US Patent 6854464 Respiration protecting apparatus

A respiratory protection apparatus has a face body, and a right side and a left side of a vertical centerline of the body are respectively provided with filtering devices each of which houses an electrical fan unit therein. Without narrowing the field of the front vision, without increasing the front side weight, and without deteriorating the work efficiency and comfortable fitting, the apparatus ensures the air flow rate of more than 120 liters per minute. Moreover, the electrical fan unit may be detachable from the face body, so that the face body is easily washed and parts are readily replaced with new ones.