By Sandee LaMotte | CNN
It’s official — wearing a mask not only protects others from your expelled respiratory droplets, it protects you as well, according to new guidance from the US Centers for Disease Control and Prevention.
“The evidence is piling up that masks work in terms of driving down the risk for everyone,” said Harvard environmental health researcher Joseph Gardner Allen, who directs the Healthy Buildings program at the Harvard T.H. Chan School of Public Health.
But what type of mask will offer you and others the best protection from any novel coronavirus circulating in the air?
“You want to have a minimum two-ply mask, preferably a three-ply mask,” said Allen, who has focused his career on “sick buildings” and how they affect worker performance and productivity.
Stay away from bandanas and gaiter masks unless that’s all that’s available. A recent study found both types to be the least effective in terms of protection.
“In addition to level of filtration, we have to pay attention to fit,” Allen continued. “You want the mask to go over the bridge of the nose, below the chin and be flush on the face, resting along the skin. You want your breath going through the filter media and not escaping out the sides.”
No N95 masks or exhalation valves, please
This is important: Do not buy N95 masks for your personal use, the CDC says. While those are the most effective — filtering out 95% of all particles — they are considered critical supplies and must continue to be reserved for health care workers and other medical first responders.
In addition, N95 masks must be fitted to adhere to the unique contours of each doctor or nurse’s face. You and your loved ones don’t have access to that sort of expert fitting.
And be especially wary of the look-alike N95-type masks being sold at major retail distributors, Dr. Marybeth Sexton, an assistant professor of medicine in the division of infectious diseases at Emory University in Atlanta, told CNN recently.
“Some of those community-use N95 masks have exhalation valves in them,” she said. “They do make them more comfortable to wear, but you’re not protecting the people around you — it’s putting your airflow right out in the environment.
“It may actually make things worse because it concentrates your breath into that valve, allowing it to come through with some force and the droplets may travel a little farther. So we strongly recommend that people don’t wear a mask that has an exhalation valve.”
A tightly woven cloth mask
Cloth masks with high thread counts seem to be an excellent choice, according to the new guidance from the CDC.
Look for a tight weave of 100% cotton, according to studies. Use the light test to check the weave: If you can easily see the outline of the individual fibers when you hold up the mask to the light, it’s not likely to be effective.
You want as many layers …read more
Source:: The Mercury News – Entertainment