There are a lot of varieties of face masks to choose from according to the level of protection needed and how long protection is required. Some face masks are only intended to catch bacteria that could be shed in liquid droplets and aerosols from the wearer's mouth and nose and must be changed or disposed of within a very short period of time. Other masks are specifically designed to protect the wearer from inhaling tiny, dangerous airborne pollutants and toxic gases and can be used for weeks or even months without requiring any replacement filters.
In any event where one finds themselves exposed to a high risk of getting sick due to airborne contaminants a face mask should be used to protect the respiratory system. This is when it would be helpful to understand which types of face masks are meant for which threats. The biggest reason one would need to wear a mask today is to have protection against the H1N1 (Swine Flu) pandemic that is reaching all over the world.
You might have heard about many different masks intended to protect you from the Swine Flu, including the N95 and N100 masks (recommended by NIOSH), gas masks, or even surgery masks. Each mask is different and not all of them can protect you from viruses like the Swine Flu.
Surgical Masks: These masks are not an appropriate method of protection as they are only intended to reduce the spread of bacteria or viruses if the wearer sneezes or coughs. They are not actually designed to protect the wearer from inhaling the infected particles. It’s possible for surgical masks to block some particles but they are much less effective than respirators, which are designed to block such particles.
Half-Face Cartridge Respirators (Gas Masks): When you are specifically targeting an airborne biological contaminant such as a virus or bacteria that causes flu, you only need to be worried about your nose and mouth. These masks cover a much larger area than your standard half-face respirators, and are usually for chemical warfare or military use where biological weapons are a major threat. These masks are generally much more expensive than any temporary particle mask, and since the areas they’re designed to cover are much more advanced than protection from the swine flu requires, they are not a recommended source of protection to pursue.
N95 and N100 Respirator Masks: The ‘N’ in the name of these masks stands for ‘Not Oil Resistant’, which allows one to be more specific with their needs so they’re not paying for things they don’t need. The number in the name indicates the percentage of airborne particles that particular mask will protect you from. (N95 filters at least 95%, N100 filters at least 99.97%) This type of mask is called an Air-Purifying Escape Respirator (APER) and is intended to be used by the general public for Chemical, Biological, Radiological, and Nuclear incidents. APERs are specifically designed to guard the wearer from inhaling viruses and bacteria that can be spread as tiny particles through the air. They are inexpensive and temporary; most are to be disposed of after one-time use. These masks are also NIOSH certified specifically for use during the Swine Flu pandemic.
Referring to all face masks, the U.S. Centers for Disease Control and Prevention (CDC) said, “If used correctly, face masks and respirators may help reduce the risk of getting influenza, but they should be used along with other preventive measures, such as avoiding close contact and maintaining good hand hygiene.”