{"data":{"id":"us/42-cfr-493.1265","jurisdiction":"us","citation":"42 CFR 493.1265","heading":"Standard: Virology.","body":"(a) When using cell culture to isolate or identify viruses, the laboratory must simultaneously incubate a cell substrate control or uninoculated cells as a negative control material.\n(b) The laboratory must document all control procedures performed, as specified in this section.","path":["Title 42—Public Health","CHAPTER IV—CENTERS FOR MEDICARE \u0026 MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES","SUBCHAPTER G—STANDARDS AND CERTIFICATION","PART 493—LABORATORY REQUIREMENTS","Subpart K—Quality System for Nonwaived Testing"],"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":"1935530ccfc1c8a7aebbd7c147ebdca64c72945c86cbf9b3e41558b237c16d59","source_id":"us-cfr","stale":true,"prev":"us/42-cfr-493.1264","next":"us/42-cfr-493.1267"},"notice":"GroundRules: Original legal text. Not legal advice."}