437-007-0350 Respiratory Protection When Machines Are Operated (1) When the operation of machines expose any employee to dusty conditions and an air-purifying respirator or filtering facepiece is used for personal protection, the respirator must have a N-95 filter rating unless employees are monitored under typical work conditions and found to be exposed to total dust levels less than 10 milligrams per cubic meter of air per 8-hour time-weighted average (TWA). (2) When the use of a respirator is required by the standard, the employer must provide respirators, medical evaluations and training, at no cost to the employee. (3) Before any employee is permitted to use an air-purifying respirator, they must complete a medical evaluation performed by a physician or other licensed health care professional. NOTE 1: This evaluation can be performed by using: (a) A medical questionnaire, or (b) An initial medical examination that obtains the same information as the medical questionnaire. (c) A medical evaluation is not required if the employee is voluntarily using an approved respirator. NOTE 2: Use Appendix 7-G, Respiratory Medical Evaluation Questionnaire (Mandatory). (4) The employer must train employees: (a) About the respiratory hazards to which they are potentially exposed during routine work. (b) In the proper use of respirators, including putting on and removing them, any limitations on their use, maintenance and storage. (5) Respirators must be clean and maintained in good working order. (6) Respirators must be stored in a dry and sanitary place. (7) Respiratory protection must be: (a) NIOSH-certified. (b) Used in compliance with the conditions of its certification. (8) When wearing air purifying respirators for personal protection: (a) Facial hair must not come between the sealing surface on the facepiece and the face. (b) Facial hair must not interfere with valve function. (c) Conditions must not interfere with the face-to-facepiece seal or valve function (facial characteristic, glasses, etc.). (9) A qualitative fit test (QLFT) must be performed before employees use a tight fitting air purifying respirator. NOTE: This is a pass/fail fit test to assess the adequacy of respirator fit that relies on the individual's response to the test agent. (10) Employees using a tight fitting air-purifying respirator must perform a user seal check to ensure that an adequate seal is achieved each time the respirator is put on. (11) Employees must use either the positive and negative pressure check method, or follow the respirator manufacturer's recommended user seal check method. (12) Positive pressure checks must be performed by closing off the exhalation valve and exhale gently into the facepiece. NOTE 1: The face fit is considered to be satisfactory if a slight positive pressure can be built up inside the facepiece without any evidence of outward leakage of air at the seal. NOTE 2: For most respirators this method of leak testing requires the wearer to first remove the exhalation valve cover before closing off the exhalation valve and then carefully replacing it after the test. (13) Negative pressure checks must be performed by closing off the inlet opening of the canister or cartridge(s) by covering with the palm of the hand(s) or by replacing the filter seal(s), and then inhaling gently so that the facepiece collapses slightly. NOTE 1: If the facepiece remains in its slightly collapsed condition and no inward leakage of air is detected, the tightness of the respirator is considered satisfactory. NOTE 2: The design of the inlet opening of some cartridges cannot be effectively covered with the palm of the hand. The test can be performed by covering the inlet opening of the cartridge with a thin latex or nitrile glove. Statutory/Other Authority: ORS 654.025(2) & 656.726(4) Statutes/Other Implemented: ORS 654.001 - 654.295 History: OSHA 5-2003, f. 6-2-03, cert. ef. 12-1-03