What are MERV ratings and why do they matter?
Minimum Efficiency Reporting Value (MERV) ratings show how effective a filter is at removing particles, allergens, and pollutants from the air. It’s a scale from 1 to 16, and the higher the number the more effective the filter is. A good MERV rating is between 9 and 12, as these filters remove around 75% to 90% of particulates from the air.
What is a MERV rating, and why does it matter?
The MERV rating, or the minimum efficiency reporting value, is a measurement of how effective an air filter is at removing dust and debris. MERV ratings range from 1-16 with higher ratings corresponding to smaller filter pores and thus greater air filtration. For example, an air filter with a MERV value of 16 will remove exponentially more air contaminants than a filter with a MERV value of one.
What MERV rating should I use?
What is a MERV Rating?
- MERV 1-4: Carpet fibers, cockroach debris, dust mites, pollen, sanding dust, spray paint dust, and textile fibers.
- MERV 5-8: Dust mites, dusting aids, fabric protector, hair spray, mold spores, and pet dander.
- MERV 9-12: Humidifier dust, nebulizer droplets, legionella
- MERV 13-16: Bacteria, saliva droplets, and dust from smoke.
What is a MERV rating and what does it mean?
MERV stands for Minimum Efficiency Reporting Values. The MERV rating measures a filter’s ability to stop and contain airborne particles between 0.3 and 10 microns large. This is the range that includes dust, mites, pollen, mold spores, and can even include some microbiology like bacteria cells in the are. MERV ratings range from 1-20.
Is MERV 11 too high?
In most cases, a MERV 11 air filter isn't too high for residential use. Generally speaking, anything under a MERV 13 air filter should provide very efficient air purification in a home without impacting airflow.
Is MERV 11 or 13 better?
MERV 11 furnace filters have a particle arrestance of a little over 90%. In comparison, MERV 13 HVAC filters have a particle arrestance of around 98%. Naturally, it is significantly more efficient. MERV 11 rated air filters are ideal for those who live in a moderately polluted area, have mild allergies, or own a pet.
Is MERV 13 too high for home?
MERV 13 air filters are the highest-rated air filters for home use. Any air filter with a rating higher than 13 will restrict air flow to the point of which could cause damage to your HVAC system, resulting in an added expense to fix it.
What MERV rating is best for home use?
between 8-10In general, the best MERV rating for a home is somewhere between 8-10. These filters will capture a large portion of the airborne particles and improve indoor air quality without making your energy costs rise significantly.
Will MERV 11 hurt my furnace?
The short answer is that it can, but it's not really an issue except under extreme circumstances. Most modern HVAC systems have no problem working with higher MERV filters, which is why millions of homeowners depend on them.
Is there a downside to high MERV filters?
Wrong. While the highest MERV ratings are the most effective for air quality, they can harm your HVAC system. A higher MERV rating means a higher resistance, which means less airflow. When researching HVAC systems, airflow will come up a lot.
Does MERV 13 filter Covid?
What kind of filter should I use in my home HVAC system to help protect my family from COVID-19? Minimum Efficiency Reporting Values, or MERV, reports a filter's ability to capture particles. Filters with MERV-13 or higher ratings can trap smaller particles, including viruses.
Is MERV 8 or 11 better?
A MERV 11 rated filter captures 85% or better of particles between the sizes of 0.3 and 10 microns. This may not seem like a significant difference compared to the MERV 8 filter, but a MERV 11 is also more capable of capturing between 65% and 79% of smaller particles.
How many MERV Can my furnace handle?
MERV 13 is the highest MERV value safe for residential furnaces; the higher ratings are used primarily in commercial units. If you are wondering what MERV to try, keep these recommendations in mind; ASHRAE recommends MERV 6 or higher. US Department of Energy recommends MERV 13.
What MERV rating is best for furnace filters?
MERV 13 air filters are considered the best overall for residential HVAC systems.
What is the most common MERV rating?
In the U.S., the MERV 8 filter has proven to be the most common filter on the market.
How often should Merv 8 filters be changed?
every 3 monthsFor Merv 8, 11 and 13 filters, we recommend that you change your filter at least every 3 months, however changing your filter every 2 months provides better filtration which provides healthier and cleaner air in your home.
Are MERV 13 filters worth it?
A MERV 13 filter is a step in the right direction and captures more particles than a typical MERV 8 filter. However, it is not as good at capturing small virus sized particles like a HEPA can. A MERV 13 will trap less than 75% of air particles that are 0.3-1.0 micron in size (the coronavirus is 0.1 microns).
Are MERV 13 filters effective against coronavirus?
What kind of filter should I use in my home HVAC system to help protect my family from COVID-19? Minimum Efficiency Reporting Values, or MERV, reports a filter's ability to capture particles. Filters with MERV-13 or higher ratings can trap smaller particles, including viruses.
