What is “Breathing Zone”

Curious C: What is “Breathing zone”?

Designer: This is Breathing Zone. It is the region within an occupied space between planes 3 and 72 inches above the floor and more than two feet from the wall or fixed air conditioning equipment.

Curious C: Where does this definition come from? I thought breathing zone is the area close to worker’s mouth and nose.

Designer: This definition is based on ASHRAE standard 62.1–2019. But you are right, conventionally, people do refer those area close to your mouth and nose as “breathing zone.”

By the way, ASHRAE 62.1–2019 is “Ventilation for Acceptable Indoor Air Quality”. If your place is a residential dwelling unit, then ASHRAE 62.2–2019 (aka “Ventilation and Acceptable Indoor Air Quality in Residential Building”) is a better standard to look up.