The 10 Worst Mistakes To Avoid When Buying Air Filters

Air filters are important for maintaining good indoor air quality and promoting overall health and well-being in our homes. An air filter for home removes airborne pollutants like dust, pollen, mould, mildew, and other allergens from the air, ensuring the air you breathe is safer and healthier. Yet, you can only reap all these benefits if you choose the right air filter for your air purifier.

Air filters come in all shapes and forms. They are built from different materials and have a unique ergonomic design to improve their air filtration efficiency. Some advanced air filters were initially used in hospitals and research labs, where indoor air quality is important, before they found their way into residential home appliances. 

 

What are the 3 different types of air filters?

 

1. Fibreglass Filters

● What: Electrostatic, disposable filters that catch large particles (dust, pollen).

● Best for: Budget buyers (but misses tiny pollutants).

 

Morris tip: "If you’re asking ‘Should I get an air purifier?’, fibreglass alone won’t cut it for allergies."

 

2. Pleated Filters 

● What: Folded fabric (polyester/cotton) with better particle capture than fibreglass.

● Best for: Mid-range needs (mould, pet hair).

● Morris match: Our pre-filters use pleated tech to extend HEPA lifespan.

 

3. HEPA Filters (Gold Standard) 

● What: Removes 99.97% of particles ≥0.3µm—dust, viruses, even smoke.

● Best for: Allergy sufferers, pet owners, health-focused homes.

 

Why Morris? Our MOR-AP01 & MOR-AP02 use medical-grade H13 HEPA—the highest standard. Shop HEPA H13 Purifiers.

 

 

"Should I Get an Air Purifier?"

✅ If you want...

● Real protection: Skip fibreglass—only medical grade H13 HEPA tackles tiny pollutants.

● Whole-home cleaning: The Morris MOR-AP02 model covers 237 sq. ft. with 3-stage filtration.

● Pet/dust relief: HEPA + carbon filters in our purifiers trap dander and odours.

 

Compare Morris HEPA Models → Find Your Fit

 

Which is best air filter to buy?

Air filters are essential in ensuring the air we breathe is clean and free from harmful particles such as dust, pollen, and allergens. However, getting the right air filters for home air purifiers can be confusing for a first-time buyer. To ensure you make the right decision when window shopping for air purifier filters, here are the ten worst mistakes to avoid when buying air filters:

1. Choosing the wrong filter size

Getting the size of the air filter right is crucial in ensuring its effectiveness when installed in an air purifier. Always measure the dimensions of the air filter slot in your air purifier to ensure you get the right air filter for it. Fortunately, most air purifier brands in the UK do sell replacement air filters for their products. It pays to get a few extra filters with your first air purifier purchase to ensure you are prepared for the next filter replacement.

2. Overlooking the MERV rating

The Minimum Efficiency Reporting Value, or MERV, refers to an air filter's ability to remove particulate matter, 0.3 to 10 microns in size, from the air. Air filters with a high MERV rating are more efficient in filtering out air pollutants. If you are dealing with a lot of indoor air pollution, going for a higher MERV air filter is better. Note, however, that high-efficiency air filters have a shorter lifespan compared to filters with a low MERV rating.

3. Choosing the wrong type of filter

There are various types of air filters, including ioniser filters, activated carbon filters, HEPA filters, and so on. Each of these filters has specific features and suits different applications. So, choosing the right one for your needs is crucial.

●Ioniser air filters release negative ions into the air that clamp onto airborne particles. These are usually tiny particles that float in the air and are invisible to the eye. Ioniser filters may not be that great for large particle pollutants.

●Activated carbon filters are good for eliminating smoke and unpleasant odours. Such filters are also ideal for removing volatile organic compounds from the air. Similarly, this type of filter may not be efficient at filtering out large particles in the air.

● HEPA filters are the industry standard because they purify air from all types of impurities. Medical-grade air purifiers are handy when removing both tiny particles (up to 0.3 microns) and large particles (up to 100 microns).  

4. Dismissing the airflow rating

Airflow rate refers to how quickly air flows in and out of an air purifier and is measured in cubic feet per minute, or CFM. The higher the CFM rating, the higher the air flow capability of an air purifier. If you are in a room that needs frequent air purification, you will need an air purifier with a higher CFM. The airflow rating also determines the amount of air a filter can handle. Choosing a filter with a low airflow rating can lead to reduced efficiency and increased wear and tear on your HVAC system.

 

 

5. Ignoring the air filter lifespan

All air filters have a shelf life. How long an air filter lasts depends on usage and room conditions. An air filter that works in a humid environment would work better than one in dry conditions. Ignoring the air filter can reduce the efficiency of your air purifier, and possibly increase replacement costs.

Most air filters have a lifespan of 12 months if used for about 4 hours a day. Fortunately, most modern air purifiers have an inbuilt filter replacement indicator that will alert you when the air filter has expired.