How often should MERV 13 filters be changed?
For Merv 8, 11 and 13 filters, we recommend that you change your filter at least every 3 months, however changing your filter every 2 months provides better filtration which provides healthier and cleaner air in your home.
What is the most common MERV rating?
In the U.S., the MERV 8 filter has proven to be the most common filter on the market.
What is the Minimum Efficiency Reporting Value (MERV) Rating on Filters?
MERV stands for Minimum Efficiency Reporting Value. Or in English, “how effective is your air filter?”
What is the difference between MERV 13-20 and MERV 7-12?
In general, most residential systems can adequately remove airborne contaminants with a filter rated MERV 7-12, while MERV 13-20 is typically found in hospital and pharmaceutical manufacturing settings. Advertisement.
What is a Merv 13 filter?
MERV 13 filters, for example, also scrub out bacteria, tobacco smoke, auto fumes, insecticide dust, pet dander, and more., which is why it’s the recommended rating of the ASHRAE.
What is the best rating for HVAC?
According to the ASHRAE, the best rating for residential HVAC systems is MERV 13. But before you upgrade your filter, make sure your specific system can accommodate that rating. A higher MERV rating often means lower airflow, which can cause the system to work harder—use more energy—to do its job. If your home HVAC system is not capable of handling MERV 13, opt for a filter with the next highest rating possible.
What is MERV 17-20 used for?
MERV 17-20. Commonly used for facilities that house pharmaceutical manufacturing, orthopedic surgery rooms, radioactive and carcinogenic materials. Controls all of the particulates listed for MERV 1-16 above, in addition to virus carriers, carbon dust, sea salt, combustion smoke, radon progeny, and microscopic allergens.
How often do you change a Merv filter?
When you’re changing filters four times a year, that really adds up. So if you’re working with a builder to design a system, keep that in mind.
Is MERV 13 efficient?
Though MERV 13 is suggested by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), it might not be the most efficient choice for some residential HVAC systems. In fact, MERV 11 may even be too restrictive.
Why is a higher MERV better?
Here are the top three reasons why you needn’t bother going with a higher MERV: 1. Higher MERV filters block air flow, which makes it more difficult to sufficiently heat or cool a room because the fan can't properly circulate the air. Because they have tinier holes through which particles can pass, they get clogged up faster than lower MERV rated ...
What does MERV stand for in a house?
Remember, MERV stands for Minimum-Efficiency Reporting Value and measures the efficiency with which filters remove particles of certain sizes.
Why do you have to change MERV filters more often?
So, you have a double whammy: not only are you spending way more money than you need to per filter, you have to change them more frequently because they get dirtier faster.
What MERV Rating Is the Best?
The MERV rating tells you what the furnace filter can block out, but understanding what each of the numbers means will help you decide which rating is right for you.
How much does a MERV cost?
But they may be adequate for households without allergy concerns. These are available in MERV ratings 2-4. Expect to pay anywhere from $2 to $8 for these.
What is the MERV rating of a furnace filter?
Their filters capture more than 85% of the particles that normally end up in your home’s air. They make furnace filters with MERV ratings of 8, 11, and 13. These ratings will fit most residential needs.
What does MERV mean in furnace?
MERV ratings indicate how effective a filter is at keeping different particles out. You might have been using furnace filters with one that is too low or too high for your furnace without knowing it. If the rating is too low, potentially dangerous or damage-causing particles can easily slip by.
Which is better, pleated or reusable?
Disposable pleated filters are more effective than disposable fiberglass filters, and they’re available in higher MERV ratings (up to 13). Reusable metal filters are more convenient, but much more costly as well.
Where are MERV filters used?
Filters with high MERV ratings are used in specialized locations where particulate matter and contaminants carry bigger risks, like in medical facilities and manufacturing facilities where medications are made.
What is the ASHRAE rating system?
The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) developed this rating system to make it easy to find filters that block out certain types of particles.
What does MERV stand for?
MERV stands for Minimum Efficiency Reporting Value. The rating was devised by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) to answer one question:
What does M mean in MERV?
The ‘M’ in MERV rating stands for ‘Minimum.’ As you can see, the HEPA filters surpass the most restrictive 0.3-1.0 micron particle size interval MERV rating is based upon.
When was the MERV scale first used?
Here is Ron Wilkinson’s (P.E.) commentary on the MERV scale when it first came to light in 1987:
Is MERV rating important?
What is interesting is that you’ll rarely see MERV rating in an air purifier specification sheet. It is quite an important filter-specific factor.
What does a higher MERV rating mean?
A higher rating means that the filter can trap smaller air particles. While you may automatically think that a higher MERV rating means a better air filter, that's not always the case. Higher MERV ratings aren't always necessary and can decrease your unit's efficiency. The best MERV rating will be the one that suits your needs ...
