When people have to work with airborne toxic materials, a respirator mask can reduce the exposure and protect the wearer. However, these devices only provide protection if they are properly selected for the hazard to which the wearer is exposed and used correctly. Most workers don’t have the benefit of workplace programs to make sure that their masks fit and function correctly, so this consumer-oriented fact sheet is designed to help ensure that they select the right equipment for their needs and know how to use it safely.
A respirator mask consists of an elastic mask that fits over the head, with a mouthpiece and vent to inhale air, an inlet for the filter cartridge attached to it, and sometimes drinking tubes or corrective lenses for vision. The mask can be adjusted for a comfortable fit. Most models also have a button to activate the filter cartridge and another to deactivate it.
Cartridges or filters are available for many different types of chemical and biological toxins. Most masks can be fitted with multiple filters, and it is possible to find a filter for any type of hazard. However, even the best-designed and most expensive respirator only provides protection if the correct cartridge or filter is chosen for the specific hazard to which the person is exposed.
Once the filters are used up, or have a limited capacity for absorption (charcoal or other substrates can fill up), or if the hazard is much more intense than the mask was designed to handle, protection is lost. The same is true for self-contained breathing apparatus (SCBA) systems that supply their own air from a tank, such as the ones used by firefighters.
Using a respirator can be difficult for some people, such as those with lung diseases or claustrophobia, elderly people, or children. Using one can be especially hard for those with weak or impaired breathing, as it may not be easy to inhale through the mask’s mouthpiece. If the person does not wear the mask tightly enough, it may leak air around its edges, which could lead to an overdose of a hazardous substance or even asphyxiation.
The first masks were made of a chemical-absorbing fabric that fitted over the face, with a circular lens and mouthpiece. These were known as smoke hoods, and they were introduced for military use in 1915. Later, sorbent compounds were added to improve their effectiveness against chlorine and mustard gas.
In the 1960s, powered air-purifying respirators came on the market. These systems blew a stream of clean air through the mask, which made them easier to wear for extended periods. They were often used by laboratory researchers and others working in the field with hazardous chemicals. They are less common now, but are still used by some individuals who need to stay at a job site for long periods. They are also used in some emergency situations, such as when a chemical spill occurs at a plant or airport. gas masks for sale