CFR›Title 10›Chapter I›Part 50›Subject Group Classification and Description of Licenses ContainsSections 50.20–50.23CorpusDaily eCFRDisplayed edition2026-04-15Last updated2026-04-15 Sections 50.20 § 50.20 Two classes of licenses. 50.21 § 50.21 Class 104 licenses; for medical therapy and research and development facilities. 50.22 § 50.22 Class 103 licenses; for commercial and industrial facilities. 50.23 § 50.23 Construction permits. Previous Backfitting Backfitting Next Enforcement Enforcement