Interactive Home Ventilation Tool

Interactive Home Ventilation Tool
Updated Feb. 9, 2022

Small particles that people breathe out can contain virus particles, including the virus that causes COVID-19.  If a guest visits your home, improving ventilation (air flow) can help prevent virus particles from accumulating in the air. Good ventilation, along with other preventive actions, like staying 6 feet apart and correctly wearing masks, can help prevent you from getting and spreading COVID-19.

We need your feedback! Help us improve this tool by taking a quick survey after using the tool below.

How can I decrease the level of virus particles during and after a guest visits my home?

Select the options below to see how particle levels change as you adjust ventilation settings.

(To create additional scenarios, including to adjust the length of the visit and size of the home, see the expanded model from the National Institute of Standards and Technology.)

The risk of getting COVID-19 varies according to individual susceptibility and the number of virus particles to which a person is exposed. The fewer virus particles in the air, the better.

Portable air filter
Image of a room
Image of a closed window
Image of an open window
Greater than 99 percent particle reduction
90% particle reduction
80 percent particle reduction
70 percent particle reduction
60 percent particle reduction
50% particle reduction
40 percent particle reduction
30 percent particle reduction
20 percent particle reduction
10% particle reduction
0 percent particle reduction
Greater than 99 percent particle reduction
90 percent particle reduction
80 percent particle reduction
70 percent particle reduction
60 percent particle reduction
50 percent particle reduction
40 percent particle reduction
30 percent particle reduction
20 percent particle reduction
10 percent particle reduction
0 percent particle reduction
HVAC auto
HVAC on/constant