A gas mask is a device that protects the wearer from toxic airborne materials. It consists of a tight-fitting facepiece that contains filters and an exhalation valve held by straps. It can be worn alone or in conjunction with a protective hood. The filters, which can be replaced, clean the air but do not add oxygen (some masks are connected by hose to a tank of oxygen).
There are many different types of gas masks and the best one for you depends on the specific threats you might encounter. You will also have to decide whether you want the mask to be capable of protecting against both particulates and gases. There are basic, disposable models that are designed to filter out only particulates (like smoke and combusted debris from a fire) and more complex options that can be fitted with various types of gas absorbers (like charcoal or activated carbon) for protection against chemical weapons like chlorine, sulfur dioxide, and mustard gas.
The most basic models filter out only particulates with a screen that is about 1 micron thick—for comparison, an average human hair is 75 microns in width. Gases are more challenging because they can easily slip through screens and other particle-filtering systems. Many gas masks are rated with the letter N or P to indicate how effective they are at filtering out particles and gases, respectively. N95 masks, for example, are rated to filter out 95% of particles that are 0.3 microns in size or larger; these include pepper spray and other abrasive chemicals that can clog standard filters. Other ratings are available to identify different types of protection, including NBC and CBRN masks that protect against chemical, biological, radiological, and nuclear threats for an eight hour period.
If you choose to go with a non-military, disposable model it is important to look at the rubber material and thickness, lens material and thickness, canister type, airflow design, and the fit. The most durable and comfortable models are typically made of bromobutyl rubber, which is resistant to blister agent chemical weapons. Some models have a small reservoir built into the frame of the mask for liquids, which can be filled with water or a solution to help counteract the effects of dry rot or contamination.
Depending on the type of mask you choose, the filters and absorbers can be purchased separately or in kits with a tin canister that holds the absorbents via a hose. While some manufacturers offer disposable filters and cartridges, they are not as reliable or easy to use as the more robust military-issue options.
Some DIY hacks for getting a good seal on a mask are available—like applying petroleum jelly to your nose or mouth—but they do not provide the same level of protection that a real mask will. You will have to invest in a quality mask that offers a high value for the money and test it out for durability and effectiveness. This will ensure that it will stand up to real-world conditions and be ready to use in the event of an emergency. gas masks