With the current shortage of face masks, the most common question is if you can clean and reuse the kn95 face mask.
Unfortunately, the kn95 mask is not supposed to be reused. It is recommended that they are replaced at all times.
However, because of the limited supply, the CDC has recommended the limited reuse and extended use of N95 masks.
Extended Use and Reuse
However, given the current circumstances and the shortage, medical professionals are looking for a way to reuse.
The CDC has given recommendations on the reuse and extended use of the N95 face masks. For extended use, it has recommended that the N95 should be discarded if they are used during procedures generating aerosols if they are contaminated with blood, nasal secretions or patient’s bodily fluids. They should also be discarded if there had been close contact with or exit from the care area of an infected patient.
The CDC also recommends washing hands with soap and water or hand sanitizer before and after adjusting or touching the mask.
In addition to the above, the CDC recommends the following for reuse. The used mask should be hung in a given storage area or kept in a clean breathable container which should be cleaned regularly or disposed of. The masks should not touch each other when stored and the user should be clearly identified.
No touching the inside of the mask. In case it happens then discard it and clean your hands.
Use gloves when wearing the mask and doing a seal check and then discard them.
Only the same wearer can reuse or extend the use of a mask to prevent the spread of infection.
Decontaminating the kn95 Masks
On decontaminating the masks, CDC has no peer-reviewed information.
However, what is available are key principles for cleaning face masks from the Society of American Gastrointestinal and Endoscopic Surgeons. Note that these have not been endorsed by the CDC or the manufactures of the masks.
i.The cleaning method must be sufficient to inactivate the mask’s viral load.
ii.Preserve filtration capacity and iconic charge as much as possible.
iii.The mask’s fit cannot be compromised.
iv.Mask can’t be soiled by makeup or body fluids.
Some of the decontamination methods recommended include:
i.Vaporized hydrogen peroxide
Duke Health researchers successfully sterilized N95 face masks using vaporized hydrogen peroxide. However, they used specialized equipment in their laboratory. The hydrogen peroxide infiltrated the layers of the masks and killed the microbes but the mask did not deteriorate.
Unfortunately, only a few hospitals have the technology to do this.
The masks can be decontaminated using heat. This was shown by the University of Tennessee study in which a number of tests using heat were performed and it was suggested that a mask can be heated at 70c for 30 minutes. This decontaminates the mask and preserves the integrity of the filter.
iii.Using UV-C Light
Some hospitals are using UVGI (Ultraviolet Germicidal Irradiation) to decontaminate the masks and kill the coronavirus. A non-peer reviewed study indicated that UV-C light can inactivate the coronavirus. The study was conducted by penetrating adequate light on the surface of the mask with specific dosing measurements.
The method requires the entire mask and straps to be dosed with UV-C.
Remember, the CDC has not recommended the decontamination of the kn95 face masks.
No. You cannot wash the kn95 facemask
You should not wash the mask in soapy water or spray/wet with liquid alcohol.
If the outer and inner layer of the kn95 masks is made of paper, then it should not be boiled, washed or steamed. This can cause the filer medium material to disintegrate.
Also, cleaning with soapy water or alcohol reduces the filtration efficiency of the mask. However, if the outer and inner layers are not made of paper, then you may boil it. Dr. Tsai of UT Knoxville suggests submerging the kn95 mask in 125C boiling water for 3 minutes and don’t stir excessively.