Is your mask really stopping COVID spread? Stanford scientist explains use of candle test to check

SAN FRANCISCO (KGO) -- The omicron surge has caused the CDC to finally update its mask guidance late last week, indicating a clear preference for the level of protection offered by N95 and KN95 masks.

It's also reopened the conversation about mask efficacy.
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One test that has emerged on social media is the "blow out the candle" test. If you can blow out a candle through your mask, that means too much air is getting through, potentially expelling COVID viral particles to others near you.

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ABC7 News Anchor Kristen Sze performed the experiment Monday using three different masks: N95, surgical and cloth. She was unable to blow out the candle wearing N95 or surgical, but easily blew out the candle in a cloth mask.

Dr. Amy Price, a senior research scientist at Stanford's Anesthesia Informatics and Media Lab, joined Sze on ABC7 News 3 p.m. program "Getting Answers" Monday to discuss the reveals and limits of the candle test.
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Price says the candle test is far from fool proof, but is a simple way to know when a mask is clearly not doing its job. She also talked about simple ways to improve your mask efficacy, including rubbing it with a latex glove for 30 seconds to create an electrical charge as an extra barrier for the virus to get through.

VIDEO: Evidence emerging that cloth masks are not as effective as surgical masks against COVID