Frequently Asked Questions

From “what is a MERV rating?” to “why do I need an air filter?”, we hear lots of questions about filters and air-quality here at Duststop, so we thought we’d break them all down for you.

What is a MERV rating?

Although a MERV rating (which stands for Minimum Efficiency Reporting Value) might sound complicated, it really just tells you how effective your air filter is in comparison to other air filters on the market.

For residential settings, like your home or office, MERV ratings go from 1 to 13, with MERV 13 being the highest rated filter for a domestic environment.

(ASHREA Tested MERV ratings actually go up to MERV 16, but 13-16 are usually for factories and medical environments with systems that are designed to handle the airflow restriction these filters will cause.)

What difference does a MERV rating make to my air quality?

The MERV rating indicates how effective the filters are at removing different size particles from the air you breathe.

At the top end, MERV 11 to 13 removes the most particles and contaminants — from the visible ones like smoke and dust to pollen and other microscopic allergens — from the air you breathe, while MERV 1 filters are good for providing maximum airflow while still removing some of the larger particles like dust and pollen.

On a more scientific level, MERV 11 to 13 filters can capture particles from 10 microns to as small as .30 microns from the air, while MERV 1 filters can capture particles that are closer to 10 microns in size.

For scale, 100 microns is about the thickness of a human hair, so even MERV 1 filters can capture particles that are very small.

Is a higher MERV rating always better?

It’s a common misconception that you should always choose the filter with the highest MERV rating.

And, on the surface, it makes sense: a higher MERV rating means fewer particles and contaminants in the air, which equals better air quality.

However, as you increase the MERV rating, you decrease the size of the holes that allow air to flow through your HVAC filter.

If your system wasn’t designed to handle a filter with a high MERV rating, this can reduce the air flow into your home, worsening the air quality and — in some cases — causing damage to your furnace.

Can you remind me when my filter needs changing?

We sure can! Just head to and enter your details and we’ll send you an email every time your filter needs changing.


What happens if I don’t change my air filters as needed?

When you have old or dirty air filters, your air is probably not getting circulated as efficiently as possible, which means that your system is costing you more to operate and your risk of damage is increased.

To make sure that your system is operating as efficiently as possible, make sure you change them as needed.

How often should I change my filters?

All of our air filters have different recommendations on the packaging to indicate how often they should be changed. This recommendation is based on their Size, MERV rating and efficiency under average household conditions.

You may want to change the filter more frequently if:

  • You are remodeling or there is any other kind of construction work in progress
  • There are pets in the home
  • You have a wood stove in your home
  • There are smokers in the home

What contributes to the poor indoor air quality in your home?

Great question!

The answer has a lot to do with the way that modern homes are built. Essentially, modern homes are designed and built to be energy efficient. As such, they trap a lot of air inside the building and stop it from escaping.

So, while this is good for your energy bills and the planet, it’s not great for your air quality, as your home can’t breathe naturally.

Because of this, pollutants and allergens — like pet dander, pollen, dust and mold — become trapped and recirculate around your home, rather than naturally finding their way outside.

Your air filter helps remove these particles from the air and improve the quality of the air you breathe.

Can an air filter help with dust mites?

Certainly! Air filters help remove dust from the air in your home, removing the dust mites’ main food source from your home. The less dust in the air, the fewer dust mites you’ll have.

Will an air filter help with dog hair?

Definitely! An air filter helps remove dog hair from your home’s air by trapping the hairs in the filter and stopping them from recirculating around your house.

Can an air filter help with asthma and respiratory problems?

Yes, an air filter can help with asthma. Air filters are designed to help remove some of the particles and allergens that cause asthmatic symptoms from the air you breathe.

If you have asthma, be careful not to use an ionic air filter, as these can make your asthma worse.

Can an air filter help with allergies?

Yes indeed!

Air filters are designed to help remove some of the allergens from the air you breathe and stop them recirculating around your house. As long as you make sure to change or clean your filter regularly, an air filter can help improve allergy symptoms.

Are your air-filters eco-friendly?

They are!

Whenever possible, we’ll use recycled or recyclable materials to make the air filters that you use in your homes.

In fact, over the last few years, we’ve consistently saved the equivalent of 13,541 mature trees (that’s enough trees to fill 8 football fields every twelve months) by using recyclable waste in the production of our product packaging.

We also use 100% post-use recycled waste paper fibres to make frames around our filters, taking an extra step to make sure our filters are as eco-friendly as possible.

Contact Us

If you have any questions about Duststop or our air filters, please don’t hesitate to get in touch with us.

Tel (519) 882-2800
Toll Free (877) 477-7781
Fax (519) 882-3040