![](http://www.airpointer.tech/wp-content/uploads/2019/03/filter47.jpg)
Procedure BU3a - Replacing the sample filter (classic version)
Parts you need: Sample filter 47 mm [800-330030]
Tips:
- Avoid touching the filter, grab it from the edge or with tweezers.
- It will take a few hours until the filter is well-conditioned, this effect can be seen on your ozone measurement.
- Do not over tighten the filter ring