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Download: User Manual

OSR-M1 Assembly Instructions


 Download: Assembly Instructions


Inspect your mask for wear or damage every time you put it on. Take special care to check the straps for tears. Replacement parts will become available in January 2021.

Adjusting of the straps and face-piece position will be necessary to achieve a comfortable fit and maintain a tight seal against your skin. Sometimes it takes a few minutes of wearing the mask for the fit to really seal well. 

  • The straps should be just tight enough to get a seal, and not more than that to improve comfort.
  • Adjusting the position the top strap sits on your head will adjust the fit, particularly around your nose.
  • The lower straps may be tightened or worn loosely based on personal comfort, and as needed to help hold the face-piece in place.Turn your head (side to side, up, down) to check stability.
  • Try raising or lowering the position at which the Facepiece sits on your nose, and depth to which your chin rests inside.
  • Adjust chin placement; you may prefer the inner Facepiece to rest fully against your chin or more on the surface
  • Throughout the day you may adjust the seating position of the mask on your face, and the straps on your head to find what is comfortable and maintains a seal.
  • Once properly fitted, no air should be able to escape around the edges of the Facepiece. If your glasses are fogging, with any mask, it means it is not fully sealed and not entirely effective at blocking particles.

Notes about extended use:

  • The inside of the mask will get wet with exhaled humidity. Cold weather will increase the amount of condensation. Clean hands and clean wipes can be used to dry out the inside of the Facepiece periodically.
  • After extended periods of wear the bridge of your nose may become sore. This seems to go away after multiple uses. It can also be accommodated by shifting the seating position of the mask on the face.


The OSR-M1a can easily be washed by hand or in a dishwasher:
  1. Completely disassemble your mask, and remove the filter.
  2. Do not attempt to clean the filter it will lose its effectiveness.
  3. Gently scrub pieces by hand in hot, soapy water. Or, to use a dishwasher: place the straps in a utensil bin, and the remaining components on top rack of the dishwasher and run through normal cycle. Be sure the straps are not able to fall into the turny bits of the dishwasher. 
  4. Dry thoroughly on a rack or with clean cloth before reassembly and use. A quick shake in the air before setting to dry, can speed up the process. Store protected in a clean, dry, breathable place when not in use.


Isopropyl alcohol (rubbing alcohol) >70% can be used to wipe down the mask components to further decontaminate the surfaces. Periodically wipe down any high-touch surfaces such as the outside of the filter grill and the inside of the facepiece. Do not wet the Filter Media.

Filter disinfection can be as simple as following the Wait & Reuse method described in the next section. Data shows there is a substantial decay of virus after 7 days. For the occasional wearer the mask can be left to dry out in a breathable location. We recommend either hanging it by the straps, or setting it Facepiece down to allow moisture to drip away from the filter.


The lifetime of your filter depends on how frequently you wear the mask and what you are exposed to. 

  1. If you are a front-facing worker who wears the mask for multi-hour shifts you may expect to replace the filters more regularly. You may replace the filter daily, or to conserve Filter Media, use the Wait & Reuse practice (more below).
  2. If you are not a front-facing worker and are instead an occasional wearer only using the mask to go to the store or on a flight, then leaving the mask hanging to dry until your next use is likely adequate. We recommend a fresh filter at least once a month.


  1. We recommend changing the filter if any noticeable change in breathing resistance, discoloration, or smell occurs. If any biological material has soiled the mask or filter the filter should be discarded and the mask fully cleaned and disinfected.
  2. Before inserting a filter into the mask check for any rips, tears, or mechanical failures. If any failures are found discard and replace the filter immediately.
  3. The filter should be allowed to fully dry between every use.
  4. When wearing the mask the condensation from your breath will build up inside the mask. After hours of use you may wish to dry/wipe-out the condensation inside the Facepiece.
  5. A filter decontamination practice is to Wait & Reuse: replace the filter and set aside the recently used one in a clean, breathable location to dry for 5-7 days, and cycle through the filters sequentially.



The Filter Media used in the OSR-M1 is made of similar nonwoven polymer materials as is used in a disposable mask, also known as a filtering facepiece respirator (FFR). The same protocols and disclaimers as used for FFR can be applied to the OSR-M1 filter media.

Before inserting a filter into the mask check for any rips, tears, or mechanical failures. If any failures are found discard the filter immediately. Be sure to orient the filter correctly in the mask: green side towards face, and if label is shown, label away from face.

  1. Open the filter adapter by rotating the Filter Grill counterclockwise while holding the Filter Adapter by the grips on the face-side of the mask.
  2. Remove and discard the used filter disc.
  3. (Optionally) Clean the entire mask.
  4. Before inserting a filter into the mask check for any rips, tears, or  mechanical failures. If any failures are found discard the filter immediately.
  5. Remove a new Filter Media disc from its bag and place the filter disc into the Filter Adapter. The white or labeled (if present) side should be face outwards away from the face (green points towards your face).
  6. Ensure the disc is centered and level in the Filter Adapter.
  7. Replace and tighten the Filter Grill by seating against the Filter Adapter and rotating clockwise until you hear 3 or more clicks.


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