Experts say N95 masks can be reused depending on the situation. (Associated Press)

(We Chinese in America Media Editor Tang Zhao, January 12, 2022) To improve resistance to highly contagious strains of the Omicron virus, health experts are recommending that people switch to higher-protection N95, KN95 or KF94 masks during a surge in cases. However, the disadvantage is that it cannot be thrown into the washing machine like a cloth mask. Disposable masks such as N95 are not only used once, but they cannot be reused for a long time. How long will it last? Experts say: It depends. Matt Carlson, chief of safety at UC San Francisco Hospital, said that there is generally no consensus on how many times masks such as N95 can be worn, but decisions should be made based on a number of variables, including mask quality, long-term fit and integrity sex, and the environment in which people wear them.

As the name suggests, N95 and KN95 masks can effectively filter up to 95% of suspended particulates in the air. N95 is a mask that meets U.S. standards and is also recognized by the National Institute for Occupational Safety and Health. KN95 is a mask that meets Chinese standards. KF94 is a mask that meets South Korean standards and can filter up to 94% of suspended particles in the air, which is basically equivalent to South Korea's N95 mask.

When will old masks be phased out?

Experts say that no matter which type of mask is used, the longer it is worn, the looser the elastic band and mask fit, and frequent touching or removal of the mask also increases the chance of compromising the structural integrity of the mask. Carson said that to determine whether a mask can continue to be used, it should be frequently observed for its quality, such as whether the filter layer is visibly wet or stained, or whether the edge of the mask can no longer fit closely to the face. If so, it should be replaced with a new mask. Kirsten Bibbins-Domingo, associate dean of Population Health and Health Equity at UC San Francisco, said that in general, she won't wear an N95 mask more than five times. Dirty or wet, it will be thrown away. Some experts say a mask can be reused for up to a week if handled and stored properly. However, if the mask has been worn in a high-risk setting like a hospital, the safest thing to do is to throw it away.

How to handle and save?

The federal Centers for Disease Control and Prevention (CDC) urges the public not to touch the front of the mask when wearing it, because the virus on the hands may contaminate the mask, and vice versa. When removing the mask, grasp the elastic band to remove it. When removing a mask while eating in a public place, it is best to keep it clean by putting it in your pocket, purse or paper bag, and then cleaning your hands. Also wash your hands again after putting the mask back on. If you want to reuse the mask, the CDC recommends placing the mask in a dry, ventilated bag, such as a paper bag or a mesh cloth bag.

Bibbins-Domingo pointed out that UCSF staff would put masks in paper bags with their names on them, hang them to dry, and then reuse them.

Can masks be sterilized?

At present, there is no way for the public to disinfect masks by themselves. "While there are some technologies that can effectively disinfect disposable masks, they are only available to medical units in crisis situations," Carson said. Therefore, when the mask is no longer suitable for continued use, it should be discarded.

(Source: Compiled from Online Information)