What type of respirator should not be used in hazardous gas environments?

In hazardous gas environments, air-purifying respirators are not effective because they rely on filters or cartridges to remove contaminants from the air that the user breathes. These devices can only filter out particles or specific gases if the correct filter is chosen and if the concentration of the hazardous gas is below certain levels. In situations where there are high concentrations of hazardous gases that can be harmful or lethal, relying on an air-purifying respirator can pose a significant risk to the user's safety.

In contrast, other types of respiratory protection equipment, like full face respirators or powered air-purifying respirators, may provide additional features or capabilities, such as a sealed fit or powered air circulation, making them more suitable for environments with hazardous gases. Additionally, dust masks are primarily designed for filtering out particulates and do not provide the necessary protection against gases at all. This emphasizes the importance of selecting the right respiratory protection for the specific hazards present in the environment.