N95 mask cleaning ?

[BobbyV]

All these cleaning options are better than NO MASK! 50/50 is better than 0/0 Right?

Depends on what type I guess . . . some provide more protection than others. But that's IF they're worn correctly.

 

[Dale00]

Depends on what type I guess . . . some provide more protection than others. But that's IF they're worn correctly.

No need to use alcohol on an N95 mask: it damages the functionality of the mask.....as was already stated. Reference the article Yukonjack shared
Use 150 degree dry heat for 30 minutes making sure the mask is suspended and not close to metal.....this sounds like a method anyone can do.....many thanks Yukonjack

 

[OKCHunter]

I only skimmed this thread so I apologize if already discussed. What about a microwave oven? I have an old one sitting in my garage.

 

[Dale00]

Based on this (below), it does not look good to use a microwave.....not enough research done to see how much is needed to kill the virus and how much is too much/damaging to the mask either by starting a fire or breaking down the functionality of the special fabric......get a cheap toaster oven maybe

Microwave Generated Steam (MGS):
Plastic reservoirs with perforated tops as shown are filled with about 50 mL of tap water at room temperature, the contaminated N95 mask is placed atop the center of the assembly and loaded into a commercially available microwave oven and exposed to radiation for two minutes (one minute each side of mask). Use of this method resulted in an average log reduction of 5.06 of viable virus. Note that many designs of N95 mask feature metallic nosebands which when exposed to microwave radiation will melt the surrounding area of the mask, rendering it unusable (12). However, average aerosol penetration and airflow resistance was not shown to have changed significantly for masks subjected to this disinfection method that did not contain any metallic components. It is important to note significant potential issues with this approach. As noted, the metal noseband can damage the mask and can also create a fire hazard. Microwaves are available in a variety of wattages both with and without rotating carousels. This study also did not identify whether any of these are important parameters in order to achieve viral inactivation while maintaining filter integrity.

https://consteril.com/covid-19-pandemic-disinfection-and-sterilization-of-face-masks-for-viruses/

 

[BobbyV]

No need to use alcohol on an N95 mask: it damages the functionality of the mask.....as was already stated. Reference the article Yukonjack shared
Use 150 degree dry heat for 30 minutes making sure the mask is suspended and not close to metal.....this sounds like a method anyone can do.....many thanks Yukonjack

I was referring to the type of mask involved . . . not what was used to clean it.

But thanks . . .

 

[SlugSlinger]

This is what the Tulsa fire department is using. Yes, they are cleaning and reusing masks until the fall apart. A primary ingredient is alcohol although it is not the active ingredient. Supplies are starting to run low.


https://www.metrex.com/en-us/products/surface-disinfectants/cavicide

This stuff is being made by a Tulsa firefighter and is very promising.

https://www.hypochlorousacid.com/default.asp

Alcohol should NOT be used in cleaning the N95 masks.


https://utrf.tennessee.edu/informat...tection-sterilization-of-face-mask-materials/

Q2: Can the masks be treated using alcohol?
A: No. Face masks cannot be sterilized using alcohol because the charges will be erased by either alcohol liquid or its vapor, as described above.

My colleague Dr. Cai, a retired filtration testing scientist, collected experimental data in February 2020, shown in the table below, that support my past results.

Table 1. Measured FE after treatment with alcohol and soap/water (Cai et al., Feb. 2020).

Treatment using alcohol or soap water FE
Initial filtration efficiency (3-fold medical mask) 93.2%
After immersion in medical alcohol 67.0%
After treatment with saturated IPA vapor (ISO) 47.4%
After washing by hand with soap/water for 2 minutes 54.0%
The first web link in Q3 shows similar charge decay results after sterilization using alcohol.

 

[SlugSlinger]

This is what the TFD is using now.

 

[dennishoddy]

Use 150 degree dry heat for 30 minutes making sure the mask is suspended and not close to metal

Sounds like those Garden Master jerky machines from walmart might just be the ticket. Totally plastic with stackable trays that could be modified to allow room for the masks. They heat up to 180 degrees