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Record QC and radiochemistry results

Some Lab Results carry extra detail beyond the reported value: quality-control statistics for spike and duplicate results, and radiochemistry measurements for radionuclide analyses. Each Lab Result holds at most one quality-control (QC) record and one radiochemistry record, entered on the result's QC and Rad tabs.

Before you start
  • Permission: You need permission to edit the Lab Result's project data.
  • Prerequisites: The Lab Result must exist — see Manage lab data.

Record quality-control detail​

  1. Open the Lab Result and select the QC tab.

  2. Enter the fields that apply:

    FieldWhat to enter
    Original ConcentrationThe unspiked concentration of the source sample
    Spike AmountThe amount added to the spike; must not be negative
    Percent RecoveryThe measured recovery of the spike
    Relative Percent DifferenceThe RPD between a result and its duplicate; must not be negative
    Lower Control LimitThe lower acceptance limit; must not exceed the upper limit
    Upper Control LimitThe upper acceptance limit
    RPD Control LimitThe RPD acceptance limit; must not be negative

  3. Select Save.

To remove the QC record, select Remove QC Data and confirm.

Record radiochemistry detail​

  1. Open the Lab Result and select the Rad tab.

  2. Enter the fields that apply:

    FieldWhat to enter
    Min Detectable ConcentrationThe minimum detectable concentration (MDC)
    Min Detectable ActivityThe minimum detectable activity (MDA)
    Critical LevelThe decision threshold for a detection
    Counting ErrorThe counting uncertainty
    Total Propagated UncertaintyThe total propagated uncertainty
    Uncertainty BasisThe statistical coverage the counting error and total propagated uncertainty were reported at (1S, 2S, 3S, CL95, or CL99). Leave it empty when the lab did not state it — a coverage factor is never assumed.
    Combined Standard UncertaintyThe combined standard uncertainty (1-sigma by definition)
    Tracer RecoveryThe recovery of the radiochemical tracer
    Decay CorrectedWhether the result is corrected for radioactive decay

  3. Select Save.

To remove the radiochemistry record, select Remove Rad Data and confirm.

note

A radiochemistry result value can be negative — a measurement below zero after blank correction is legitimate — so the result's reported value is not floored at zero.