PAPR (powered air-purifying respirator) systems include the components needed to filter ambient air and provide workers with safe, breathable air. PAPR systems have a battery-powered blower that passes ambient air through a filter into the facepiece. Filters and cartridges are chosen to protect against specific particulates, vapors, and gases in the environment. Hoods and other loose-fitting systems do not require fit testing, while tight-fitting facepieces do.