Respirator
Respirators are devices that are used either to aid in breathing or to protect the wearer from dust and/or harmful fumes. The first type is known as an air-supplied respirator; an example of this would be a scuba diver's equipment or an oxygen mask used in hospitals. The second type is an air-purifying respirator; this type forces air through a filtering element of some kind.
Call us at (888) 360-4215 to speak with a mesothelioma paralegal
The concept of the air-purifying respirator actually dates back to the early 1500s. Inventor Leonardo Da Vinci had designed an early chemical weapon in the form of a powder; he suggested that
military personnel could protect themselves by wearing dampened, finely-woven cloth over their noses and throats.
The first practical air-supplied respirators date from around 1800; these generally consisted of a rubberized cloth bag worn over the head with openings for the eyes and a some type of conduit through which the wearer could breathe gas from a tank.
The first air purifying respirator was patented in 1848. Known as "Haslett's Lung Protector," this was a simple face mask with a moistened wool or cotton filter. The invention was improved and in common industrial use within the next 35 years. During the late 19th century, chemists in Scotland and England were experimenting with charcoal and lime, resulting in the first respirators able to filter out toxic gases using activated charcoal filters.
Today's respirators may be half face or full face. Most are "negative pressure" respirators in which the wearer must breathe in unassisted. There are also positive pressure respirators, which are power-assisted.
The most effective type of respirator employs what is called a HEPA filter. This is an acronym for "High Efficiency Particulate Air." Such filters have been shown to remove no less than 99.97% of airborne particles down to a diameter of three-tenths of a micrometer (too small to be seen with the unaided eye).