We tend to spend most of our time in our homes; hence it is important to take notice of the quality of air that we breathe in. Our indoor air quality affects our health as it can be filled with many pollutants, dust, viruses, pollen spores, allergens, and pet dander in case of any pets in the house. All these pollutants can consequently cause respiratory problems and can be a health hazard for allergic people.
Air filters are designed for the sole purpose of capturing these pollutants from the air. But it is vital to judge the effectiveness of any air filter before buying it. this is where MERV comes into play.
In this article, we’ll explore what is MERV rating, and why is it important to consider the MERV rating while looking for an air filter.
What is MERV?
MERV stands for Minimum Efficiency Reporting Value. It is a standardized unit for measuring the effectiveness of an air filter. Through MERV rating, you can evaluate the performance of an air filter in HVAC (Heating, Ventilation, and Air Conditioning) by its ability to capture different size particles.
The MERV Rating scale was developed by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). This scale ranges from 1 to 20, with greater numbers indicating higher efficiency while lower numbers indicating less efficiency in capturing particles from the air.
How is MERV Rating Determined?
MERV rating is determined by exposing the air filter to various-sized particles and measuring its ability to capture those particles. These particles range from 0.3 to 10 microns. The ability of the filter to capture smaller particles like smoke and bacteria is assessed at higher MERV rating values while the filter’s ability to capture large particles like dust and pet dander is evaluated at higher MERV rating values.
Here’s a table for your better understanding:
| MERV Rating | Efficiency (%) | Particle Size Range (Microns) |
| 1 | Less than 20 | > 10.0 |
| 2 | 20 – 34 | 10.0 – 3.0 |
| 3 | 35 – 49 | 3.0 – 1.0 |
| 4 | 50 – 69 | 3.0 – 1.0 |
| 5 | 70 – 84 | 3.0 – 1.0 |
| 6 | 85 – 89 | 3.0 – 1.0 |
| 7 | 90 – 95 | 3.0 – 1.0 |
| 8 | 90 – 95 | 3.0 – 1.0 |
| 9 | 90 – 95 | 3.0 – 1.0 |
| 10 | 90 – 95 | 1.0 – 0.3 |
| 11 | 95 – 98 | 1.0 – 0.3 |
| 12 | 95 – 98 | 1.0 – 0.3 |
| 13 | 95 – 98 | 0.3 – 0.1 |
| 14 | 95 – 99 | 0.3 – 0.1 |
| 15 | 95 – 99 | 0.3 – 0.1 |
| 16 | 95 – 99.9 | 0.3 – 0.1 |
| 17 | 99.97+ | 0.3 – 0.1 |
| 18 | 99.97+ | 0.3 – 0.1 |
| 19 | 99.97+ | 0.3 – 0.1 |
| 20 | 99.97+ | 0.3 – 0.1 |
The efficiency percentage indicates the filter’s ability to capture particles of a specified size range. For instance, an air filter with a MERV rating of 8 can trap around 90 to 95 percent of particles in the size range of 3.0 to 1.0 microns.
Why is MERV Rating Important?
Here are some of the factors that determine the importance of MERV Rating:
Improved Indoor Air Quality: The primary purpose of air filters is to remove airborne particles and pollutants from the air. MERV rating helps you in determining the right air filter for your living space which leads to better removal of the harmful particles from the air consequently improving the indoor air quality.
Health Benefits: One can’t deny the important role that air filters play in maintaining good health. Incapable air filters can result in serious health conditions like asthma, respiratory problems, and triggered allergies. By using a higher MERV rating air filter, you can cut exposure to those particles and microorganisms that can cause these issues hence improving your overall health.
Extended HVAC System Life: Air filters with higher MERV ratings can collect all the particles from the air that can accumulate in your system causing poor performance and eventually causing a system breakdown. Air filters can make your HVAC system more durable leading to potential cost savings.
How can you choose the right MERV-rating air filter?
You have to know the efficiency of each MERV-rated filter to know which one is best for your space.
MERV 1-7
These are the lowest-rated filters. These are basically used in spaces that have great air passages because they capture only large particles. These MERV-rated filters are ideal for industrial use as they capture only large particles saving the machinery from any breakdown.
MERV 8-13
Residential buildings usually use filters of MERV rating ranging from 8 to 13. These filters possess a great ability to capture small particles like dust, pet dander, smoke particles, and other pollutants. These filters can significantly reduce potential health issues like sneezing.
MERV 14-20
These filters are most commonly used in laboratories and hospitals where a clean and sterile environment is essential for the safety of patients and other people around. These filters can capture germs, viruses, and other harmful microorganisms.
HEPA Filter
HEPA filter is a mechanical pleated air filter. It stands for High-efficiency Particulate Air (filter). These filters have a MERV rating of 17 and above and are able to capture 99.7% of the pollutants including dust mites, mold, pollen, and cigarette smoke.
U.S Environmental Protection Agency (EPA) also suggests using this filter in your HVAC system if you have any kind of allergies and if there are children or elderly people in the home.
You now have an understanding of MERV Rating, how it is determined, and what importance it has regarding air filters. This article also discussed how you choose the best air filter for your living space with the help of the MERV Rating scale.
However, it is crucial to know that your air filters require continuous cleaning after every 3 or 4 months. Consulting with HVAC professional for ac maintenance in Dubai can help determine the optimal MERV rating for your specific needs, ensuring a healthier and more comfortable living environment for you and your loved ones.
Leave A Comment