is a device designed to protect the wearer from inhaling particulate
matter, including airborne microorganisms, fumes, vapours and gases.
There are two main categories: the air-purifying respirator which forces
contaminated air through a filtering element, and the air-supplied
respirator in which an alternate supply of fresh air is delivered.
Within each category, different techniques are employed to reduce or
eliminate noxious airborne contaminants.
range from relatively inexpensive single-use, disposable face masks to
more robust reusable models with replaceable cartridges.
They are also sometimes referred to as a dust mask or a gas mask.