Total Alpha Emitting Radium with Filters
Oral Presentation
Prepared by T. Patten
Inter-Mountain Labs, 1673 Terra Avenue, Sheridan, WY, 82801, United States
Contact Information: [email protected]; 307-672-8945
ABSTRACT
A limited validation study was performed for a "method deviation" to ASTM D2460 (Test Method for Alpha-Particle-Emitting Isotopes of Radium in Water). The method ASTM D2460 is synonymous with the procedures of Standard Method 7500 Ra-B and EPA 903. Three commercial labs received two spiked drinking water samples and analyzed them in triplicate with the deviation and without the deviation. The change or deviation to ASTM D2460 was in the preparation of the barium precipitate that is presented for alpha counting on a gas proportional counter. The traditional method is to centrifuge and transfer the barium precipitate to a planchette with water, then evaporate the water prior to alpha counting on a gas proportional counter. The deviation simply filters the barium precipitate onto a filter that is appropriate for drying and then alpha counting on a gas proportional counter. The study found that the results are comparable and not statistically different. The study was undertaken because the deviation is more efficient and can be done with less labor. Results indicated that the modified procedure produced some additional benefits. The use of filters improves recoveries of barium precipitate and the geometry improves the count efficiency as well. These two improvements combined allow for improved, 5%-20%, detection capability.
Oral Presentation
Prepared by T. Patten
Inter-Mountain Labs, 1673 Terra Avenue, Sheridan, WY, 82801, United States
Contact Information: [email protected]; 307-672-8945
ABSTRACT
A limited validation study was performed for a "method deviation" to ASTM D2460 (Test Method for Alpha-Particle-Emitting Isotopes of Radium in Water). The method ASTM D2460 is synonymous with the procedures of Standard Method 7500 Ra-B and EPA 903. Three commercial labs received two spiked drinking water samples and analyzed them in triplicate with the deviation and without the deviation. The change or deviation to ASTM D2460 was in the preparation of the barium precipitate that is presented for alpha counting on a gas proportional counter. The traditional method is to centrifuge and transfer the barium precipitate to a planchette with water, then evaporate the water prior to alpha counting on a gas proportional counter. The deviation simply filters the barium precipitate onto a filter that is appropriate for drying and then alpha counting on a gas proportional counter. The study found that the results are comparable and not statistically different. The study was undertaken because the deviation is more efficient and can be done with less labor. Results indicated that the modified procedure produced some additional benefits. The use of filters improves recoveries of barium precipitate and the geometry improves the count efficiency as well. These two improvements combined allow for improved, 5%-20%, detection capability.
