},{ "@type": "Answer", When a particle is in the 0.3 to 1 micron in size it is considered microparticle. Once the filter is fully loaded the filter will reach its final pressure drop. MERV Rating Chart: How to Choose the Right Air Filter for You? HEPA is a type of pleated mechanical air filter. Weve also posted one of the popular Pick HVAC FAQ guides on Signs the Filter Needs to be Changed that addresses related topics. As air moves through an HVAC system and encounters a filter, the filter creates resistance to the airflow as it removes particles and contaminants from the air. For example, a 4-inch-thick MERV 12 filter can have a 0.2-inch WC pressure . This value is helpful in comparing the performance of different filters NEC 310.16 Table: Copper And Aluminum Wire Ampacity Chart, NEC 310.12 Table: Wire Sizes For 100-400 Amp Services (83% Rule), kWh To Therms Calculator + Conversion Chart (1 kWh = 0.03412 Therms), MMBTU To Therms Calculator + Chart (1 MMBTU = 10 Therms), Therms To MMBTU Calculator + Chart (1 Therm = 1/10 MMBTU), AWG To Circular Mils Chart (For 4/0 AWG To 20 AWG). This value is helpful in comparing the performance of different filters, The rating is derived from a test method developed by the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) [see. air). When choosing a filter, remember that airflow (pressure drop) is just as important to consider as filtration (MERV rating). Each air filter has its own unique pressure drop. The final pressure drop/final resistance is measured when the filter has reached its total dust holding capacity and is ready to be replaced. However, an important factor is that MERV ratings are not standard and the quality of a filter will vary from one brand to the next, meaning that pressure drop will vary between different filters that are rated the same. It is quite an important filter-specific factor. Minimum Efficiency Reporting Values, or MERVs, report a filter's ability to capture larger particles between 0.3 and 10 microns (m). According to this paper, there's a well established connection between higher concentrations of particles in outdoor air and poor health outcomes, so it would make sense that filtering these particles out of indoor air could lead to better health outcomes. Typical MERV 11 Filter 3M MERV-11 3M MERV-14 How Our Filters Perform Over Time This chart shows how our media performs over time as a 20" x 25" filter collects particulates as measured at different air volumes. 11 filters 11 merv 13 filters 13 merv 8 filters air air filter air filters air flow air purifier air purifiers air quality airborne airborne particles airflow allergens allergies allergy as dust as merv asthma bacteria best air by particle carbon carbon dust clean cleaner cleaning covid dust dust mites dust particles electrostatic filter filter's filtering filters filters air filtration furnace filter hepa hepa filters higher merv higher merv rating home home air homes household humidifier dust indoor air insecticide dust is merv large particles lead dust manufacturer manufacturers manufacturing merv merv filter merv rating merv ratings merv scale merv stands microparticle performance rating mold mold spores more particles my filter particle particle size particles performance rating pharmaceutical manufacturing purifier purifiers rating rating chart ratings refrigerating and air room sanding dust small particles smaller particles smoke technology these filters these particles this filter this rating to air tobacco smoke usa virus viruses water filters what does merv which merv which merv rating. filtration helps provide healthier indoor air quality, Learn more about these recommendations here, recommendations for filtration, humidity set points, automation and more. "name": "Does the material affect the pressure drop of the filter? This system is designed by the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE). Upgrade your filter to a MERV 13 rated air filter to protect your home or business from the spread of viruses and illnesses. This is how they get the name MERV (MINIMUM Efficiency Rating Value). . The minimum efficiency reporting value, is a number from 1 to 16 that is relative to an air filter's efficiency based upon particle size. ($0.05 $0.22/h), How Much Does 1000 Watts Cost Per Hour? (State-By-State Chart), How To Convert Therms To kWh? "text": "As dirt and debris gets trapped by the filter, there is less space for air to pass through, causing the pressure drop to rise throughout the filters life. Average Particle Size Efficiency in Microns, 1.0-3.0 greater than or equal to 20% The Maxum electrostatic is a great air purifier for your home. ASHRAE stands for the American Society of Heating, Refrigerating, and