EPA Method 903

Summit Environmental Technologies prides itself in its expansive testing capabilities in a variety of different fields. To find out if Summit conducts this test, contact us at 330-253-8211 today.

PDF IconView Actual EPA Method 903 (PDF File)

EPA Method 903:
Alpha-Emitting Radium Isotopes in Drinking Water . Official Name: EPA Method 903.0, Alpha-Emitting Radium Isotopes in Drinking Water

The radium in the drinking water sample is collected by co-precipitation with barium and lead sulfate, and purified by re-precipitation from EDTA solution. Citric acid is added to the drinking water sample to assure that complete interchange occurs before the first precipitation step. The final BaSO4 precipitate, which includes radium-226, radium-224, and radium-223 is alpha counted to determine the total disintegration rate of the radium isotopes.

This method covers the measurement of the total soluble alpha emitting radioisotopes of radium, namely radium-223, radium-224 and radium-226 in drinking water. Part 141 of the Interim Primary Drinking Water Regulations, Federal Register, July 9, 1976, has promulgated the maximum contaminant levels of radium-226 plus radium-228 not to exceed 5 pCi/L.

EPA Method Guidance CD-ROM (includes MCAWW Methods, and most current EPA Methods)

Natural barium present in the sample, ingrown alpha emitting isotopes.

QC Requirements:
The counting efficiency for radium alpha particles with barium sulfate carrier present must be determined using a standard (known) radium alpha activity and 32mg of barium carrier as BaSO4.

Maximum Holding Time:
See Section 3 - Method 900



None specified.

Sample Prep:
None provided.

Precision and accuracy data for this method was taken from an intercomparison study of eleven laboratories using this method. Of the 40 tests performed, 29 tests (87 aliquots analyzed) gave acceptable results (results within 3 sigma of the known value, with 1 sigma equal to 15% of the known value). The extent of acceptability in the 40 tests (29 acceptable) was 72.5%.

1 pCi/L

Revision Number:
Version 2.0, June 1999.