thank you machan very valuable info
The bottom line is what I wrote before.... That's backed by research studies by several health entities & Universities. Don't rely on fancy claims not based on scientific facts.
"By contrast, masks decontaminated with UV and VHP could be used up to three times and function properly. Masks decontaminated with dry heat could be used two times before function declined.
Results indicate that N95 respirators can be decontaminated and re-used in times of shortage for up to three times for UV and HPV, and up to two times for dry heat. "
In extreme circumstances you can recycle masks. But it's not recommended or very effective. The mask will look good because you cannot notice a difference. Simply because a difference is not visible, you cannot assume it's ok.
Particle capture of the filter depends mainly on two factors - Mechanical & Electrostatic. When you apply chemicals the electrostatic properties diminish drastically.
The CDC recommends the following simple method. It's
Mask Rotation.
Buy a set number of at least 5 Nos of N95 masks, and rotate their use each day, allowing them to dry for long enough that the virus is no longer viable (> 72 hours). Proper storage for this technique requires either hanging the respirators to dry, or keeping them in a clean, breathable container like a paper bag between uses. Make sure the masks do not touch each other.
Also the CDC
does NOT approve the following methods...
Bleach, Alcohol, Baking, Boiling, Ethylene oxide, Microwave, Sanitizing wipes, Soapy Water.
Currently research is underway to find a suitable method of using Liquid Hydrogen Peroxide & Steam.
Also there are industrial sterilization methods that can reuse a N95 mask upto 10 times. (Steris)
In summary, There is no definitive "best practice"for N95 re-use and re-processing. These methods are options for times of crisis and should not be used routinely if mask supply is sufficient.
But I should add - a mask will always give you a certain degree of protection from air-borne droplet transmission. So wearing even a reused mask is better than not wearing one at all.