Air-Conditioning Engineers. (std. What are they and why they matter? The rating system is called ASHRAE Standard 52.2-2007. Once the filter is fully loaded the filter will reach its final pressure drop. Just make the filter bigger and you get a lower pressure drop. Hi, great article! Generally, filters with higher MERV ratings have less airflow. The Minimum Efficiency Reporting Value (MERV) rating indicates the effectiveness of an air filter (from 1 to 20) at trapping particles suspended in air. "@type": "Answer", The chart below shows a detailed description for each MERV rating 1 through 16. So, you just purchased some new filters for your home HVAC system. Each filter is assigned a rating based on how much debris a filter manages to block when circulating air. Did you check the MERV rating to see if it is right for your system? However, short of filter neglect, most modern HVAC systems are designed to be able to work with MERV filters in the range of 10 to 13. The (M) rating is 16 or above and they are washable. These filters capture particles at 10.0 microns in size, including pollen, dust mites, and carpet fibers. A .gov website belongs to an official government organization in the United States. M 10 filters are easy on air blowers and fans. Additional annual savings of $2,413 are realized via lower change out costs, reduced solid waste, reduced CO2 emissions AND lower purchase price. "@type": "Answer", The higher the filtering efficiency rating (MERV rating), the higher the pressure drop. This one of the main reasons why it is so important to check, change, and clean your air filter every month to help ensure your air filters pressure drop does not get too high and cause strain on your air conditioner/handler. The majority of residential HVAC systems use a 1" thick filter, but filters are available at 2", 4" and 5" thick. in the Inch-Pound system of measurement. "text": "When you air filter is installed, it is a barrier between your HVAC and your ducts/vents. The MERV scale ranges from 1 to 20, and on the lower end of the scale MERV 1 filtration can capture particles as small as 10 microns with 65% efficiency, and on the higher end of the scale MERV 20 filtrations can capture particles as small as 0.3 microns with 95% efficiency. AFI Replacements (Air Bear, Honeywell, Trane), Poly Anti-Microbial Tackified 1 Inch Media 10oz, Poly Dry / Dry Tackified 2 Inch Media 15oz, Twist-Lock Cylindrical Cartridges for Pneuma Pulse, Flange-Top Cylindrical Cartridge for Farr Tenkay, Conical Cartridge for Donaldson GDX & GDS, Cylindrical Cartridge for Donaldson GDX & GDS, HEPA Crank-Lock Housing 2 Inch Pre-Filter, HEPA Crank-Lock Housing 4 Inch Pre-Filter, 2020 Air Filters, Inc. All rights reserved. At the lower end of the efficiency spectrum a fiberglass or polyester panel filter may have a MERV of 4 or 5. Source: www.doityourself.com. Pressure Drop inches w.c. Here's what you're not being told. E2 arrestance is for the middle size particles. [CDATA[ When your HVAC system is running the filter slows and limits the air that is being pulled through your vents and ducts. They are washable. MERV Rating Chart Understanding MERV Ratings All filters have a MERV rating that falls between 1 and 16. Will it burn up your HVAC system? Leadership in Energy and Environmental Design (LEED) also recommends a minimum of MERV 8. A MERV 13 pleated air filter, the highest quality offering from Second Nature and most other filter companies, has a pressure drop of around 0.25. We cannot assume that the two AHUs operate at the same airflows, so the costs normalized for airflow are best used to make an estimate of annual energy savings by using 5-Star air filters. 3.0-10.0 greater than or equal to 95%, 0.30-1.0 greater than or equal to 95% Always refer to your HVAC systems manufacturers guide prior to changing your air filter. The MERV is a single number that is used, along with the air velocity at which the test was performed, MERV stands for Minimum Efficiency Reporting Value. The most prevalent MERV ratings are MERV 4, 6, 8, 10, 12, 14, and 16: A Higher MERV rating automatically means a better filter. They are available for the home and business. This often coincides with a higher MERV rating; however, this also means that the filter is slightly more restrictive and the airflow rate through the filter is lower. The amount of E1, E2 and E3 dust particles that are captured and missed is calculated. These filters remove at least 99.97% of dust particle and are capable of removing viruses and radioactive material. Bryan. The following example illustrates how this can play out for a hospital investing in higher quality filters to reduce their energy and filter replacement costs. February 2022. Heres the