Which of the following respirators is specifically used for filtering out particulates?

The correct choice, which is air-purifying respirators, is specifically designed to filter out particulates from the inhaled air. These respirators utilize a variety of filtration mechanisms to capture dust, pollen, smoke, and other solid particles, as well as some vapors and gases, depending on the type of filter used.

Air-purifying respirators function by pulling contaminated air through a filter or a combination of filters and then delivering clean air to the wearer. This makes them particularly effective in environments where airborne particulates are present, such as in construction, agriculture, or industries involving dust or chemical exposure.

In contrast, self-contained breathing apparatuses and atmosphere-supplying respirators provide breathable air from an external source or tank rather than filtering ambient air. These types of respirators are used in highly hazardous environments where oxygen levels may be low or toxic substances are present, rather than simply for filtering particulates. Reusable filters can be part of an air-purifying respirator, but by themselves do not constitute a complete respirator system.