This allows you to breathe easily from your nose or mouth which is the biggest advantage of a full face snorkel mask! I tried using my Seaview mask and it works great, now I am swimming laps 3 times week! The other big reason it is worth it to purchase a snorkel flotation vest it will give you total confidence on the water.
Some masks include an exhalation valve to expel the breath outwards, but that current of air is not filtered.
A comparative study in the Hong Kong Special Administrative Region reported a statistically significant lower cumulative incidence of covid-19 associated with mask wearing than in selected countries where mask wearing was not mandatory.
Many speculative manufacturers have been forced to quit due to changing export rules and tighter licensing requirements in China and weaker demand for lower quality products globally.
Centers for Disease Control and Prevention.
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