{"data":{"id":"us/10-cfr-35.61","jurisdiction":"us","citation":"10 CFR 35.61","heading":"Calibration of survey instruments.","body":"(a) A licensee shall calibrate the survey instruments used to show compliance with this part and 10 CFR Part 20 before first use, annually, and following a repair that affects the calibration. A licensee shall—\n(1) Calibrate all scales with readings up to 10 mSv (1000 mrem) per hour with a radiation source;\n(2) Calibrate two separated readings on each scale or decade that will be used to show compliance; and\n(3) Conspicuously note on the instrument the date of calibration.\n(b) A licensee may not use survey instruments if the difference between the indicated exposure rate and the calculated exposure rate is more than 20 percent.\n(c) A licensee shall retain a record of each survey instrument calibration in accordance with § 35.2061.","path":["Title 10—Energy","CHAPTER I—NUCLEAR REGULATORY COMMISSION","PART 35—MEDICAL USE OF BYPRODUCT MATERIAL","Subpart C—General Technical Requirements"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-10.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:24:09Z","sha256":"18bf43ec4a9b81c9726119074282ce876d7f85f625de69fdb5ae912da403f9dd","source_id":"us-cfr","stale":true,"prev":"us/10-cfr-35.60","next":"us/10-cfr-35.63"},"notice":"GroundRules: Original legal text. Not legal advice."}