{"data":{"id":"us/42-cfr-84.122","jurisdiction":"us","citation":"42 CFR 84.122","heading":"Breathing resistance test; minimum requirements.","body":"(a) Resistance to airflow will be measured in the facepiece or mouthpiece of a gas mask mounted on a breathing machine both before and after each test conducted in accordance with §§ 84.124, 84.125, and 84.126, with air flowing at a continuous rate of 85 liters per minute.\n(b) The maximum allowable resistance requirements for gas masks are as follows:\nMaximum Resistance\n[mm. water-column height]\nType of gas mask Inhalation Exhalation\nInitial Final 1\nFront-mounted or back-mounted (without particulate filter) 60 75 20\nFront-mounted or back-mounted (with approved particulate filter) 70 85 20\nChin-style (without particulate filter) 40 55 20\nChin-style (with approved particulate filter) 65 80 20\nEscape (without particulate filter) 60 75 20\nEscape (with approved particulate filter) 70 85 20\n1 Measured at end of the service life specified in Tables 5, 6, and 7 of this subpart.","path":["Title 42—Public Health","CHAPTER I—PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES","SUBCHAPTER G—OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES","PART 84—APPROVAL OF RESPIRATORY PROTECTIVE DEVICES","Subpart I—Gas Masks"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-42.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:11Z","sha256":"8aa6ef58440a2e364395e8dafe30e5d6ee1986087ee0df2dec1de7a2ae5a9c82","source_id":"us-cfr","stale":true,"prev":"us/42-cfr-84.121","next":"us/42-cfr-84.123"},"notice":"GroundRules: Original legal text. Not legal advice."}