Respiratory protection equipment filters out harmful particulates, gases, vapors and fumes. It can be disposable or reusable. Disposable respirators are for one use only and are used in medical, sanding and grinding applications. They include surgical masks and dust face masks. Reusable respirators use large filters or cartridges to filter out harmful gases, fumes and particulates. They come in a half facepiece form that covers the nose and mouth and a full facepiece form that covers the entire face. PAPR (powered air purifying respirators) and SAR (supplied air respirators) also purify a worker's breathing air. They filter air and send it through a breathing tube into the worker's enclosed headgear. This allows the worker to perform tasks in a hazardous environment.