Face masks provide protection against transmission of respiratory viruses. Additional steps to help the spread of respiratory viruses include hand washing, 呼吸礼仪, 当你生病的时候避开其他人.

Lisa Maragakis, m.s.D., M.P.H., an expert in infection prevention, answers questions about face masks.

口罩有哪些不同类型?

疾控中心提供了一个概述 各类口罩和呼吸器. 在一般情况下, the most important things you can do are to choose a mask that fits well, and wear it consistently and properly when it is recommended or in situations that you are required to do so.

布口罩

在非卫生保健环境中, multiple-layer fabric cloth masks are excellent barriers for containing respiratory droplets if they are worn consistently and properly, 遮住口鼻.

手术及外科口罩

These are loose-fitting masks designed to cover the mouth and nose. Medical grade surgical or procedural masks provide excellent protection due to their filtration and fluid resistance. 一个简单的 “打结和折叠”技术 can be used to improve the fit of rectangular surgical or procedural masks.

n95和其他呼吸器

N95防护口罩 offer a higher level of filtration than cloth, surgical or procedural masks. However, they are not necessary to protect people from viruses under normal circumstances. 为了达到最佳效果, 呼吸器必须经过测试并正确佩戴, 紧贴人的脸的.

N95防护口罩, Dräger respirators and powered air purifying respirators (PAPRs) are used by medical professionals caring for patients with viral infections such as COVID-19, 当执行高风险或产生气溶胶的程序时.

面盾牌

A face shield is a piece of rigid, transparent plastic attached to a headband. 塑料片覆盖面部，延伸到下巴以下.

Dentists and dental hygienists sometimes wear them when working close to patients’ mouths. 医生, 护士和技术人员可能会使用面罩, 还有口罩, when performing procedures that could propel blood or other substances into the air.

You should not wear a face shield in place of a mask or wear clear shield-like face masks, which are different than face shields and have gaps around the face and therefore do not provide the same protection as wearing a mask.

大多数人在公共场合不需要面罩.

What about neck gaiters, bandanas and masks with exhalation valves?

None of these three types of face coverings works as well as a proper face mask. 好的面膜有双层可洗性, breathable fabric that helps keep the wearer from spreading potentially infected droplets into the air. A bandanna tied around the face does not work as well as a mask because it is open at the bottom. 绑腿(一管薄的), stretchy knit fabric that can be worn around the neck and pulled up to cover the nose and mouth) is usually too thin to provide adequate protection. 同样的, masks with exhalation valves can allow droplets to escape into the air.

约翰霍普金斯医学院不允许戴头巾, 推荐十大正规网赌平台佩戴带呼吸阀的绑腿或口罩, 工作人员或访客在我们的地点.

如何正确佩戴口罩?

每次戴口罩时，请确保:

• You clean your hands with soap or hand sanitizer before putting the mask on or taking it off.
• 这是一贯和适当的穿着. 面罩:为了呼吸或说话而经常拉下的面罩, 或者是戴在鼻子下面, 没有效果.
• The mask conforms to your face without gaps — it is important that most of the air you breathe in and out flows through the mask rather than around the mask through gaps at the sides, 顶部还是底部.
• Your cloth mask is made from several layers of tightly woven fabric and fits well over your nose and mouth to be an effective filter.
• The mask has a flexible nose bridge to conform to the face and prevent fogging of eyeglasses.
• 说话和移动时，它保持在原地, so it can be worn without slipping and so it does not require you to touch it frequently.
• The mask is comfortable enough to wear without adjusting it for the time you need to keep it on.

了解更多关于 如何正确佩戴口罩.

我怎样洗我的布面膜?

• Masks made of fabric, such as cotton, can be washed in your regular laundry using hot water.
• 一次性, blue surgical masks cannot be laundered or cleaned and should be thrown away when they are visibly soiled or damaged.
• After laundering your fabric masks, tumble dry them in the dryer on a high setting.
• You might consider using a nonscented laundry detergent if you are sensitive to perfumes, 所以戴口罩更容易.
• 你也可以用热肥皂水手洗口罩. Scrub the mask for at least 20 seconds and dry it on high heat in the dryer.
• 不使用口罩时，请将干净的口罩存放在干净的地方.

我应该多久清洗一次面膜或面罩?

每次戴完口罩都要清洗干净. 这降低了传播冠状病毒或其他细菌的风险.

我需要多少个口罩?

最好至少有两个. 这样，如果你的口罩在洗，你就会有一个新鲜的口罩.

口罩和COVID-19

如果我目前患有COVID-19，我需要戴口罩吗?

是的. If you are actively infected with the coronavirus and cannot stay completely away from others in your home, 你鼻子或嘴巴里的飞沫可能会感染其他人. Stay away from others as much as possible and wear your mask around others until your doctor says it’s safe to discontinue wearing it.

Do I need to wear a mask if I am fully vaccinated and have received a booster?

Although being fully vaccinated and/or boosted reduces your chance of catching or spreading the coronavirus, 它并没有完全消除它. 如果你感染了冠状病毒而不知道, a mask keeps your respiratory droplets and particles from infecting others. Check the mask recommendations in your area to help decide whether you need to mask.

Do I need to wear a mask if I am around someone who is at greater risk for getting COVID-19?

保护他人不感染COVID-19非常重要. 即使你已经完全接种了疫苗并注射了加强剂, 戴口罩提供了额外的一层保护, especially when you are around a person who may be at greater risk of COVID-19. 同样的, people who are at greater risk should strongly consider wearing a mask to help protect themselves.