How to Step Up your HVAC for Covid-19
There is real concern over air transmission of the Covid-19 virus and indoor air quality (IAQ) because varying sources indicate that due to a cough, the COVID-19 virus can travel six to eighteen feet in the air and stay airborne from fourteen minutes to three days. And for good reason, our IAQ practitioners over the past three decades have observed that building ventilation systems in offices, schools, and other spaces are often in a neglected state of repair. When the energy crunch hit years ago, many heating, ventilation, and air conditioning systems (HVAC) were designed and operated in a way to save energy and costs of operation. Most HVAC systems are controlled with thermometers and provide air flow and air filtration when the temperature is calling for heating or cooling of the building space. Bringing in fresh outside air and conditioning it with heating and/or cooling is costly and often minimized.
Contact RPF Environmental, Inc. today by filling out an online contact form, or by dialing 603-942-5432.
The American Society of Heating, Refrigeration, Air Conditioning Engineers (ASHRAE) publishes recommendations and standards to assist the public in the design, operation, maintenance, and inspection of HVAC systems as well as education and certification of folks responsible for HVAC systems in buildings. ASHRAE recently published guidance for reopening schools and universities which can also be applied to other office and public buildings. Most are just good hygiene practices that are not always implemented, and HVAC maintenance is often ignored. People would not want to breath the air coming from unit ventilators or HVAC units if they took the time to inspect them and see the dust, debris, and contamination within the units.
The following are key takeaways from the ASHRAE guidance document to consider.
- Maximize the amount of fresh outside air (FOA) being introduced into the area and open windows when practical. Depending on the HVAC system, the weather may be a factor.
- Set the HVAC to change air 6 times an hour with a minimum of 15 cubic feet per minute (cfm) of FOA per person. Keep in mind that the more FOA, the more dilution of Covid-19 in the air is likely to occur.
- When space will be occupied, run the HVAC system continuously rather than only when the thermostat calls for it.
- Consider doing a two-hour pre-occupancy flush in the mornings.
- Every quarter check the HVAC and its filters. Inspect air handlers for damage and clean them thoroughly. Ensure the filters are seated properly.
- Ensure relative humidity stays between 40-60%.
- If the HVAC system will allow it, consider upgrading filtration to a MERV 13 or higher. Investigate pressure drops since they may not allow the system to operate properly.
- Portable HEPA UV-C filter units are a possibility for room sized areas. These will help clean the air if properly maintained.
- School nurse rooms should be treated as isolation rooms with the air exhausted to the outside rather than recirculated by the HVAC and kept under negative pressure compared to the hallway.
- At the entrance of critical areas, consider using disinfection or sticky mats.
Over time the need and effectiveness of the above guidance will be learned. As always, you should stay abreast of the latest industry standards and guidelines required for your facility.
RPF Environmental has been providing air quality testing, including assessments to help measure the amount of fresh air in building spaces, for 30 years. RPF Environmental also offers swab and air sampling to test for the presence of Covid-19, as well as post-cleaning verification and ATP surface testing.
Contact RPF Environmental, Inc. today by filling out an online contact form, or by dialing 603-942-5432.