definition of what that actually means: Definition: HEPA filter is a mechanical filter that must remove 99.97% (according to U.S. DOE) of particles whose average size is equal to 0.3 microns. Browse a full list of industry terms to better choose your filters. Includes a moisture resistant, high wet-strength beverage board frame. The MERV rating is a measure of the ability of an air filter to remove particles from the air. Their cost is often moderate and are within many budgets. This rating system reports how well the filter captures and holds dust. All air cleaners require periodic cleaning and filter replacement to function properly. Need more details? As a filter traps and gathers airborne contaminants the filters pressure drop increases and air flow decreases. 2. HEPA and ULPA filters are represented in the 17 through 20 ratings. The filters initial pressure drop (initial resistance) will vary by the filter type, MERV rating, and size. commentary on the MERV scale when it first came to light in 1987: (MERV rating) represents a quantum leap in the precision and accuracy of air purifiers. 14 Culprits To Check For Now, MMBTU To MMSCFD Calculator For Natural Gas + Chart, 8 Best Infrared Heaters For Indoors, Patios, Garages (With ECO Thermostats), AGM Battery Voltage Charts: 12V, 24V Deep Cycle Battery Voltage, Lead-Acid Battery Voltage Chart For 6V, 12V, 24V, 48V Batteries, Natural Gas MMSCFD To MMBTU/Day Calculator + Chart, Smoke, dust, oil smell, bacteria, sneeze droplets, Car emissions, bigger dust particles (lead), Legionella, Hair spray, mold spored, mite debris, fabric protector, cat, and dog dander, Pollen, sanding dust, cockroach debris, textile fibers, 85% for 3.0-10.0 m particles, or greater, 90% for 3.0-10.0 m particles, or greater. Their rating is based upon filtering out a particular size of air particles, 0.3-micron ones. These air filters are great for people with pets. HEPA stands for High-Efficiency Particular Air. It is measured in Pascals in the SI system. They generally allow enough air to flow through a furnace filter to allow the blower to stay cool. Pleats look like an accordion, and can more than double the face area of a filter. In fact, they are high-efficiency filters. The process is repeated 6 times. To build some good comparative data we tested 20 different air filters of various types, thicknesses and efficiencies. Besides the basic need for good indoor air quality (IAQ), many extremely relevant reasons exist in 2020 to discuss air filters, according to Kathleen Owen, Fellow ASHRAE, member of the ASHRAE Epidemic Task Force, and Carolyn (Gemma) Kerr, Ph.D., Life Member ASHRAE. } It also shows air filter efficiency levels. Weigh the test filter. Most manufacturers recommend ratings of 0.5 or lower for the IWC test. "@type": "Question", The majority of residential HVAC systems use a 1 thick filter, but filters are available at 2, 4 and 5 thick. They begin at MERV 1 and go as high as MERV 20, with filters rated MERV 16 through 20 being mainly used in hospitals, research laboratories, computer labs, etc. In case you havent heard of MERV before, it stands for Minimum Efficiency Reporting Value. "acceptedAnswer": { // ]]>. 1.0-3.0 greater than or equal to 95% Official websites use .gov "name": "What initial pressure drop vs. final pressure drop? { The "dirt" on the filters adds resistance. In 2020, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recommended switching from MERV 8 filters to MERV 13+ filters in order to help protect against the COVID-19 virus. In addition, poorly designed and installed duct systems already have external static pressures that are too high. We will help you understand your best air filtration options. The dirty MERV-8 filters had lower pressure drops than the clean MERV-13s. When youre buying an air purifier for a specific purpose, you need to know how big the air contaminants youre looking to remove are. This depends on a variety of factors, including the type of air filters you have, the size of your home, the number of people in your household, the presence of pets, and your own personal preferences. "name": "Does air filter pressure drop change? A filters pressure drop directly corresponds to a filters air flow rate. Thickness of the filter. An air filters minimum efficiency reporting value (MERV) rating measures how effectively the filter stops dust and other contaminants from passing through the filter and into the air stream. MERV ratings are derived from the ASHRAE 52.2-2012 test which groups the particles sizes into three categories. For comparison, a grain of sand is about 60 microns. "@context": "https://schema.org", Tankless Water Heater Breaker Size Calculator: What Size Breaker? Contaminant Size