mask myths: no, carbon dioxide won't make you sick

today, dr. theresa tam told canadians that they should use non-medical masks along with social distancing measures.“wearing a non-medical mask is an additional measure that you can take to protect others around you,” canada’s top doctor said in a news conference this afternoon, adding that a mask doesn’t necessarily protect person wearing it.“a non-medical mask can reduce the chance of your respiratory droplets coming into contact with others or landing on surfaces,” tam said. “the science is not certain but we we need to do everything that we can and it seems a sensible thing to do.”until now, tam has not supported the idea of non-healthcare professionals wearing masks.with all the changing information, it’s no surprise that most people either feel they don’t need one, or believe that masks don’t work to prevent the spread of covid-19. they’re also confused about how to correctly wear a mask — and which work best. here are some common misconceptions debunked.myth: masks don’t workafter months of telling canadians that masks don’t work in protecting people from covid-19 – and that no data showing their effectiveness is available — the tide has shifted. a study by researchers from hong kong university and those at the university of maryland found that wearing a mask lowered the rate at which the virus was transmitted through airborne particles or respiratory droplets by 50% and up to 75%. other recent research on hong kong residents also finds that wearing masks significantly prevents spread of the disease. myth: masks allow carbon dioxide to accumulate, and can make you sick.hypercapnia is the medical term for breathing in co2. mild symptoms include dizziness, lightheadedness, fatigue, headache, feeling short of breath and disorientation. a representative from the u.s. centers for disease control and prevention (cdc) recently told reuters: “the co2 will slowly build up in the mask over time. however, the level of co2 likely to build up in the mask is mostly tolerable to people exposed to it.” the takeaway is that because most people are using the masks for at most an hour or two — healthcare workers excepted — they are not going to suffer from hypercapnia. they might get a mild headache. myth: masks don’t need to cover your noseyes, they do. covid-19 attaches to receptors in the nose, which is the gateway to the body. scientists have found that specific cells in the nose have high levels of the proteins that the covid-19 virus uses to get into our cells. failing to wear a mask that covers your nose also doesn’t protect others should you sneeze, releasing droplets into the air and potentially infecting other people. myth: masks are only helpful if i am coughingmany people have covid-19 but don’t have symptoms. so they’re not coughing. but they are talking. and talking releases many smaller respiratory particles into the air, where they can be breathed in by other people. an editorial in the journal aerosol science and technology suggests that these airborne particles can also hang in the air for some time. so, covering your face with a mask can contain these particles and prevent their spread. myth:cloth masks and surgical masks are as good as n95 masksan n95 mask offers more protection than a surgical mask and cloth mask because it can filter out both large particles and 95% of very small particles. surgical masks and cloth masks can prevent a person from breathing in larger droplets but not tiny ones. although the sars-covis virus is tiny, and could pass through a cloth or surgical mask, the good news is that it is often expelled in larger droplets that cloth masks will catch. myth: wearing a mask keeps me safewearing a mask can give you a false sense of security, says joseph blondeau, a clinical microbiologist and head of clinical microbiology at royal university hospital, saskatoon health region. he says that rather than viewing it as the sole way you’re staving off infection, it should be seen as a tool in a larger group of anti-infection measures, such as frequent hand washing, social distancing and sanitization of surfaces. “a mask is not a replacement for all of these measures,” he says. “it is a tool that should be combined with other things.” myth: disposable masks need to be thrown out after one useif you’ve taken a quick run to buy milk wearing a disposable mask, don’t throw it out when you get home. instead, let it sit for 10-14 days and the virus (if it’s present) will die. “the simplest way is to take a mask and let it sit out for two weeks,” said michael mina, an assistant professor of epidemiology at harvard university’s t.h. chan school of public health in a recent article in the journal of engineering. “we know the virus tends to die out after ten days or so.” exceptions to this rule would be workers in high-risk settings who are exposed to large amounts of the virus and have saturated their masks with moisture through all-day wear.don’t miss the latest on covid-19, reopening 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