Unhappy couple suffering from bad smell and covering their noses near air conditioner indoors, low angle view
When you’re shopping for an air purifier, you may be wondering: can I get rid of nasty odors with one of these appliances? The honest answer is: air purifiers can significantly reduce odors, along with other gases that our sense of smell might not pick up on. Whether a purifier can fully eliminate an odor, though, depends on several variables — including the concentration of the odor, the rate at which new odor-causing air is entering the space, your unit’s airflow, and how many air changes per hour (ACH) it can achieve. For strong or persistent odors, you may want to do 10+ air changes per hour, depending on the size of the space.
Air purifiers with carbon filtration do the trick by adsorption — a process where molecules or ions from a gas or liquid stick onto a solid surface, forming a thin layer without getting “inside” the target material. Not all smells are the same, either: as you’ve probably noticed cutting into an onion versus an apple, some odors are simply more potent and harder to remove than others. This article covers the science behind how air purifiers filter strong scents from the air, along with the best strategies for using a purifier to reduce unwanted or harmful odors.
How Carbon Filtration Reduces Odors
The key to capturing odor-causing gases is when you use activated carbon (also known as activated charcoal) inside an air purifier unit. Carbon has an enormous internal surface area full of microscopic pores, which trap gas molecules as air passes through — pulling odor-causing compounds out of circulation rather than just masking them.
Because odors are gaseous rather than solid particles, a HEPA filter alone won’t touch them — HEPA is built to capture particulate matter, not gases. That’s why purifiers marketed for strong odors (smoke, pets, cooking, VOCs) typically pair a HEPA filter with a substantial carbon filter.
Tips for Getting the Most Odor Reduction From Your Purifier
Choose a unit with enough carbon. The heavier the carbon bed (measured in pounds), the more odor-causing gas it can adsorb before becoming saturated and needing replacement.
Position it near the source. Placing the purifier close to where the odor originates lets the unit capture gases as they’re released, before they spread and get absorbed into furniture, carpet, and walls nearby.
Manage dwell time. Dwell time is how long air spends inside the purifier as it passes through the filter — more dwell time means more contact with the carbon surface, which improves adsorption. Running a unit on a slower speed increases dwell time and can improve odor capture, but this only works if the air circulating through the unit stays ahead of new contaminants entering the room.
Start high, then settle in. A good general strategy: run the purifier on high speed for the first few hours (or while the odor source is actively releasing gas — for example, while cooking), then shift to a lower or medium setting for ongoing maintenance.
Some odors take longer than others. Odors that have deeply soaked into fabric, furniture, or building materials over a long period of time will take longer to reduce than fresh, surface-level smells — continuous operation over days or weeks makes a bigger difference than a single session.
The Bottom Line
If you’re dealing with a lingering odor problem, a quality air purifier with a substantial carbon filter is one of the most effective tools available for reducing it. Just keep in mind that how much odor gets reduced — and how quickly — depends on the strength and source of the smell, your unit’s carbon capacity and airflow, and how many air changes per hour it can deliver in your space. If these tips don’t quite solve your odor problem, or you’re not sure which air purifier best fits your space and situation, US Air Purifiers is happy to help you find the right match.
USAirPurifiers is a family and veteran-owned U.S. business offering a wide range of high-quality air purifiers, scrubbers, filters, air monitors and humidifiers. The Lulay Team knows that clean air isn’t one-size-fits-all, so we match the right solution to your needs and budget. Invest in your family’s health and breathe easier. Your health is truly our top priority because everyone deserves to enjoy clean air everywhere!