Intervals. It's a nationally controlled and governed rating system established by ASHRAE and is the most widely used ratings for most US-based filter brands. Use this rating system compare filters made by different manufacturers. ", A 1 MERV 13 pleated filter has a pressure drop of around 0.27, and a 1 MERV 8 has a pressure drop of around 0.14. A filters pressure drop is measured twice, once when the filter is brand new and again when the filter has been in service and is loaded with trapped air pollutants. The higher the MERV of a filter, the smaller and the more particles it will remove from the air that passes through it. MERV 30 filters dont really exist, the MERV rating gets only up to 20. Your HVAC equipment will give off a few clues that the filter is too restrictive and creating unacceptable pressure drop. "@type": "Question", How to Tell if I Should Change Furnace Filter. Pressure drop directly corresponds to a filters air flow rate." The most prevalent MERV ratings are MERV 4, 6, 8, 10, 12, 14, and 16: MERV Rating In Air Purifier Specification Sheets (Or Lack There Of) A Higher MERV rating automatically means a better filter. Typically, the higher the MERV rating, the higher the pressure drop and the more restrictive the air flow is. Minimum Efficiency Reporting Values, or MERVs, report a filter's ability to capture larger particles between 0.3 and 10 microns (m). They usually have the lowest MERV of all filters as well. Also, just because a filter fits with a system, that doesn't mean it's the best filter for the system. A MERV 8 filter can remove particles down to 3 microns in size at an efficiency of 70 percent or greater (1 micron is about 0.04 thousandths of an inch). Doing so could cause strain on your HVAC unit and could cause costly maintenance and repairs. The difference between the FPR and MERV ratings is that FPR uses a scale of 1-10, while MERV uses a scale of 1-16. THE PRODUCTS YOU NEED, Commercial Buildings. "name": "Do higher MERV rated filters restrict air flow? Q: Can HVAC operations strategies help prevent the spread of COVID-19? Firstly, MERV ratings range between a 1 and 20 scale, which denotes the effectiveness and efficiency of filters to catch specific air-particle sizes. } "text": "A filters pressure drop directly corresponds to a filters air flow rate. As the MERV rating increases the media typically becomes loftier and thicker, to capture more air pollutants, with this you could see slightly more air restriction. This is an industry standard rating system. Tankless Water Heater Wire Size Calculator: What Gauge Wire (AWG)? According to the standard's application guidelines, particles in this size range include pollen, dust mites, mold spores, hair spray, powdered milk, and of course, snuff. Even filters sharing the same MERV rating may have differing pressure drops. During each cycle a predetermined amount of dust particles is released into the airstream. MERV17 through MERV20 filters are typically used in surgical operating rooms, clean rooms and other contexts that require absolute cleanliness. Before we look at the MERV rating chart (1-20 rating for 0.3 10 micron particles), lets answer this question: Do you know why HEPA filters are called HEPA? The rating was devised by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) to answer one question: Which air purifier is the most effective? The test results are then used to give a filter its MERV rating. air), Latent Heat (BTU/hr) = 0.69 x CFM x gr. That's all. Our Media Air purifiers use MERV 11 filters. This is usually when the filter is new. Woodhead Publishing, 2017. 3.0-10.0 greater than or equal to 95%. Air filters can be used as final filters or pre-filters. This results in lower air pressure on the side of the filter from which the air exits. 3.0-10.0 greater than or equal to 70%, 1.0-3.0 greater than or equal to 50% Our price is lower than the manufacturer's "minimum advertised price." Rather, they use simplified words that everybody knows. Simple use of MERV rating chart for air purifier filters: The higher the MERV rating, the better the filter. Air Purifiers, Dehumidifiers and Treatment. The higher the MERV, the more efficient the air filter is at removing particles. It's quite interesting that the MERV rating itself is a metric used as a factor in the FPR rating. This is important to consider when choosing a filter for your application and your HVAC unit. We do not recommend M 12 or higher 13 filters. There are a number of factors that determine what the resistance to airflow of a new, clean filter (Initial Resistance, or IR) and the resulting pressure drop will be: 1. Check your filter at least once a month for dust buildup. This MERV rating chart has the MERV ratings, 