Which of the following is an example of an air purifying respirator?

The full face elastomeric respirator is indeed an example of an air-purifying respirator. This type of respirator is designed to filter out harmful substances from the air before they are inhaled. It provides a tight seal around the face, which enhances its effectiveness in filtering out airborne contaminants. The full-face design also offers additional protection for the eyes, making it suitable for environments where hazardous materials may be present.

The other options represent different kinds of respiratory protection. The powered air purifying respirator uses a fan to draw air through filters, while a self-contained breathing apparatus supplies a separate air source. A disposable mask may offer limited filtration but does not fit the definition of a dedicated air-purifying respirator in the same way that the full face elastomeric respirator does.