6. Not replacing air filters regularly

Not replacing your air purifier’s filter will reduce its effectiveness. As mentioned before, ignoring the warning light to change the filter can cost you in terms of poor indoor air quality and increased energy consumption.

7. Not properly maintaining the air filter

Some air filters for air purifiers at home need more maintenance than others, such as cleaning or washing. Improper care of an air filter, thus not understanding its maintenance requirements, can lead to reduced efficiency and increased replacement costs.

8. Choosing cheap over quality

While air filter pricing is important, it should not be the only factor that determines if you buy a filter or not. Cheap is expensive, and choosing a cheaper filter can cost you more down the road in terms of filter replacements or air purifier repairs. Go for quality air filters that are air filters. Choosing a cheap filter may save you money in the short term, but it could lead to increased costs in the long term.

9. Not considering the environment

Environmental factors like high humidity and temperature can diminish the efficiency of air filters and, subsequently, their lifespan. You may have to use a dehumidifier and a portable fan in such conditions to reduce the air purifier running costs and increase the longevity of the air filter.

10. Lack of prior research and professional advice

If you are unsure about which air filter to go for, seek the help of an air purifier expert to help you make an informed decision. HVAC professionals are knowledgeable about the various types of air purifiers and their respective air filters. Also, research the type of air purifier you own and the filters that are compatible with it.

 

 

Which air filter removes the most dust?

Between the fibreglass, pleated, and HEPA filters, the HEPA air filter removes the most dust from the air given its unique design and functionality. Household dust is a collection of many small particles that get airborne and ruin indoor air quality. This includes:

1. Dead skin cells

Humans shed millions of dead skin cells daily, and these dead skin cells make up a large portion of household dust.

 

2. Pet dander

Pet dander comprises dead skin cells, hair, and saliva from our pets that contribute to accumulated dust.

3. Fibres

Fibres from fabrics, upholstery, carpentry and all other sorts of fibres in the home all contribute to household dust.

4. Pollen

Pollen from plants floats into our homes via open windows and settles on surfaces, adding to the dust present.

5. Dust mites

Dust mites are microscopic insects that thrive in household dust, feeding on dead skin cells.

6. Insect debris

Dead insects and insect excrement also add to household dust.

7. Mould spores

Mould thrives in damp areas of the home and releases spores in the air, which combine with household dust.

 

8. Bacteria and viruses

Bacteria and viruses are ever-present in household dust and can trigger illnesses when inhaled by humans and pets.

The best air purifier for household dust is one fitted with a HEPA air filter. This is because a HEPA filter has a dense, meshy construction that can trap all sorts of airborne particles, even those that are 0.3 microns small. Moreover, most HEPA air purifiers now feature a complex filtration system that features a HEPA filter and other crucial filters like an activated carbon filter and an ioniser filter.

Although a HEPA filter is efficient in removing large and small airborne pollutants, it is not as effective in dealing with odour. This is where an air filter for smoke and other noxious gases comes in handy. The activated carbon filter eliminates cigarette smoke, weed smoke, kitchen smoke, and any other source of smoke in your home.

 

 

Also, a carbon filter is necessary if you want to get rid of volatile organic compounds, or VOCs, in your home. These are poisonous chemical fumes like formaldehyde and methyl tert-butyl that originate from paint thinners, petroleum products, hydraulic fluids, and cleaning products. VOCs are harmful gases that trigger respiratory problems and are carcinogenic (can cause cancer).

 

Do air purifiers make a difference?

Air purifiers can make a huge difference in the indoor air quality of your home or building. They remove harmful airborne pollutants and allergens in the air which ensures the air you breathe is clean and fresh. The scientific research "Effects of the use of air purifier on indoor environment and respiratory system among healthy adults" has proven that an air purifier helps improve human health in everyday life by reducing the levels of air pollutants in the home. This includes pollutants such as household dust, pollen, mould, mildew, unpleasant odours, and volatile organic compounds (VOCs).

 

However, how effective an air purifier is will depend on several factors. It includes factors such as the size of the air purifier, the type of air filter used, and the level of pollution in the air. You also have to consider other things like room ventilation and air leaks in your home.

 

For instance, a small HEPA air purifier will be effective in a room no larger than 40 sq. ft. The same air purifier may not be as effective in rooms measuring 200 sq. ft. or more. An air purifier with a low-quality filter or only one filter may not be efficient enough to remove the broad range of airborne particles in your home. The wrong-sized air purifier and low-quality filter may not do much for a room with a high air pollution rate.

 

Also, while air purifiers can help improve indoor air quality, they are not a substitute for proper home ventilation or other measures for controlling indoor air quality. To maintain good indoor air quality, it's important to properly ventilate your home, reduce air leaks and pollution sources, and maintain optimal indoor humidity levels.

 

In conclusion, an air purifier is a handy tool for improving indoor air quality. However, choose a high-quality unit and use it with other air quality control measures for the best results.