1-16 on the left hand column and then there are five other columns showing the average efficiency in microns, average arrestance and the final resistance as measured in inches of water. "acceptedAnswer": { The higher the pressure drop the more restrictive the filter is to air flow. That will result in more resistance to air passing through it. VOCs and odors are not covered by ASHRAE tests. However, one study found that actual pressure drops in home. The pressure drop across an air filter will determine how negatively the filter affects airflow. How do I know if I need a higher MERV rating? Standard 52.2 establishes a testing protocol. The scale rates how well a filter removes fine particulates from the incoming air. Does the airflow significantly improve? OK ! SEER = (1 EER100% + 42 EER75% + 45 EER50% + 12 EER25%)/100, Total Heat (BTU/hr.) "name": "What is the relationship between filter pressure drop and air flow rate? 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 is not recommended to continue to use your filter beyond its final pressure drop point. Depending on what size of particles the air filters can trap or let through, they are classified in a chart known as the MERV rating. As the MERV rating increases the media typically becomes loftier and thicker, to capture more air pollutants, with this you could see slightly more air restriction." "@type": "Answer", Other Signs your MERV is Too High / Your Filter Too Restrictive, Can I Temporarily Run My Furnace Without a Filter, Relationship Between Pressure Drop and MERV Rating, Do Not Use High MERV (12+) Filter for HVAC. A MERV rating chart shows a numerical value. LakeAir replacement filters use 4 different MERV rated filters. The accepted pressure drop is different for each air conditioning or air handling system, and you should always refer to your manufacturers guide prior to inserting replacing your air filter to ensure you are using the appropriate filter. A M rating of 13 through 16 are higher quality filters. This could be because your system is moving too much or not enough air through its ductwork. These values were correct at the time of printing and Filtermakers do not accept any liability for any information provided herein. PickHVAC is also a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. You can see from the MERV scale above that MERV 10 filter will filter out 85% of 3.0-10.0 m particles. ASHRAEdeveloped the MERV air filter efficiency rating system. The test is made of six cycles. Spun fiberglass almost always has a lower IR than other materials. This could be because your system is moving too much or not enough air through its ductwork." 99.97% or better for all particle sizes). "acceptedAnswer": { While these numbers are fairly close, at least in this example the filter with a MERV of 11, which is more than twice the MERV 5, had a lower resistance to air flow. "name": "What is static pressure? 6-Pack 24x24x4 XTREME PLUS Air Filters MERV 8 XPH-STD4-405- 24X24X4 - $45 (Pacolet) 24x24x4 Air Filter for HVAC. Use this rating system compare filters made by different manufacturers. It holds 24X24 filters with a depth of up to 20. Welding fumes and milled flour are this size. We are here to make sure you select the right solution for your needs. ". A filters pressure drop changes throughout its use. You must have JavaScript enabled in your browser to utilize the functionality of this website. These filters are used primarily to protect equipment. 1.0-3.0 greater than or equal to 80% MERV ratings 1 to 4 are generally only used as pre-filters but can be found in many typical applications like commercial buildings, furnaces, and window AC units. With finer filtration, fewer airborne contaminates & dust particles are allowed to pass through the filter. What guidelines are available to compare air cleaners? The test is based on particle size. Why? Inexpensive and energy-efficient. Particles that are larger or smaller are trapped with even higher efficiency. Our Complete Recommended MERV Rating Guide is a good source for understanding the best filter for your HVAC system. Typically, the higher the MERV rating, the higher the pressure drop and the more restrictive the air flow is. Because they go off the MERV chart, they are referred to as HEPA filters or high-efficiency filters. Products and solutions to help your business move forward. } The higher the MERV rating, the more efficient the air filter is at removing particles. A MERV rating chart shows a numerical value. Filters down to 10.0 micron particle size, Filters down to 3.010.0 micron particle size, Filters down to 1.03.0 micron particle size, Filters down to 0.31.0 micron particle size, Filters down to less than 0.30 micron particle size.