Researchers at UCLA have found that the most commonly used N95 mask decontamination processes do a good job quickly and inexpensively without damaging them.

Pandemic-related shortages of the masks, designed to filter out 95% of airborne particulates, have led healthcare providers to seek effective decontamination methods that would not damage the masks.

The UCLA researchers reviewed 42 laboratory studies of five decontamination processes. They found that ultraviolet germicidal irradiation, moist heat and microwave-generated steam processing effectively removed pathogens, preserved respirator filtration, and had short treatment times using readily available equipment. They concluded that vaporized hydrogen peroxide is a good alternative, although the process takes longer and is more expensive than the others. They found ethylene oxide (EtO) decontamination may leave toxic residues and is less easily implemented.

Ultraviolet irradiation and vaporized hydrogen peroxide appeared to cause the least damage to the N95s, designed for single-use. The researchers recommended more research on decontamination effectiveness for SARS-CoV-2 because few studies specifically examined this pathogen.

Their study was published in the Journal of the American Medical Association.