Radium-226, measurement Response

The accuracy of any measurement will depend upon the calibration of the instrument used. The calibration of an instrument determines its response to a known amount or concentration of radioactivity. This allows a correlation to be made between the instrument reading and the actual amount or concentration present. A range of activities of radium-226 standard reference materials (SRM) is available from the U.S. Department of Commerce, National Bureau of Standards (NBS) as solutions for calibrating detection systems. Also, an elevated radon atmosphere may be produced in a chamber, and samples drawn and measured in systems previously calibrated by radon emanation from an NBS radium-226 SRM. Other radon detectors may then be filled from or exposed in the chamber and standardized based on this "secondary" standard (NCRP 1988). Analytical methods for measuring radon in environmental samples are given in Table 6-2. These methods provide indirect measurements of radon i.e., the activity emitted from radon and radon progeny is detected and quantitied. 

---