What should not be expected from the use of air-purifying respirators?

The correct response highlights that air-purifying respirators are not designed to completely eliminate all airborne contaminants. Instead, these respiratory protection devices work by filtering out specific pollutants or hazardous particles from the air, thereby reducing the concentration of harmful substances that a person might inhale.

While air-purifying respirators can effectively lower the inhalation risks associated with certain contaminants, they do not offer a guarantee of total air purity. For instance, if the contaminant levels in the air are exceedingly high or the respirator is not suited for the specific hazard present, it may not adequately protect the user. Therefore, it's critical to recognize the limitations of these devices in achieving complete removal of all airborne contaminants, which underscores the necessity for careful selection and usage based on environmental conditions and potential exposure levels.

The other options reflect the benefits of air-purifying respirators, such as providing a reduction in inhalation risks, enhancing work safety, and delivering basic respiratory protection, all of which align with their intended function. However, it's essential to be aware of their limitations regarding comprehensive air purification.