What device is used in respirators to trap and remove contaminants from the air being breathed by the wearer?

The use of a filter in respirators is crucial for ensuring the air that the wearer inhales is free from harmful contaminants. A filter works by physically trapping particles, including dust, aerosols, and other pollutants, through various mechanisms such as mechanical filtration and electrostatic attraction. The effectiveness of a filter is pivotal in providing respiratory protection, as it allows clean air to enter while preventing the inhalation of dangerous substances.

While a canister can also be a part of certain types of respirators, particularly those designed to remove gases and vapors, and thus can be a valid choice in specific contexts, the question specifically asks for the device that traps and removes contaminants. A respiratory mask generally refers to the overall piece of equipment worn by the user, which may include a filter but is not itself the filtration element. A pesticide scrubber, while a useful device in specific applications, is not relevant to general respiratory protection in the same way a filter is designed to be. Thus, the filter stands out as the primary component responsible for contaminant removal in the context of respirators.