The air we breathe each day defines our well-being as we need it to be clean, healthy, and pollution-free. We need clean air to breathe to prevent allergies and viruses. This is why the air quality outdoors is important.
Indoor air quality also needs to be healthy air to breathe in. The indoor air quality usually depends on the HVAC systems installed in our homes.
The acronym of HVAC stands for heating, ventilation & air conditioning. The global pandemic COVID-19 made us aware of the importance of healthy air in our homes.
HVAC systems ventilate the indoor air and maintain the temperatures. It uses the outdoor and filters it out to provide clean air to breathe. The HVAC system comprises several components.
One important component of the HVAC system is the air filters. HVAC air filters are preventing allergens, viruses, etc., from entering the indoor environment.
Air filters act as a shield from pollens, dirt, dust particles, pollutants, moisture, etc.
Understanding Covid-19 Spread & HVAC Filters to Prevent the Spread of Covid -19
Since Covid 19, scientists are trying to figure out if HVAC filters can prevent the spread of the virus. Covid 19 virus spreads through the respiratory droplets of an infected person.
When these droplets get expelled through sneezing or coughing, the virus spreads. The virus particles remain in the air for a while, making the virus air-borne transmitters. This can infect those inhaling the same air.
In the different rooms of a home, the possibility of Covid 19 spread becomes high. This is why you should maintain the rooms’ air ventilation and install air filters of high MERV value.
HVAC air filters come in two different varieties, fiberglass and pleated air filters. Fiberglass filters are inexpensive filters that capture large particles like lint and dust.
Yet, they don’t capture the small microns and need to be replaced more often from the trapped lint. Pleated air filters capture microorganisms like pollen, pollutants, viruses.
Pleated filters are effective in filtering out most allergens and other microorganisms. Pleated filters have the extra surface area, and due to this, it filters out more dirt and viruses.
The extra pleats have fine holes to trap the microns and other harmful particles.
MERV ratings mean Minimum Efficiency Reporting Values. HVAC filters have MERV ratings based on their ability to capture different particles. The microorganisms are of different sizes, from 0.3 to 10 um microns.
So, high MERV rating filters capture even the smallest particles passing through it.
High MERV ratings also state that the filter is more efficient. Fiberglass filters have a MERV rating between 2 to 4, and the low-end pleated filters have a 6 MERV rating.
The MERV scale goes up to the rating of MERV 20 value, indicating the HEPA filters used in hospitals.
For HVAC systems in your home, an ideal MERV rating of 13 is best & anything above will be overkill. Any MERV value above MERV 13 will add more pressure on the HVAC system, damaging it.
Air Filter Sizes and Dimensions
HVAC filters come in different dimensions. Some of the common sizes of HVAC systems installed in homes are 14x30x1 MERV 13 air filters. Another accepted size is 20x25x4 MERV 13 air filters.
While replacing the old filters, you will need to find the size that will fit well in your HVAC system. The filter dimensions are usually printed on the frame.
While replacing the filters, ensure to get the right filter size to fit your HVAC system.
Recommend MERV Rating for Preventing Spread of Covid 19
Filters have a huge impact on the indoor air, and a high MERV rating filter helps to prevent the spread of Covid 19. ASHRAE (American Society of Heating, Refrigerating and Air Conditioning Engineers) defines the MERV rating standards.
As per the ASHRAE standards, the MERV value of air filters used in homes should be at MERV-13. MERV 13 filters ensure that the air filtration targets the aerosolized virus particles.
Scientific research indicates that the particle size of the SARS-CoV-2 virus is around 0.1 µm. A virus that is as tiny as 0.1 micrometer gets spread into the air through microdroplets.
MERV 13 filters are 85% more efficient in capturing even the very minute viral particles of 1um to 3um. It is thus suggested to use air filters of MERV 13 value to prevent the spread of Covid 19.
Low MERV value filters like MERV 6 & MERV 8 are only 20% effective in capturing the particles of the same range. MERV 13 Filters can capture more allergens & pollen that are unsafe for the health of your family.
Also, MERV 13 air filters are effective in filtering out the contagious Covid 19 aerosols. While installing the air filters, follow the instructions given in the manufacturer’s guide. Well-installed air filters are effective in filtering out the air.
Cleaning and Replacing Air Filters
One of the main characteristics of an air filter is that it gets dirtier as the air gets cleaner. This is why you must clean the HVAC air filters from time to time. Cleaning filters ensures that all the trapped particles get removed from the filter.
According to the manufacturer’s recommendations, change air filters every 3 months. Changing air filters on a timely basis ensures that filters release good quality air.
Clean air keeps your family safe from allergies like asthma and respiratory diseases. If the air filters are not changed, they get clogged with dirt and grim, which makes HVAC systems work harder.
Hence changing the filters is important to improve the efficiency of HVAC systems.
To prevent the spread of Covid 19 in homes, ASHRAE suggests that one cleans and sanitizes the filters. It would be best if you use only certified and approved disinfectants for filters.
Follow protective measures and protocols while cleaning and replacing the HVAC air filters. Also, one should follow preventive protocols like N95 masks, use a face shield, and gloves.
Also, ensure that you wash hands with soap or clean hands alcohol-based sanitizers to keep Covid 19 at bay. When the technician is replacing the old filter, ensure that it is not shaken or dropped.
This prevents the trapped aerosols from circulating and spreading in the air. You should pack the old air filter immediately into a trash bag.
Always make sure to seal and throw the old filter in the outdoor trash to prevent the possible spread of the virus.
To keep your home and family protected from Covid 19, it is always best to follow the WHO guidelines. Follow the best hygiene practices, like washing hands for 20 seconds with soap and water.
Always maintain social distancing and keep your home surfaces clean and sanitized. Ensure to get regular inspection and maintenance of HVAC systems to improve efficacy.
One must clean the air filters to get rid of air particulates and aerosols. Ensure to change air filters on a regular basis as per the advice of the manufacturer. Follow these preventive steps. You and your family will breathe safe and healthy indoor air then.