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CFR > 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 (parts 80 to 87) > PART 84—APPROVAL OF RESPIRATORY PROTECTIVE DEVICES > SUBPART I—Gas Masks (§84.110 to §84.126) > 84.112—Canisters and cartridges in parallel; resistance requirements.
84.112—Canisters and cartridges in parallel; resistance requirements.
Where two or more canisters or cartridges are used in parallel, their resistance to airflow shall be essentially equal.