How do I Know When to Change My Carbon Filter?

Carbon filter lifespan is very difficult to predict, as every house has differing levels of background VOCs.

As such, we recommend what we call the “smell test” to know when to replace a carbon filter. To run your smell test:

  1. Open your purifier and remove the carbon filter
  2. Hold the middle of the carbon filter up to your nose (within 1-3cm) and smell the carbon filter
  3. If you smell a sour, acidic or chemical smell, then this means your carbon filter is saturated and should be replaced.

Perform the above 3 steps on a regular basis (every 1-2 weeks) to tell when to replace your carbon filter.

Learn more: why it’s difficult to predict the lifespan of a carbon filter »


Free Guide to Breathing Safe

Want to learn more about breathing clean air? Join thousands more and stay up to date on protecting your health.

Was this article useful?163
Smart Air low cost purifiers

Smart Air is a social enterprise and certified B Corp that offers simple, no-nonsense air purifiers and provides free education to protect people from the harms of air pollution.

Certified B-Corp air purifier company