Section 120.534 - Determination of Dosages of Unsealed Radioactive Material for Medical Use(A) A licensee shall determine and record the activity of each dosage prior to medical use.(B) For a unit dosage, this determination must be made either by direct measurement or by a decay correction, based on the measurement made by a manufacturer or preparer licensed pursuant to 105 CMR 120.128(J) or equivalent provisions of the Nuclear Regulatory Commission, or an Agreement State.(C) For other than unit dosages, this determination must be made by direct measurement of radioactivity or by a combination of measurements of radioactivity and mathematical calculations or combination of volumetric measurements and mathematical calculations, based on the measurement made by a manufacturer or preparer licensed pursuant to 105 CMR 120.128(J) or equivalent provisions of the Nuclear Regulatory Commission, or an Agreement State.(D) Unless otherwise directed by the authorized user, a licensee shall not use a dosage if the dosage differs from the prescribed dosage by more than 20%.(E) A licensee shall retain a record of the dosage determination required by 105 CMR 120.534 in accordance with 105 CMR 120.590(H).Amended by Mass Register Issue 1480, eff. 10/14/2022.