Below is a brief compilation of information available at the EPA website (https://www.epa.gov/coronavirus/indoor-air-homes-and-coronavirus-covid-19#hvac ) which we have copied below with some practical steps

Increase Ventilation with Outside Air

To increase ventilation in your home, you can:

• Open the windows, or screened doors. Do not open windows and doors if doing so poses a safety or health risk to children or other family members (e.g., risk of falling or triggering asthma symptoms).
• Operate a window air conditioner that has an outdoor air intake or vent, with the vent open (some window air conditioners do not have outside air intakes).
• Open the outside air intake of the HVAC system, if yours has one (this is not common). Consult your HVAC manual or an HVAC professional for details +
• Operate a bathroom fan when the bathroom is in use and continuously, if possible.
• Operate the Heat Recovery Ventilator (HVR) or Energy Recovery Ventilator (ERV) if your home has one.++

+ Most homes in southern California do not have outside air installed routinely. This can be added to many existing systems and can be included in a new system using the Lennox Ventilation Control system. The use of an outside air inlet dilutes the air in your home and will slightly pressurize it (pushing air out of the house) when the system is in operation.

++ HRV (Heat Recovery Ventilator) and ERVs (Energy Recovery Ventilators) are not common in Southern California due to our mild weather. The HRV is primarily used in our area as humidity is not an issue most of the year. These devices allow you to ventilate your home and not lose or gain heat from the outdoor air.

Improving natural ventilation

Even with an open window or door, natural ventilation can be limited if inside and outside temperatures are similar and there is little wind.

Use your HVAC system and consider upgrading filters

Since running your HVAC system filters the air as it is circulated, it can help reduce airborne contaminants, including viruses, indoors. By itself, running your HVAC system is not enough to protect yourself and your family from the virus that causes COVID-19 +++. When used along with other best practices recommended by CDC, operating the HVAC system can be part of a plan to protect yourself and your family.

If you have an HVAC system:

• Run the system fan for longer times, or continuously, as HVAC systems filter the air only when the fan is running. Many systems can be set to run the fan even when no heating or cooling is taking place. *
• Check to be sure the filter is correctly in place and consider upgrading the filter to a higher efficiency filter or the highest-rated filter that your system fan and filter slot can accommodate. Consult your HVAC manual or an HVAC professional for details.**
• Open the outside air intake, if your system has one (this is not common for home systems). Consult your HVAC manual or an HVAC professional for details.
• If your HVAC system has an energy-efficient air-to-air heat exchanger, heat recovery ventilator (HRV) or energy-recovery ventilator (ERV) use it, as they increase ventilation.

+++ The addition of a germicidal UVC light (similar to sunlight radiation) has been used to destroy airborne and surface-bound microbes, including chickenpox, measles, mumps, tuberculosis, and cold viruses. ASHRAE (American Society of Refrigeration and Air Conditioning Engineers) has recognized that the UV-C wavelength inactivates virtually all micro organisms living on HVACR surfaces, with kill ratio of up to 99%, depending on the intensity and the light of exposure.

Germicidal irradiators can be easily installed in most system in most central HVAC systems in Southern California in both residential and commercial equipment.

* All of the advanced thermostats from Lennox have the ability to program the fan on you system to get thermostat out of the air filters and to expose as much air as possible to the germicidal irradiator (if so equipped.) The new Lennox variable speed furnaces and air handlers will circulate the air at a very low speed to maximize the effect of these products while providing draft free system operation.