Sample Type

Analysis

Approximate Minimum Detectable Concentration^a

(MDC)

Derived Concentration Guide^b

(DCG)

Air

(particulate filter)^e

Gross alpha^c

1.07 x 10^-15 µCi/mL

2 x 10^-14 µCi/mL

Gross beta^d

1.97 x 10^-15 µCi/mL

3 x 10^-12 µCi/mL

Specific gamma (¹³⁷Cs)

1.61 x 10^-16 µCi/mL

4 x 10^-10 µCi/mL

²³⁸Pu

1.64 x 10^-18 µCi/mL

3 x 10^-14 µCi/mL

^239/240Pu

1.10 x 10^-18 µCi/mL

2 x 10^-14 µCi/mL

²⁴¹Am

2.10 x 10^-18 µCi/mL

2 x 10^-14 µCi/mL

⁹⁰Sr

6.16 x 10^-17 µCi/mL

9 x 10^-12 µCi/mL

Air (charcoal cartridge)^e

¹³¹I

1.70 x 10^-15 µCi/mL

4 x 10^-10 µCi/mL

Air

(atmospheric moisture)^f

³H

1.06 x 10^-13 µCi/mL_water

1 x 10^-7 µCi/mL_air

Air (precipitation)

³H

1.14 x 10^-7 µCi/mL

2 x 10^-3 µCi/mL

³H

Milk

¹³¹I

0.65 pCi/L

--

¹³⁷Cs

2.35 pCi/L

--

Game Animal Tissue^g

¹³⁷Cs

2.68 pCi/kg

--

a      The MDC is an estimate of the concentration of radioactivity in a given sample type that can be identified with a 95% level of confidence and precision of  plus or minus 100% under a specified set of typical laboratory measurement conditions.

b      DCGs, 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.

c      The DCG for gross alpha is equivalent to the DCGs for ^239,240Pu and ²⁴¹Am.

d      The DCG for gross beta is equivalent to the DCGs for ²²⁸Ra

e      The approximate MDC is based on an average filtered air volume (pressure corrected) of 570 m³/week.

f       The approximate MDC is expressed for tritium (as tritiated water) in air, and is based on an average filtered air volume of 39 m³, assuming an average sampling period of eight weeks.

g     The approximate MDC assumes a sample size of 500 g.