Dust Masks and Respirator Masks
There are two classes of breathing protection available, depending on the type and severity of the pollutant that needs to be protected against. These types of protection are respirators and dust masks. Dust masks are generally composed of cloth, are lightweight, and are disposable. Dust masks are held in place over the nose and mouth, using elastic and nose pads. A dust mask is rated based on the types of particles that the mask will protect against. A typical dust mask for painters and carpenters will protect against dust: sawdust, concrete, soil, flour, drywall, fiberglass, and silica. This type of mask provides no protection against oils, volatile gases or microscopic contaminants. A dust mask of the class N95 provides protection against microscopic contaminants, such as the virus that causes the common cold and the SARS virus. N95 dust masks are expensive, while a typical painter's mask is cheap. For protection against gases or solvents, a respirator is needed.
Respirators come in two forms: air-purifying and air-supply respirators. An air-purifying respiratory mask utilizes one or more filter cartridges to filter the incoming air. All air is routed through the cartridges. Cartridges are available to protect against a wide range of pollutants: aerosols, solvents, adhesives, organic vapors, lead, asbestos, cadmium, arsenic, ketones. A simple filter cartridge may contain active charcoal. More complicated filters are needed to filter out more reactive chemicals. Unlike dust masks, a respirator is typically reusable. While the respirator is reusable, the cartridges have a limited lifespan that starts once they are first used. The other type of respiratory mask, the air-supply respirator, is used in situations where the ambient air cannot be purified enough to be breathed, or in situations where there is no air available. An air-supply respirator utilizes tanks of pressurized air to provide an independent, safe air supply. An advantage of the air-supply respirator is that it does not depend on the ambient air and no filtration is required. A disadvantage of the air-supply respirator is its dependence on air tanks. Once the supply of air is exhausted, the tanks must be refilled by a qualified air supplier.
Respirators come in two forms: air-purifying and air-supply respirators. An air-purifying respiratory mask utilizes one or more filter cartridges to filter the incoming air. All air is routed through the cartridges. Cartridges are available to protect against a wide range of pollutants: aerosols, solvents, adhesives, organic vapors, lead, asbestos, cadmium, arsenic, ketones. A simple filter cartridge may contain active charcoal. More complicated filters are needed to filter out more reactive chemicals. Unlike dust masks, a respirator is typically reusable. While the respirator is reusable, the cartridges have a limited lifespan that starts once they are first used. The other type of respiratory mask, the air-supply respirator, is used in situations where the ambient air cannot be purified enough to be breathed, or in situations where there is no air available. An air-supply respirator utilizes tanks of pressurized air to provide an independent, safe air supply. An advantage of the air-supply respirator is that it does not depend on the ambient air and no filtration is required. A disadvantage of the air-supply respirator is its dependence on air tanks. Once the supply of air is exhausted, the tanks must be refilled by a qualified air supplier.
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