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Appendix B

Table B-1. Summary of Approximate Minimum Detectable Concentrations for Radiological Analyses Performed during First Quarter 2019

Sample Type


Approximate Minimum Detectable Concentrationa

Derived Concentration Standardb

(particulate filter)e

Gross alphac

5.1 x 10-16 µCi/mL

3.4 x 10-14 µCi/mL

Gross betad

1.4 x 10-15 µCi/mL

2.5 x 10-11 µCi/mL


8.4 x 10-17 µCi/mL

9.8 x 10-11 µCi/mL


3.4 x 10-17 µCi/mL

2.5 x 10-11 µCi/mL


5.0 x 10-18 µCi/mL

4.1 x 10-14 µCi/mL


7.9 x 10-18 µCi/mL

3.7 x 10-14 µCi/mL


7.2 x 10-18 µCi/mL

3.4 x 10-14 µCi/mL

Air (charcoal cartridge)e


7.3 x 10-16 µCi/mL

2.3 x 10-19 µCi/mL

Air (atmospheric moisture)e


90.9 pCi/Lwater

3.3 x 10-13 µCi/mLair

1.9 x 106 pCi/Lwater

102.1 x 10-7 µCi/mLair

Air (precipitation)


92.0 pCi/L

1.9 x 106 pCi/Lwater



0.5 pCi/L

1.3 x 103 pCi/Lf


1.0 pCi/L

3.0 x 103 pCi/Lf

  1. The MDC is an estimate of the concentration of radioactivity in a given sample type that can be identified with a 95 percent level of confidence. MDCs are calculated and reported by the laboratories based on actual ESER sample results following analysis.
  2. DCSs, set by the DOE, represent reference values for radiation exposure. They are based on a radiation dose of 100 mrem/yr for exposure through a particular exposure mode such as direct exposure, inhalation, or ingestion of water.
  3. Based on the most restrictive human-made alpha emitter (239Pu).

  4. Based on the most restrictive human-made beta emitter (90Sr).

  5. The approximate MDC is based on an average filtered air volume (pressure corrected) of 445 m3/week.
  6. There is no DCS established for radionuclides in milk. However, The DCS shown is for the radionuclide ingested in water.


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