The CRC®-15R provides a precise, accurate, fast and very convenient method of measuring the activity of a radioisotope sample for Nuclear Medicine and Brachytherapy.

The activity of the sample is displayed with a proper unit when a sample of unknown strength (activity) of a known radioisotope is placed in the ionization chamber and the correct calibration number is selected. The sample must be placed in the same geometry as the reference source used to determine the calibration number by using the appropriate source holder. Activity measurements are performed by the state-of-the-art electronic circuits in conjunction with an ionization chamber possessing extremely high sensitivity and stability. The effects of the sample container, sample volume, and activity concentration are minimized by optimizing the counting geometries. Nine preset nuclide keys are provided for the most often used radioisotopes. Four user assignable nuclide keys are provided for commonly used radioisotopes that do not have a preset nuclide key. Assays may be made reliably in the Chamber, from as low as 1 microcurie (0.1 megabequerel) for most radioisotopes to as high as 8 curies [200 giga (109) Becquerel] of Tc99m. The 6cm diameter and 25cm deep ionization chamber well allows convenient measurements of virtually any radioisotope geometry in clinical use including whole generators, syringes and seed trains. The external shield of the ionization chamber protects users from exposure to intensive radiation and reduces the effect from background radiation on low-level measurements.