1. 30-Day notices, 135-day premarket approval (PMA) supplements and 75-day humanitarian device exemption (HDE) supplements for manufacturing method or process changes: guidance for industry and Food and Drug Administration staff Publication: Silver Spring, MD : Center for Devices and Radiological Health, December 16, 2019 Subject(s): Device Approval -- standardsEquipment and Supplies -- standardsManufactured Materials -- standardsDevice Approval -- legislation & jurisprudenceTime FactorsHumansUnited StatesUnited States. Department of Health and Human Services.United States. Food and Drug Administration.United States.