I have severe asthma. I have tried hiking in an N95 mask and I have asthma attacks the whole time. My home environment is kept extremely clean by my custom high-power low-cost air filtration system; my indoor PM values usually stay at zero. The only other variable is N95.

So what is N95? The certification standards document explains that it filters 95% of airborne particulate matter. I’ve measured PM levels in excess of 800 micrograms per liter of air on a regular basis throughout the current fire season. If you filter out 95% of that, you’re still breathing in a moderate dose of particulate matter. N95 just isn’t enough, especially during exercise.

What Else Works?

There are several levels of filter standards. N is a basic one. P is the highest standard. It does a lot more than I need; filtering out organic acids and gaseous oils. It also jumps from filtering just 95% of particulates to filtering 99.9% of airborn particulate matter. HUGE IMPROVEMENT!

Also, these filter masks are not medical so no doctors are going to miss out to let me breathe easier.

What About Covid?

This filter is more than adequate for filtering out virus particles. Also, it has a safety mesh which covers the filter to prevent skin contact with the dirty filter material. Lastly and most critically, this respirator directs exhalation down rather than forward. This means breathing out is not going to direct your breath at other people, just like all the non-N95 masks simply redirect exhalation sideways or down rather than filtering it.

Ideally, the respirator would be filtering exhalation but I have looked far and wide and talked to industry experts; this kind of reusable respirator just doesn’t exist. Luckily because this one directs exhalation down, it will be just as effective as most other face coverings for protecting other people, should I become unknowingly infected.

The Parts

Here is the respirator! You can see the downward-facing exhalation duct, and the attachments to each side for the replaceable filter cartridges.

Lastly, here are the P100 filter cartridges. Based on the current particulate matter concentrations and the rated capacity of these filters, it looks like one set of filters will probably last you years. I bought an extra set just to be safe.