Respirators are designed to help reduce the wearer's respiratory exposure to airborne contaminants such as particles, gases, or vapors. Respirators and filters must be selected based on the hazards present. They come in various sizes and styles, and should be individually selected to fit the wearer's face and to provide a tight seal. A proper seal between the user's face and the respirator forces inhaled air to be pulled through the respirator's filter material, thereby providing protection. A simple design is demonstrated using Catia V5