Confused by conflicting information about Covid-19? Looking for simple, practical solutions for improving the health of your building? I’ve read a lot on best practices for opening and operating buildings during the Covid-19 pandemic. There’s a lot of advice out there with a lot of questionable suggestions which seem more about making sales than giving sound advice. I finally found an article that I felt confident in sharing. If you want to read the whole beast of an article which includes 5 plus pages of excruciatingly small print (I’ve reached bifocal age where small print challenges me), you are welcome to review, in detail, the science that supports the recommendations. For you, I will provide the link. For those who hate small print and are cool with a summary of the advice, see below:
Increase air flow and exhaust ventilation
There’s a whole bunch of ways to do this and it depends on the type of system you have, which option(s) are available and best for your building, so my advice is reach out to your HVAC contractor and get advice on how best to do this for your system.
If you don’t have a trusted HVAC contractor you can ask, call me. If I can’t figure out how to help you over the phone, we can discuss a free consultation to get you the info you need.
Bring more fresh air in:
- Increase the minimum position of the economizer (the amount it’s always open), so you get constant increase in fresh air.
- Lower the CO2 setpoint if you have Demand Control Ventilation to open the outside air damper more frequently, letting in more fresh air.
- Open a window. If you’re old school and don’t have fresh air options within your HVAC system, open a window.
If you don’t have fresh air options, don’t stress. All airflow is good airflow.:
- Leave fan on all the time. Or if have the ability to program it, adjust occupied schedule to start the fan before entering the building, and continue to run it after folks have left the building. Even if you’re not bringing in fresh air, all recycled air goes through a filter, reducing the amount of Covid-19 junk floating around.
Air Filtration
Follow your manufacturer recommended procedures for installing, sizing and changing air filters. Use extra caution when changing air filters, such as wearing a mask and gloves, and putting the filter directly into a plastic trash bag (don’t carry dirty filters through your facility to dispose of them!)
The CDC has said that MERV13 or higher filters are the correct size to filter the Covid-19 molecule with 90% plus efficiency. This has created a huge push to replace ALL filters with a MERV13 or higher rating, but here’s the rub:
- Most comfort cooling units are NOT designed for MERV13 filters. MERV13 filters are typically made for HVAC units in specialized medical facilities or clean rooms. A typical office building HVAC unit is designed for MERV8 or lower. MERV8 is your typical pleated filter. A fiberglass filter is typically rated MERV4 or lower. Putting a MERV13 filter in a unit designed for MERV8 or lower, will reduce the air flow in the unit, lower ventilation rates and can even cause unit damage over time. Lowering ventilation is a no-no. In addition to worsening your ventilation and overall HVAC performance, you could also be slowly (or not so slowly) killing your compressor.
- Filters are hard to get and typically have long lead times, especially if they are not standard sizes. If your units are rated for MERV13 or higher – go for it! But be aware that you could be in for a long wait and higher than ever costs.
Air Purification Devices
Other alternatives for air purification exist. Solutions that neither restrict airflow, nor reduce ventilation, but do kill Covid-19. Nearly every equipment manufacturer has come out with a version of air purification unit, either in-unit or stand-alone or both. Options abound. To determine which option is best for your HVAC units, I recommend contacting your HVAC professional. If you don’t have one, I can appoint one to you.
Call Advance Air today at 508-763-3738 for more information on how to keep you and your building healthy!