Why is a MERV rating important?
A MERV rating is important because it helps you understand an air filter’s effectiveness so you can choose the right one for your particular needs. For example, if you have someone in your home who suffers from allergies, you may want a higher MERV rating.
What Is MERV Rating on Filters?
If you'd like to know what a MERV rating is, you're in the right place. MERV stands for Minimum Efficiency Reporting Value. In short, a MERV rating lets you know what air particle size an air filter will trap. A higher rating means that the filter can trap smaller air particles.
How many microns does a MERV filter remove?
A filter with a MERV rating of between 1-6 can remove particles anywhere between 0.3 to 10 microns with an effectiveness of 20%. It can remove small particles such as dust mites, spray paint dust, carpet fibers, and pollen.
What is the best MERV rating for a home?
In general, the best MERV rating for a home is somewhere between 8-10. These filters will capture a large portion of the airborne particles and improve indoor air quality without making your energy costs rise significantly.
Why is the MERV rating scale used?
In 1987, the American Society of Heating, Refrigerating, and Air Conditioning Engineers designed the MERV rating scale to give a more accurate picture of an air filter's capabilities. Unlike other scales, which emphasized a need to increase the number of particles passing through an air filter, MERV was designed to offer a balance between particle ...
What is MERV scale?
The MERV scale also helps you balance your air quality and energy efficiency needs. The rating gives you the worst-case possibility for an air filter, so you can get a good idea of how it will perform. You can get by with a lower MERV rating and save money on your energy bill in some cases.
What is a MERV rating?
A MERV rating chart shows a numerical value. The range is from 1 (lowest efficiency) to 20 (highest efficiency). MERV stands for Minimum Efficiency Reporting Value. This is an industry standard rating system. Use this rating system compare filters made by different manufacturers. This rating system reports how well the filter captures and holds dust. The chart below shows the MERV ratings. It shows particle size ranges. It also shows air filter efficiency levels. Efficiency is measured by the percentage of particles captured. In January 2009 ASHRAE stopped recognizing MERV 17 -20 values. These values are shown to reflect the common vernacular used by many players in the filtration industry
What is a MERV 14 filter?
The High Capacity MERV 14 Media filter (HC-14) provides a large volume of dust capacity. This 4 inch filter has over 60 square feet of synthetic dirt grabbing fibers. It is 75% efficient on particles 0.3 -1.0 microns, 85% efficient on particles 1-3 microns and 95% efficient on particle larger than 3 microns. The filter has a Galvanized steel frame, the filter dimensions are 20″ x 19.75″ x 3.75″. The Back pressure from this filter is 0.22 WG.
What is the M value of an air filter?
Filters with a (M) value 5 through 8 remove finer dust particles. These air filters are used to protect people or products from airborne contaminants. These particles could hurt health and productivity.
Is a MERV filter good for a furnace?
They remove the bulk of dust we see in homes and offices. They generally allow enough air to flow through a furnace filter to allow the blower to stay cool.
Is electrostatic air filtration better than media filters?
Electrostatic air filtration is not easily compared to media filters. Its and apples and oranges kind of thing. In some ways they are better than all media filters in others they have drawbacks. The (M) rating is 16 or above and they are washable.
Does Ashrae recognize Merv 17-20?
ASHRAE no longer recognizes MERV 17-20 values. This level of filtration does fall into the MERV system but they are shown here to add continuity to the overall filter picture. These filters remove at least 99.97% of dust particle and are capable of removing viruses and radioactive material.
What does MERV mean?
MERV is an acronym for minimum efficiency reporting value. The MERV rating and testing standard was first designed by the American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) in 1999 and is updated periodically, the last being in 2017. . . The MERV value represents the particle capture efficiency of a filter at specific size ranges.
What is MERV A?
ASHRAE’s testing standards specify an optional testing method for determining filter efficiency without electrostatic charge. The values determined from this test are MERV-A values. An easy way to remember the distinction between MERV and MERV-A is to think of the “A” as standing for “actual,” so a filter’s MERV-A rating represents its “actual” efficiency.
How to calculate MERV of a filter?
To calculate a filter’s MERV value, test dirt with specific sized dirt particles are drawn through a test duct onto a filter. The particles are divided into three broad size ranges known as E1, E2 and E3. How efficient the filter is against all three size ranges is compared against a MERV chart and the final MERV value is the highest value where the filter meets all three requirements of MERV.
What is a MERV 13 filter?
In the last year, the term “MERV-13” has been circulating in the news and on the Internet as a result of several widely recognized organizations, such as The CDC, OSHA and ASHRAE recommending MERV-13 air filters as the minimum filter efficiency. Some local jurisdictions have even required MERV-13 rated air filters to prevent the spread of COVID-19 in public buildings, such as shopping malls, schools, and office buildings.
