The Air Journal is OxiClear's magazine on air, breathing and the craft of masks. Issue four.
Two masks, one difference: a small disc that opens when you breathe out. What the valve does, why some doors say no to it, and how to choose in ten seconds.
The gantry over the road says NEW DELHI, ENTRY. On the last morning of 2017 it was barely legible, the station behind it reduced to grey by smog. Every commuter passing under that sign lives with the question our range asks in its very first click: valve or no valve? It looks like a style choice. It is really a question about your day, and it takes ten seconds to answer once you know what the disc is for.
What the disc actually does
An exhalation valve is a one-way door. Breathe in and it stays shut, so the in-breath comes through the filter media like on any rated mask. Breathe out and it opens, and the out-breath leaves by the short route. NIOSH, the American agency that writes the rulebook for workplace respirators, describes valved masks as suited to high work rates and longer periods of wear. That matches the road exactly: the valve helps release exhaled heat and moisture, which is precisely what you want deep into a commute, a ride or a shift outdoors.
So the valved OxiClear is the one we point at moving days: commuting, cycling, outdoor work, longer wear. If your mask time is mostly engine time, the disc earns its place.
Why some doors say no
In a typical valved mask, the valve is a port in the filter media itself. The in-breath gets filtered; the out-breath can leave through the port without meeting the filter at all. That is why pandemic-era CDC guidance told valved-mask wearers to cover the valve wherever filtering the out-breath mattered, and it is why some workplaces, schools, hospitals and airlines still require a non-valved design at the door. When NIOSH actually measured valved respirators, the nuance was kinder than the reputation: even through the valve, they cut outward particle emissions to levels similar to or better than surgical masks and cloth coverings. But institutions write rules for categories, not nuances. Where the setting says no valve, wear the no-valve. That is exactly what ours is for.
OxiClear routes the air its own way. In the current design, exhaled air passes through the installed filter before it reaches the valve. The valve itself works automatically and should not be opened, removed or altered.
The mask is identical twice over. The disc only decides how your out-breath leaves.
How to choose in ten seconds
Moving days, most days: take the valved. A setting with a rule, a workplace, a school, a hospital, an airline: take the no-valve, and note that the kids design is no-valve. Beyond that one fork, you are choosing the same thing twice. Either way it is a premium reusable anti-pollution mask: with a clean filter and a close fit, it helps reduce exposure to airborne particles such as PM2.5, PM10, road dust and smoke particles.
Everything the disc does not change
Same washable cotton body. Same pocket and the same single filter size across the current range, adult and kids, so refills never ask which mask you chose. Same retirement rule for the filter: 21 days or 100 hours of use, whichever comes first, decoded in issue three. Same one-minute fit routine, and fit is still the part that decides what reaches your lungs. And the same proof behind both. OxiClear masks are DRDO Laboratory Tested: up to 99.46% particle filtration efficiency for particles larger than 0.3 microns under test conditions. The full report lives on the Technical page.
Take this with you
- The valve is comfort engineering: an easier out-breath, less heat and moisture. Choose it for commuting, cycling, outdoor work and longer wear.
- Rules beat nuance. Where a workplace, school, hospital or airline requires no valve, wear the no-valve. The kids design is no-valve.
- In the current OxiClear design, exhaled air passes through the installed filter before it reaches the valve. The valve works automatically; never open, remove or alter it.
- Whichever you choose, the filter rule is identical: 21 days or 100 hours of use, whichever comes first.
Put the valved N99 and the no-valve N99 side by side, or start from the whole N99 range. The ratings on the box are decoded in issue one.
Sources: NIOSH, Filtering Facepiece Respirators with an Exhalation Valve: Measurements of Filtration Efficiency to Evaluate Their Potential for Source Control, DHHS Publication 2021-107. Featured photograph: the New Delhi Railway station entry in smog, 31 December 2017, by Sumita Roy Dutta, CC BY-SA 4.0, via Wikimedia Commons, resized for the web.
