HackerTube / Video
How to Make a DIY Air Filter | Ask This Old House
This Old House

This Old House's Ross Trethewey explains MERV filter ratings and how air filtration works, then shows how to build a localized DIY air filter, including a box fan with multiple filters.
HN recommends it as a practical breakdown of filtration versus air volume and a clever box-fan filter design.
3 Hacker News mentions · 2021–2022