Validation of a procedure for the analysis of Ra in naturally occurring radioactive materials using a liquid scintillation counter.

An analytical procedure for detecting Ra in naturally occurring radioactive materials (NORMs) using a liquid scintillation counter (LSC) was developed and validated with reference materials (zircon matrix, bauxite matrix, coal fly ash, and phosphogypsum) that represent typical NORMs. The Ra was released from samples by a fusion method and was separated using sulfate-coprecipitation. Next, a Rn-emanation technique was applied for the determination of Ra.