Taking Steps for Cleaner Air for Respiratory Virus Prevention

Recommendation

As possible, take steps for cleaner air. This can mean bringing in fresh outside air, purifying indoor air, or gathering outdoors. Virus particles do not build up in the air outdoors as much as they do indoors.

How it works

Some germs spread in the air between people. This happens more easily in indoor, crowded spaces with poor airflow. To reduce the risk of exposure, it helps to improve air quality by increasing airflow, cleaning the air with air purifiers, or opting to gather outdoors.

Steps you can take

• Bring as much fresh air into your home as possible by opening doors and windows and/or using exhaust fans.
• If your home has a central heating, ventilation, and air conditioning system (HVAC, a system with air ducts that go throughout the home) that has a filter, set the fan to the "on" position instead of "auto" when you have visitors and use pleated filters. Change your filter every three months or according to the manufacturer's instructions.
• Use a portable high-efficiency particulate air (HEPA) cleaner.
• As possible, move activities outdoors, where airflow is best.

Steps organizations can take

• Ensure existing HVAC systems are providing at least the minimum outdoor air ventilation requirement in accordance with ventilation design codes. Applicable codes are based on the year of building construction or latest renovation and intended building occupancy.
• Aim for 5 or more air changes per hour (ACH) of clean air. This can be achieved through any combination of central ventilation system, natural ventilation, or additional devices that provide equivalent ACH to your existing ventilation.