Fresh Versus Clean Air
Working from home? Learn how to improve your indoor air quality with this clean air strategy.
The weather is getting better and you’re stuck inside working from home. Now that spring is in full bloom, you’re ready to open the windows and let in some “FRESH” air!
But before you do, we need to talk about something important: Outside Air (let’s abbreviate it to “OA”).
Rethinking "Fresh" Air
Think of walking into a room or house that's been closed for a long time; what’s it like? It smells old and musty, right? We need to “air out” the place. So, we opened the doors and windows to introduce OA, eliminate those musty odors, and make the place smell fresher. Yeah, OA does that. OA may be FRESH, but it’s not clean. OA from open doors or windows can help improve Indoor Air Quality, but let’s be clear: OA is not clean.
Outside Air vs. Clean Air
Let's get one thing straight: Outside Air isn't always Clean. It may or may not be cleaner than the air in our homes. It's time to rethink what we mean by "fresh air.” While we often refer to it as "fresh" because it seems cleaner than the indoor air we're used to, it's essential to understand that freshness doesn't equal cleanliness.
A math person would think of it like this:
Outside Air ≠ Clean Air ≠ Fresh Air
Why Does This Matter?
40–60% of indoor pollutants originate outdoors. OA can be dirty, whether filled with particulate matter from diesel engines, burning coal, ocean sand (or even salt), forest fires, or desert dust.

OA contains a variety of odors and pollutants, including aerosols, vapors, and gases, which can impact the quality of the air we breathe.
Our Clean Air Strategy
To truly improve indoor air quality, we need to address both OA coming in and the air already inside, known as indoor air or IA.
This is our Clean Air Strategy: Let’s clean our Indoor Air
and clean the Outside Air allowed inside.
As you welcome the arrival of better weather and think about opening windows, remember: Outside Air might feel fresh, but it's not necessarily clean. We need to prioritize indoor and outdoor air quality to breathe the cleanest air possible. In future blog posts, we’ll discuss how to accomplish our clean air strategy with best practices for ventilation, air filtration, and air circulation.