that mainly spread during dry and windy seasons. As much as they are external pollutants, they are also harbored in homes due to limited air circulation. Their allergic reactions include nasal congestion, dry cough, sneezing, and running nose, among others.

Five factors to consider when buying an air purifier

Like most other home appliances, an air purifier is a long-term kind of investment. So, you don’t want to make a terrible decision of which unit to purchase. Here are the main considerations to make before settling on a particular air purifier.

1. What are the main pollutants you want to deal with?

Depending on where you live and how you live, there has to be the main pollutant you want to eliminate. Let’s take the example of pets. If you have pets, regardless of whether you live in a warm or cold area, the pets must shed hair and dander. Dirt from pets is comprised of pets’ waste – urine and feces, microscopic skin flakes and saliva.

Pet dander also tends to release an odor. So, as you choose your air purifier, you need one that not only tackles the primary issue of pet dander but also deals with the odor. The odor could also be emanating from waste, kitchen fumes or cigarette smoke.

If your home is inhabited by mold, mildew, bacteria, and viruses, you want to ensure the purifier you choose can deal with these specific pollutants. Fortunately, you can get air purifiers that are allergen-specific. You can read more in our best air purifier for mold review.

2. Filtration system

Filtration is the core of any air purifier. It is by filtration method that airborne particles and other allergens are captured and eliminated. This leaves you with crisp clean air in your home or office.

The main and most reliable filtration system is HEPA filtration. Some manufacturers refer to it as True HEPA. A HEPA filter features highly absorbent and fibrous material that enables the capturing of air particles as small as 0.3 microns in diameter. Therefore, it has the highest efficiency level at 99.97% capture-rate for all allergens.

Note that some manufacturers may label their filters as HEPA-like. However, always go for one that is “HEPA” or “True HEPA”.

Other filters include pre-filter, activated carbon, ionizer, and photocatalytic oxidation. Activated carbon is an efficient odor absorbent filter. It takes care of cigarette smell and smoke, firewood smoke, fumes, vapor from chemicals, mold, and mildew.

On the other hand, photocatalytic oxidation compliments activated carbon in eliminating odors as well as chemicals. Lastly, the ionizer helps in settling particulates from the air.

3. Room size

Air purifiers have varying capacities. Depending on how fast the fan speed is, the manufacturer determines the purifier’s capacity in terms of space covered. In some instances, the physical size of the appliance also determines its capacity.

If an air purifier has ionizers, it is capable of dispersing negative ions throughout the room and is therefore suitable for larger rooms. Additionally, it’s recommendable to use a purifier with larger coverage if the room is highly polluted or congested. An open area requires less power to clean.

4. Convenience (e.g. automatic sensors/alerts change of filters/noise level/ lighting)

While you can access a more affordable manual air purifier, an automatic one can surprise you at the level of efficiency it offers. Also, most modern purifiers feature automatic air quality testing using smart sensors.

These smart sensors rate and adjust the fan speeds according to the quality of the air in the room. So, you can be sure that your indoor air is well taken care of round the clock whether you are present or not.

Another convenience is having alerts for the filters’ lifetime. Some units use a beep while others use LED lights to communicate when it’s time to replace filters. This ensures that the air purifier works throughout as long as you observe the replacement schedules.

While operating at high speed, air purifiers tend to be noisy. So, look out for the lowest decibels possible. This helps to have un-disturbed sleep, especially at night when it’s all quiet. Also, LED lights help to communicate the status of the air. However, they can be irritating to the eyes especially at night. Therefore, an air purifier with an LED on/off option or automatic dim feature would be a better pick.

5. Cost (buying and maintenance)

Finally, everything boils down to your budget. The appliances in the market have different capacities yet some cheaper models perform better than the more expensive ones. This could be influenced by multiple factors like the brand.

So, I would suggest you make your decision based on quality and capacity rather than factors such as the brand.

Air purifiers also come with additional costs such as filter replacement. Some filters can last for as long as a year while others require replacement every 3 to 6 months. Considering air purifiers ill-perform while using worn out or dirty filters, this becomes a major consideration during purchase.


There are other minor factors to consider while choosing an air purifier. For instance, you can consider the size of the appliance and how it blends with your furniture. However, you don’t have to milk your bank account dry to get a good air purifier.

Remember that the market is now larger than ever. So, you can get an air purifier that meets your specific needs but within your budget. This guide will definitely help you know what to look out for and, therefore, make the right choice.

Happy shopping!

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